^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * This file is part of UBIFS.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2006-2008 Nokia Corporation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Authors: Artem Bityutskiy (Битюцкий Артём)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * Adrian Hunter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * This file implements VFS file and inode operations for regular files, device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * nodes and symlinks as well as address space operations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) * UBIFS uses 2 page flags: @PG_private and @PG_checked. @PG_private is set if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * the page is dirty and is used for optimization purposes - dirty pages are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * not budgeted so the flag shows that 'ubifs_write_end()' should not release
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * the budget for this page. The @PG_checked flag is set if full budgeting is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * required for the page e.g., when it corresponds to a file hole or it is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * beyond the file size. The budgeting is done in 'ubifs_write_begin()', because
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * it is OK to fail in this function, and the budget is released in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * 'ubifs_write_end()'. So the @PG_private and @PG_checked flags carry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * information about how the page was budgeted, to make it possible to release
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * the budget properly.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * A thing to keep in mind: inode @i_mutex is locked in most VFS operations we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) * implement. However, this is not true for 'ubifs_writepage()', which may be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * called with @i_mutex unlocked. For example, when flusher thread is doing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * background write-back, it calls 'ubifs_writepage()' with unlocked @i_mutex.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * At "normal" work-paths the @i_mutex is locked in 'ubifs_writepage()', e.g.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * in the "sys_write -> alloc_pages -> direct reclaim path". So, in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * 'ubifs_writepage()' we are only guaranteed that the page is locked.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * Similarly, @i_mutex is not always locked in 'ubifs_readpage()', e.g., the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) * read-ahead path does not lock it ("sys_read -> generic_file_aio_read ->
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) * ondemand_readahead -> readpage"). In case of readahead, @I_SYNC flag is not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * set as well. However, UBIFS disables readahead.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) #include "ubifs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) #include <linux/mount.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) #include <linux/migrate.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) static int read_block(struct inode *inode, void *addr, unsigned int block,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) struct ubifs_data_node *dn)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) int err, len, out_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) union ubifs_key key;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) unsigned int dlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) data_key_init(c, &key, inode->i_ino, block);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) err = ubifs_tnc_lookup(c, &key, dn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) if (err == -ENOENT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) /* Not found, so it must be a hole */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) memset(addr, 0, UBIFS_BLOCK_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) ubifs_assert(c, le64_to_cpu(dn->ch.sqnum) >
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) ubifs_inode(inode)->creat_sqnum);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) len = le32_to_cpu(dn->size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) if (len <= 0 || len > UBIFS_BLOCK_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) goto dump;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) if (IS_ENCRYPTED(inode)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) err = ubifs_decrypt(inode, dn, &dlen, block);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) goto dump;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) out_len = UBIFS_BLOCK_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) err = ubifs_decompress(c, &dn->data, dlen, addr, &out_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) le16_to_cpu(dn->compr_type));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) if (err || len != out_len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) goto dump;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) * Data length can be less than a full block, even for blocks that are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) * not the last in the file (e.g., as a result of making a hole and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) * appending data). Ensure that the remainder is zeroed out.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) if (len < UBIFS_BLOCK_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) dump:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) ubifs_err(c, "bad data node (block %u, inode %lu)",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) block, inode->i_ino);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) ubifs_dump_node(c, dn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) static int do_readpage(struct page *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) void *addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) int err = 0, i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) unsigned int block, beyond;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) struct ubifs_data_node *dn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) loff_t i_size = i_size_read(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) dbg_gen("ino %lu, pg %lu, i_size %lld, flags %#lx",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) inode->i_ino, page->index, i_size, page->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) ubifs_assert(c, !PageChecked(page));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) ubifs_assert(c, !PagePrivate(page));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) addr = kmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) if (block >= beyond) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) /* Reading beyond inode */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) SetPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) memset(addr, 0, PAGE_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) if (!dn) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) err = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) i = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) if (block >= beyond) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) /* Reading beyond inode */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) err = -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) memset(addr, 0, UBIFS_BLOCK_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) ret = read_block(inode, addr, block, dn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) err = ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) if (err != -ENOENT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) } else if (block + 1 == beyond) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) int dlen = le32_to_cpu(dn->size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) int ilen = i_size & (UBIFS_BLOCK_SIZE - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) if (ilen && ilen < dlen)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) memset(addr + ilen, 0, dlen - ilen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) if (++i >= UBIFS_BLOCKS_PER_PAGE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) block += 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) addr += UBIFS_BLOCK_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) if (err == -ENOENT) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) /* Not found, so it must be a hole */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) SetPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) dbg_gen("hole");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) goto out_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) ubifs_err(c, "cannot read page %lu of inode %lu, error %d",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) page->index, inode->i_ino, err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) out_free:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) kfree(dn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) SetPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) ClearPageError(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) flush_dcache_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) kunmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) kfree(dn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) ClearPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) SetPageError(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) flush_dcache_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) kunmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) * release_new_page_budget - release budget of a new page.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) * This is a helper function which releases budget corresponding to the budget
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) * of one new page of data.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) static void release_new_page_budget(struct ubifs_info *c)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) struct ubifs_budget_req req = { .recalculate = 1, .new_page = 1 };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) * release_existing_page_budget - release budget of an existing page.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) * This is a helper function which releases budget corresponding to the budget
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) * of changing one one page of data which already exists on the flash media.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) static void release_existing_page_budget(struct ubifs_info *c)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) struct ubifs_budget_req req = { .dd_growth = c->bi.page_budget};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) static int write_begin_slow(struct address_space *mapping,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) loff_t pos, unsigned len, struct page **pagep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) unsigned flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) struct inode *inode = mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) pgoff_t index = pos >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) struct ubifs_budget_req req = { .new_page = 1 };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) int err, appending = !!(pos + len > inode->i_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) struct page *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) dbg_gen("ino %lu, pos %llu, len %u, i_size %lld",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) inode->i_ino, pos, len, inode->i_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) * At the slow path we have to budget before locking the page, because
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) * budgeting may force write-back, which would wait on locked pages and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) * deadlock if we had the page locked. At this point we do not know
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) * anything about the page, so assume that this is a new page which is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) * written to a hole. This corresponds to largest budget. Later the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) * budget will be amended if this is not true.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (appending)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) /* We are appending data, budget for inode change */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) req.dirtied_ino = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) err = ubifs_budget_space(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) if (unlikely(err))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) page = grab_cache_page_write_begin(mapping, index, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) if (unlikely(!page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) if (!PageUptodate(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) if (!(pos & ~PAGE_MASK) && len == PAGE_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) SetPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) err = do_readpage(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) SetPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) ClearPageError(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) if (PagePrivate(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) * The page is dirty, which means it was budgeted twice:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) * o first time the budget was allocated by the task which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) * made the page dirty and set the PG_private flag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) * o and then we budgeted for it for the second time at the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) * very beginning of this function.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) * So what we have to do is to release the page budget we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) * allocated.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) release_new_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) else if (!PageChecked(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) * We are changing a page which already exists on the media.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) * This means that changing the page does not make the amount
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) * of indexing information larger, and this part of the budget
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) * which we have already acquired may be released.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) ubifs_convert_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) if (appending) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) * 'ubifs_write_end()' is optimized from the fast-path part of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) * 'ubifs_write_begin()' and expects the @ui_mutex to be locked
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) * if data is appended.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) if (ui->dirty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) * The inode is dirty already, so we may free the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) * budget we allocated.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) ubifs_release_dirty_inode_budget(c, ui);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) *pagep = page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) * allocate_budget - allocate budget for 'ubifs_write_begin()'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) * @page: page to allocate budget for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) * @ui: UBIFS inode object the page belongs to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) * @appending: non-zero if the page is appended
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) * This is a helper function for 'ubifs_write_begin()' which allocates budget
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) * for the operation. The budget is allocated differently depending on whether
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) * this is appending, whether the page is dirty or not, and so on. This
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) * function leaves the @ui->ui_mutex locked in case of appending. Returns zero
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) * in case of success and %-ENOSPC in case of failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) static int allocate_budget(struct ubifs_info *c, struct page *page,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) struct ubifs_inode *ui, int appending)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) struct ubifs_budget_req req = { .fast = 1 };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) if (PagePrivate(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) if (!appending)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) * The page is dirty and we are not appending, which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) * means no budget is needed at all.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) if (ui->dirty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) * The page is dirty and we are appending, so the inode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) * has to be marked as dirty. However, it is already
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) * dirty, so we do not need any budget. We may return,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) * but @ui->ui_mutex hast to be left locked because we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) * should prevent write-back from flushing the inode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) * and freeing the budget. The lock will be released in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) * 'ubifs_write_end()'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) * The page is dirty, we are appending, the inode is clean, so
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) * we need to budget the inode change.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) req.dirtied_ino = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) if (PageChecked(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) * The page corresponds to a hole and does not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) * exist on the media. So changing it makes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) * make the amount of indexing information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) * larger, and we have to budget for a new
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) * page.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) req.new_page = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) * Not a hole, the change will not add any new
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) * indexing information, budget for page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) * change.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) req.dirtied_page = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) if (appending) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) if (!ui->dirty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) * The inode is clean but we will have to mark
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) * it as dirty because we are appending. This
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) * needs a budget.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) req.dirtied_ino = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) return ubifs_budget_space(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) * This function is called when a page of data is going to be written. Since
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) * the page of data will not necessarily go to the flash straight away, UBIFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) * has to reserve space on the media for it, which is done by means of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) * budgeting.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) * This is the hot-path of the file-system and we are trying to optimize it as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) * much as possible. For this reasons it is split on 2 parts - slow and fast.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) * There many budgeting cases:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) * o a new page is appended - we have to budget for a new page and for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) * changing the inode; however, if the inode is already dirty, there is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) * no need to budget for it;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) * o an existing clean page is changed - we have budget for it; if the page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) * does not exist on the media (a hole), we have to budget for a new
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) * page; otherwise, we may budget for changing an existing page; the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) * difference between these cases is that changing an existing page does
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) * not introduce anything new to the FS indexing information, so it does
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) * not grow, and smaller budget is acquired in this case;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) * o an existing dirty page is changed - no need to budget at all, because
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) * the page budget has been acquired by earlier, when the page has been
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) * marked dirty.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) * UBIFS budgeting sub-system may force write-back if it thinks there is no
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) * space to reserve. This imposes some locking restrictions and makes it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) * impossible to take into account the above cases, and makes it impossible to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) * optimize budgeting.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) * The solution for this is that the fast path of 'ubifs_write_begin()' assumes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) * there is a plenty of flash space and the budget will be acquired quickly,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) * without forcing write-back. The slow path does not make this assumption.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) static int ubifs_write_begin(struct file *file, struct address_space *mapping,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) loff_t pos, unsigned len, unsigned flags,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) struct page **pagep, void **fsdata)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) struct inode *inode = mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) pgoff_t index = pos >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) int err, appending = !!(pos + len > inode->i_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) int skipped_read = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) struct page *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) ubifs_assert(c, ubifs_inode(inode)->ui_size == inode->i_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) ubifs_assert(c, !c->ro_media && !c->ro_mount);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) if (unlikely(c->ro_error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) return -EROFS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) /* Try out the fast-path part first */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) page = grab_cache_page_write_begin(mapping, index, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) if (unlikely(!page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) if (!PageUptodate(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) /* The page is not loaded from the flash */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) if (!(pos & ~PAGE_MASK) && len == PAGE_SIZE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) * We change whole page so no need to load it. But we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) * do not know whether this page exists on the media or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) * not, so we assume the latter because it requires
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) * larger budget. The assumption is that it is better
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) * to budget a bit more than to read the page from the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) * media. Thus, we are setting the @PG_checked flag
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) * here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) SetPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) skipped_read = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) err = do_readpage(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) SetPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) ClearPageError(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) err = allocate_budget(c, page, ui, appending);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) if (unlikely(err)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) ubifs_assert(c, err == -ENOSPC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) * If we skipped reading the page because we were going to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) * write all of it, then it is not up to date.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) if (skipped_read) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) ClearPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) ClearPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) * Budgeting failed which means it would have to force
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) * write-back but didn't, because we set the @fast flag in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) * request. Write-back cannot be done now, while we have the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) * page locked, because it would deadlock. Unlock and free
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) * everything and fall-back to slow-path.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) if (appending) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) ubifs_assert(c, mutex_is_locked(&ui->ui_mutex));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) return write_begin_slow(mapping, pos, len, pagep, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) * Whee, we acquired budgeting quickly - without involving
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) * garbage-collection, committing or forcing write-back. We return
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) * with @ui->ui_mutex locked if we are appending pages, and unlocked
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) * otherwise. This is an optimization (slightly hacky though).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) *pagep = page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) * cancel_budget - cancel budget.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) * @page: page to cancel budget for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) * @ui: UBIFS inode object the page belongs to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) * @appending: non-zero if the page is appended
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) * This is a helper function for a page write operation. It unlocks the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) * @ui->ui_mutex in case of appending.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) static void cancel_budget(struct ubifs_info *c, struct page *page,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) struct ubifs_inode *ui, int appending)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) if (appending) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) if (!ui->dirty)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) ubifs_release_dirty_inode_budget(c, ui);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) if (!PagePrivate(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) if (PageChecked(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) release_new_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) release_existing_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) static int ubifs_write_end(struct file *file, struct address_space *mapping,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) loff_t pos, unsigned len, unsigned copied,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) struct page *page, void *fsdata)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) struct inode *inode = mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) loff_t end_pos = pos + len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) int appending = !!(end_pos > inode->i_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) dbg_gen("ino %lu, pos %llu, pg %lu, len %u, copied %d, i_size %lld",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) inode->i_ino, pos, page->index, len, copied, inode->i_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) if (unlikely(copied < len && len == PAGE_SIZE)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) * VFS copied less data to the page that it intended and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) * declared in its '->write_begin()' call via the @len
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) * argument. If the page was not up-to-date, and @len was
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) * @PAGE_SIZE, the 'ubifs_write_begin()' function did
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) * not load it from the media (for optimization reasons). This
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) * means that part of the page contains garbage. So read the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) * page now.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) dbg_gen("copied %d instead of %d, read page and repeat",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) copied, len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) cancel_budget(c, page, ui, appending);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) ClearPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) * Return 0 to force VFS to repeat the whole operation, or the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) * error code if 'do_readpage()' fails.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) copied = do_readpage(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) if (!PagePrivate(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) attach_page_private(page, (void *)1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) atomic_long_inc(&c->dirty_pg_cnt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) __set_page_dirty_nobuffers(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) if (appending) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) i_size_write(inode, end_pos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) ui->ui_size = end_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) * Note, we do not set @I_DIRTY_PAGES (which means that the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) * inode has dirty pages), this has been done in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) * '__set_page_dirty_nobuffers()'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) ubifs_assert(c, mutex_is_locked(&ui->ui_mutex));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) return copied;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) * populate_page - copy data nodes into a page for bulk-read.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) * @page: page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) * @bu: bulk-read information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) * @n: next zbranch slot
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) * This function returns %0 on success and a negative error code on failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) static int populate_page(struct ubifs_info *c, struct page *page,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) struct bu_info *bu, int *n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) int i = 0, nn = *n, offs = bu->zbranch[0].offs, hole = 0, read = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) loff_t i_size = i_size_read(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) unsigned int page_block;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) void *addr, *zaddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) pgoff_t end_index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) dbg_gen("ino %lu, pg %lu, i_size %lld, flags %#lx",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) inode->i_ino, page->index, i_size, page->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) addr = zaddr = kmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) end_index = (i_size - 1) >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) if (!i_size || page->index > end_index) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) hole = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) memset(addr, 0, PAGE_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) goto out_hole;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) page_block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) int err, len, out_len, dlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) if (nn >= bu->cnt) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) hole = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) memset(addr, 0, UBIFS_BLOCK_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) } else if (key_block(c, &bu->zbranch[nn].key) == page_block) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) struct ubifs_data_node *dn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) dn = bu->buf + (bu->zbranch[nn].offs - offs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640) ubifs_assert(c, le64_to_cpu(dn->ch.sqnum) >
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) ubifs_inode(inode)->creat_sqnum);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) len = le32_to_cpu(dn->size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) if (len <= 0 || len > UBIFS_BLOCK_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) goto out_err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) out_len = UBIFS_BLOCK_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) if (IS_ENCRYPTED(inode)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) err = ubifs_decrypt(inode, dn, &dlen, page_block);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) goto out_err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) err = ubifs_decompress(c, &dn->data, dlen, addr, &out_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) le16_to_cpu(dn->compr_type));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) if (err || len != out_len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) goto out_err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) if (len < UBIFS_BLOCK_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) nn += 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) read = (i << UBIFS_BLOCK_SHIFT) + len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) } else if (key_block(c, &bu->zbranch[nn].key) < page_block) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) nn += 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) hole = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) memset(addr, 0, UBIFS_BLOCK_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) if (++i >= UBIFS_BLOCKS_PER_PAGE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) addr += UBIFS_BLOCK_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) page_block += 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) if (end_index == page->index) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) int len = i_size & (PAGE_SIZE - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) if (len && len < read)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) memset(zaddr + len, 0, read - len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) out_hole:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) if (hole) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) SetPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) dbg_gen("hole");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) SetPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) ClearPageError(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) flush_dcache_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) kunmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) *n = nn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) out_err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) ClearPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) SetPageError(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) flush_dcache_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703) kunmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) ubifs_err(c, "bad data node (block %u, inode %lu)",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) page_block, inode->i_ino);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) * ubifs_do_bulk_read - do bulk-read.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) * @bu: bulk-read information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) * @page1: first page to read
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) * This function returns %1 if the bulk-read is done, otherwise %0 is returned.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) static int ubifs_do_bulk_read(struct ubifs_info *c, struct bu_info *bu,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) struct page *page1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) pgoff_t offset = page1->index, end_index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) struct address_space *mapping = page1->mapping;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) struct inode *inode = mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) int err, page_idx, page_cnt, ret = 0, n = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) int allocate = bu->buf ? 0 : 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) loff_t isize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) gfp_t ra_gfp_mask = readahead_gfp_mask(mapping) & ~__GFP_FS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) err = ubifs_tnc_get_bu_keys(c, bu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) goto out_warn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) if (bu->eof) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) /* Turn off bulk-read at the end of the file */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) ui->read_in_a_row = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) ui->bulk_read = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) page_cnt = bu->blk_cnt >> UBIFS_BLOCKS_PER_PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) if (!page_cnt) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) * This happens when there are multiple blocks per page and the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) * blocks for the first page we are looking for, are not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) * together. If all the pages were like this, bulk-read would
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) * reduce performance, so we turn it off for a while.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) goto out_bu_off;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) if (bu->cnt) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) if (allocate) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) * Allocate bulk-read buffer depending on how many data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) * nodes we are going to read.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) bu->buf_len = bu->zbranch[bu->cnt - 1].offs +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) bu->zbranch[bu->cnt - 1].len -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758) bu->zbranch[0].offs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) ubifs_assert(c, bu->buf_len > 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) ubifs_assert(c, bu->buf_len <= c->leb_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) bu->buf = kmalloc(bu->buf_len, GFP_NOFS | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) if (!bu->buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) goto out_bu_off;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) err = ubifs_tnc_bulk_read(c, bu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) goto out_warn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) err = populate_page(c, page1, bu, &n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) goto out_warn;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) unlock_page(page1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) ret = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) isize = i_size_read(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) if (isize == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) goto out_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) end_index = ((isize - 1) >> PAGE_SHIFT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) for (page_idx = 1; page_idx < page_cnt; page_idx++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) pgoff_t page_offset = offset + page_idx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785) struct page *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) if (page_offset > end_index)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) page = pagecache_get_page(mapping, page_offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) FGP_LOCK|FGP_ACCESSED|FGP_CREAT|FGP_NOWAIT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) ra_gfp_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) if (!page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) if (!PageUptodate(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) err = populate_page(c, page, bu, &n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) ui->last_page_read = offset + page_idx - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) out_free:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) if (allocate)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) kfree(bu->buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) out_warn:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) ubifs_warn(c, "ignoring error %d and skipping bulk-read", err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) goto out_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) out_bu_off:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) ui->read_in_a_row = ui->bulk_read = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815) goto out_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) * ubifs_bulk_read - determine whether to bulk-read and, if so, do it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) * @page: page from which to start bulk-read.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822) * Some flash media are capable of reading sequentially at faster rates. UBIFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) * bulk-read facility is designed to take advantage of that, by reading in one
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) * go consecutive data nodes that are also located consecutively in the same
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) * LEB. This function returns %1 if a bulk-read is done and %0 otherwise.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) static int ubifs_bulk_read(struct page *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) pgoff_t index = page->index, last_page_read = ui->last_page_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) struct bu_info *bu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) int err = 0, allocated = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) ui->last_page_read = index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) if (!c->bulk_read)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841) * Bulk-read is protected by @ui->ui_mutex, but it is an optimization,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842) * so don't bother if we cannot lock the mutex.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844) if (!mutex_trylock(&ui->ui_mutex))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) if (index != last_page_read + 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) /* Turn off bulk-read if we stop reading sequentially */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849) ui->read_in_a_row = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850) if (ui->bulk_read)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851) ui->bulk_read = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855) if (!ui->bulk_read) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856) ui->read_in_a_row += 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) if (ui->read_in_a_row < 3)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859) /* Three reads in a row, so switch on bulk-read */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) ui->bulk_read = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 862)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 863) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 864) * If possible, try to use pre-allocated bulk-read information, which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) * is protected by @c->bu_mutex.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) if (mutex_trylock(&c->bu_mutex))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868) bu = &c->bu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870) bu = kmalloc(sizeof(struct bu_info), GFP_NOFS | __GFP_NOWARN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) if (!bu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) bu->buf = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) allocated = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) bu->buf_len = c->max_bu_buf_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879) data_key_init(c, &bu->key, inode->i_ino,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880) page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) err = ubifs_do_bulk_read(c, bu, page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) if (!allocated)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884) mutex_unlock(&c->bu_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886) kfree(bu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) static int ubifs_readpage(struct file *file, struct page *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) if (ubifs_bulk_read(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897) do_readpage(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 900) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 901)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 902) static int do_writepage(struct page *page, int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904) int err = 0, i, blen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905) unsigned int block;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906) void *addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907) union ubifs_key key;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) #ifdef UBIFS_DEBUG
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913) spin_lock(&ui->ui_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914) ubifs_assert(c, page->index <= ui->synced_i_size >> PAGE_SHIFT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915) spin_unlock(&ui->ui_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) /* Update radix tree tags */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919) set_page_writeback(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) addr = kmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) i = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) while (len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925) blen = min_t(int, len, UBIFS_BLOCK_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) data_key_init(c, &key, inode->i_ino, block);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927) err = ubifs_jnl_write_data(c, inode, &key, addr, blen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930) if (++i >= UBIFS_BLOCKS_PER_PAGE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932) block += 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933) addr += blen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) len -= blen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937) SetPageError(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) ubifs_err(c, "cannot write page %lu of inode %lu, error %d",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) page->index, inode->i_ino, err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940) ubifs_ro_mode(c, err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943) ubifs_assert(c, PagePrivate(page));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944) if (PageChecked(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945) release_new_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947) release_existing_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) atomic_long_dec(&c->dirty_pg_cnt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950) detach_page_private(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951) ClearPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953) kunmap(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955) end_page_writeback(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960) * When writing-back dirty inodes, VFS first writes-back pages belonging to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961) * inode, then the inode itself. For UBIFS this may cause a problem. Consider a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962) * situation when a we have an inode with size 0, then a megabyte of data is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963) * appended to the inode, then write-back starts and flushes some amount of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) * dirty pages, the journal becomes full, commit happens and finishes, and then
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965) * an unclean reboot happens. When the file system is mounted next time, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) * inode size would still be 0, but there would be many pages which are beyond
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967) * the inode size, they would be indexed and consume flash space. Because the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968) * journal has been committed, the replay would not be able to detect this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) * situation and correct the inode size. This means UBIFS would have to scan
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970) * whole index and correct all inode sizes, which is long an unacceptable.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972) * To prevent situations like this, UBIFS writes pages back only if they are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) * within the last synchronized inode size, i.e. the size which has been
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974) * written to the flash media last time. Otherwise, UBIFS forces inode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 975) * write-back, thus making sure the on-flash inode contains current inode size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 976) * and then keeps writing pages back.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 977) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 978) * Some locking issues explanation. 'ubifs_writepage()' first is called with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 979) * the page locked, and it locks @ui_mutex. However, write-back does take inode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 980) * @i_mutex, which means other VFS operations may be run on this inode at the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 981) * same time. And the problematic one is truncation to smaller size, from where
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 982) * we have to call 'truncate_setsize()', which first changes @inode->i_size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 983) * then drops the truncated pages. And while dropping the pages, it takes the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 984) * page lock. This means that 'do_truncation()' cannot call 'truncate_setsize()'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 985) * with @ui_mutex locked, because it would deadlock with 'ubifs_writepage()'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 986) * This means that @inode->i_size is changed while @ui_mutex is unlocked.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 987) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 988) * XXX(truncate): with the new truncate sequence this is not true anymore,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 989) * and the calls to truncate_setsize can be move around freely. They should
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 990) * be moved to the very end of the truncate sequence.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 991) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 992) * But in 'ubifs_writepage()' we have to guarantee that we do not write beyond
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 993) * inode size. How do we do this if @inode->i_size may became smaller while we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 994) * are in the middle of 'ubifs_writepage()'? The UBIFS solution is the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 995) * @ui->ui_isize "shadow" field which UBIFS uses instead of @inode->i_size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 996) * internally and updates it under @ui_mutex.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 997) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 998) * Q: why we do not worry that if we race with truncation, we may end up with a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 999) * situation when the inode is truncated while we are in the middle of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1000) * 'do_writepage()', so we do write beyond inode size?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1001) * A: If we are in the middle of 'do_writepage()', truncation would be locked
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1002) * on the page lock and it would not write the truncated inode node to the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1003) * journal before we have finished.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1004) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1005) static int ubifs_writepage(struct page *page, struct writeback_control *wbc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1006) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1007) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1008) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1009) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1010) loff_t i_size = i_size_read(inode), synced_i_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1011) pgoff_t end_index = i_size >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1012) int err, len = i_size & (PAGE_SIZE - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1013) void *kaddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1014)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1015) dbg_gen("ino %lu, pg %lu, pg flags %#lx",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1016) inode->i_ino, page->index, page->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1017) ubifs_assert(c, PagePrivate(page));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1018)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1019) /* Is the page fully outside @i_size? (truncate in progress) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1020) if (page->index > end_index || (page->index == end_index && !len)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1021) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1022) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1023) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1024)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1025) spin_lock(&ui->ui_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1026) synced_i_size = ui->synced_i_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1027) spin_unlock(&ui->ui_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1028)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1029) /* Is the page fully inside @i_size? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1030) if (page->index < end_index) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1031) if (page->index >= synced_i_size >> PAGE_SHIFT) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1032) err = inode->i_sb->s_op->write_inode(inode, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1033) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1034) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1035) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1036) * The inode has been written, but the write-buffer has
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1037) * not been synchronized, so in case of an unclean
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1038) * reboot we may end up with some pages beyond inode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1039) * size, but they would be in the journal (because
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1040) * commit flushes write buffers) and recovery would deal
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1041) * with this.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1042) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1043) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1044) return do_writepage(page, PAGE_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1045) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1046)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1047) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1048) * The page straddles @i_size. It must be zeroed out on each and every
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1049) * writepage invocation because it may be mmapped. "A file is mapped
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1050) * in multiples of the page size. For a file that is not a multiple of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1051) * the page size, the remaining memory is zeroed when mapped, and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1052) * writes to that region are not written out to the file."
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1053) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1054) kaddr = kmap_atomic(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1055) memset(kaddr + len, 0, PAGE_SIZE - len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1056) flush_dcache_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1057) kunmap_atomic(kaddr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1058)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1059) if (i_size > synced_i_size) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1060) err = inode->i_sb->s_op->write_inode(inode, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1061) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1062) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1063) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1064)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1065) return do_writepage(page, len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1066)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1067) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1068) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1069) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1070) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1071)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1072) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1073) * do_attr_changes - change inode attributes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1074) * @inode: inode to change attributes for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1075) * @attr: describes attributes to change
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1076) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1077) static void do_attr_changes(struct inode *inode, const struct iattr *attr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1078) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1079) if (attr->ia_valid & ATTR_UID)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1080) inode->i_uid = attr->ia_uid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1081) if (attr->ia_valid & ATTR_GID)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1082) inode->i_gid = attr->ia_gid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1083) if (attr->ia_valid & ATTR_ATIME)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1084) inode->i_atime = attr->ia_atime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1085) if (attr->ia_valid & ATTR_MTIME)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1086) inode->i_mtime = attr->ia_mtime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1087) if (attr->ia_valid & ATTR_CTIME)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1088) inode->i_ctime = attr->ia_ctime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1089) if (attr->ia_valid & ATTR_MODE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1090) umode_t mode = attr->ia_mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1091)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1092) if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1093) mode &= ~S_ISGID;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1094) inode->i_mode = mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1095) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1096) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1097)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1098) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1099) * do_truncation - truncate an inode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1100) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1101) * @inode: inode to truncate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1102) * @attr: inode attribute changes description
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1103) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1104) * This function implements VFS '->setattr()' call when the inode is truncated
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1105) * to a smaller size. Returns zero in case of success and a negative error code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1106) * in case of failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1107) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1108) static int do_truncation(struct ubifs_info *c, struct inode *inode,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1109) const struct iattr *attr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1110) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1111) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1112) struct ubifs_budget_req req;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1113) loff_t old_size = inode->i_size, new_size = attr->ia_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1114) int offset = new_size & (UBIFS_BLOCK_SIZE - 1), budgeted = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1115) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1117) dbg_gen("ino %lu, size %lld -> %lld", inode->i_ino, old_size, new_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1118) memset(&req, 0, sizeof(struct ubifs_budget_req));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1120) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1121) * If this is truncation to a smaller size, and we do not truncate on a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1122) * block boundary, budget for changing one data block, because the last
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1123) * block will be re-written.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1124) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1125) if (new_size & (UBIFS_BLOCK_SIZE - 1))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1126) req.dirtied_page = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1128) req.dirtied_ino = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1129) /* A funny way to budget for truncation node */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1130) req.dirtied_ino_d = UBIFS_TRUN_NODE_SZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1131) err = ubifs_budget_space(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1132) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1133) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1134) * Treat truncations to zero as deletion and always allow them,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1135) * just like we do for '->unlink()'.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1136) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1137) if (new_size || err != -ENOSPC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1138) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1139) budgeted = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1140) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1142) truncate_setsize(inode, new_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1144) if (offset) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1145) pgoff_t index = new_size >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1146) struct page *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1148) page = find_lock_page(inode->i_mapping, index);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1149) if (page) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1150) if (PageDirty(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1151) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1152) * 'ubifs_jnl_truncate()' will try to truncate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1153) * the last data node, but it contains
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1154) * out-of-date data because the page is dirty.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1155) * Write the page now, so that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1156) * 'ubifs_jnl_truncate()' will see an already
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1157) * truncated (and up to date) data node.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1158) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1159) ubifs_assert(c, PagePrivate(page));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1161) clear_page_dirty_for_io(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1162) if (UBIFS_BLOCKS_PER_PAGE_SHIFT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1163) offset = new_size &
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1164) (PAGE_SIZE - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1165) err = do_writepage(page, offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1166) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1167) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1168) goto out_budg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1169) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1170) * We could now tell 'ubifs_jnl_truncate()' not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1171) * to read the last block.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1172) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1173) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1174) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1175) * We could 'kmap()' the page and pass the data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1176) * to 'ubifs_jnl_truncate()' to save it from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1177) * having to read it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1178) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1179) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1180) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1181) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1182) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1183) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1184)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1185) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1186) ui->ui_size = inode->i_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1187) /* Truncation changes inode [mc]time */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1188) inode->i_mtime = inode->i_ctime = current_time(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1189) /* Other attributes may be changed at the same time as well */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1190) do_attr_changes(inode, attr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1191) err = ubifs_jnl_truncate(c, inode, old_size, new_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1192) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1193)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1194) out_budg:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1195) if (budgeted)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1196) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1197) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1198) c->bi.nospace = c->bi.nospace_rp = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1199) smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1200) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1201) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1202) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1203)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1204) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1205) * do_setattr - change inode attributes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1206) * @c: UBIFS file-system description object
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1207) * @inode: inode to change attributes for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1208) * @attr: inode attribute changes description
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1209) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1210) * This function implements VFS '->setattr()' call for all cases except
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1211) * truncations to smaller size. Returns zero in case of success and a negative
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1212) * error code in case of failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1213) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1214) static int do_setattr(struct ubifs_info *c, struct inode *inode,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1215) const struct iattr *attr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1216) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1217) int err, release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1218) loff_t new_size = attr->ia_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1219) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1220) struct ubifs_budget_req req = { .dirtied_ino = 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1221) .dirtied_ino_d = ALIGN(ui->data_len, 8) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1222)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1223) err = ubifs_budget_space(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1224) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1225) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1227) if (attr->ia_valid & ATTR_SIZE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1228) dbg_gen("size %lld -> %lld", inode->i_size, new_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1229) truncate_setsize(inode, new_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1230) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1231)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1232) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1233) if (attr->ia_valid & ATTR_SIZE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1234) /* Truncation changes inode [mc]time */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1235) inode->i_mtime = inode->i_ctime = current_time(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1236) /* 'truncate_setsize()' changed @i_size, update @ui_size */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1237) ui->ui_size = inode->i_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1238) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1239)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1240) do_attr_changes(inode, attr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1241)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1242) release = ui->dirty;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1243) if (attr->ia_valid & ATTR_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1244) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1245) * Inode length changed, so we have to make sure
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1246) * @I_DIRTY_DATASYNC is set.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1247) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1248) __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1249) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1250) mark_inode_dirty_sync(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1251) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1252)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1253) if (release)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1254) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1255) if (IS_SYNC(inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1256) err = inode->i_sb->s_op->write_inode(inode, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1257) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1258) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1260) int ubifs_setattr(struct dentry *dentry, struct iattr *attr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1261) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1262) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1263) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1264) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1266) dbg_gen("ino %lu, mode %#x, ia_valid %#x",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1267) inode->i_ino, inode->i_mode, attr->ia_valid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1268) err = setattr_prepare(dentry, attr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1269) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1270) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1271)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1272) err = dbg_check_synced_i_size(c, inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1273) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1274) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1275)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1276) err = fscrypt_prepare_setattr(dentry, attr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1277) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1278) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1279)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1280) if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size < inode->i_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1281) /* Truncation to a smaller size */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1282) err = do_truncation(c, inode, attr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1283) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1284) err = do_setattr(c, inode, attr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1285)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1286) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1287) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1288)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1289) static void ubifs_invalidatepage(struct page *page, unsigned int offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1290) unsigned int length)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1291) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1292) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1293) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1294)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1295) ubifs_assert(c, PagePrivate(page));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1296) if (offset || length < PAGE_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1297) /* Partial page remains dirty */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1298) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1299)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1300) if (PageChecked(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1301) release_new_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1302) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1303) release_existing_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1304)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1305) atomic_long_dec(&c->dirty_pg_cnt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1306) detach_page_private(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1307) ClearPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1308) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1309)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1310) int ubifs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1311) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1312) struct inode *inode = file->f_mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1313) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1314) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1315)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1316) dbg_gen("syncing inode %lu", inode->i_ino);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1317)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1318) if (c->ro_mount)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1319) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1320) * For some really strange reasons VFS does not filter out
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1321) * 'fsync()' for R/O mounted file-systems as per 2.6.39.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1322) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1323) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1324)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1325) err = file_write_and_wait_range(file, start, end);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1326) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1327) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1328) inode_lock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1329)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1330) /* Synchronize the inode unless this is a 'datasync()' call. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1331) if (!datasync || (inode->i_state & I_DIRTY_DATASYNC)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1332) err = inode->i_sb->s_op->write_inode(inode, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1333) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1334) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1335) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1336)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1337) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1338) * Nodes related to this inode may still sit in a write-buffer. Flush
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1339) * them.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1340) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1341) err = ubifs_sync_wbufs_by_inode(c, inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1342) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1343) inode_unlock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1344) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1345) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1346)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1347) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1348) * mctime_update_needed - check if mtime or ctime update is needed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1349) * @inode: the inode to do the check for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1350) * @now: current time
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1351) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1352) * This helper function checks if the inode mtime/ctime should be updated or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1353) * not. If current values of the time-stamps are within the UBIFS inode time
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1354) * granularity, they are not updated. This is an optimization.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1355) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1356) static inline int mctime_update_needed(const struct inode *inode,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1357) const struct timespec64 *now)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1358) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1359) if (!timespec64_equal(&inode->i_mtime, now) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1360) !timespec64_equal(&inode->i_ctime, now))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1361) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1362) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1363) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1364)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1365) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1366) * ubifs_update_time - update time of inode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1367) * @inode: inode to update
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1368) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1369) * This function updates time of the inode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1370) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1371) int ubifs_update_time(struct inode *inode, struct timespec64 *time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1372) int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1373) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1374) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1375) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1376) struct ubifs_budget_req req = { .dirtied_ino = 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1377) .dirtied_ino_d = ALIGN(ui->data_len, 8) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1378) int err, release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1379)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1380) if (!IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1381) return generic_update_time(inode, time, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1382)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1383) err = ubifs_budget_space(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1384) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1385) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1386)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1387) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1388) if (flags & S_ATIME)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1389) inode->i_atime = *time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1390) if (flags & S_CTIME)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1391) inode->i_ctime = *time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1392) if (flags & S_MTIME)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1393) inode->i_mtime = *time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1394)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1395) release = ui->dirty;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1396) __mark_inode_dirty(inode, I_DIRTY_SYNC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1397) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1398) if (release)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1399) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1400) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1401) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1402)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1403) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1404) * update_mctime - update mtime and ctime of an inode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1405) * @inode: inode to update
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1406) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1407) * This function updates mtime and ctime of the inode if it is not equivalent to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1408) * current time. Returns zero in case of success and a negative error code in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1409) * case of failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1410) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1411) static int update_mctime(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1412) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1413) struct timespec64 now = current_time(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1414) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1415) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1416)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1417) if (mctime_update_needed(inode, &now)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1418) int err, release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1419) struct ubifs_budget_req req = { .dirtied_ino = 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1420) .dirtied_ino_d = ALIGN(ui->data_len, 8) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1421)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1422) err = ubifs_budget_space(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1423) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1424) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1425)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1426) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1427) inode->i_mtime = inode->i_ctime = current_time(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1428) release = ui->dirty;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1429) mark_inode_dirty_sync(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1430) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1431) if (release)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1432) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1433) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1434)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1435) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1436) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1437)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1438) static ssize_t ubifs_write_iter(struct kiocb *iocb, struct iov_iter *from)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1439) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1440) int err = update_mctime(file_inode(iocb->ki_filp));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1441) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1442) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1443)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1444) return generic_file_write_iter(iocb, from);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1445) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1446)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1447) static int ubifs_set_page_dirty(struct page *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1448) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1449) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1450) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1451) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1452)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1453) ret = __set_page_dirty_nobuffers(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1454) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1455) * An attempt to dirty a page without budgeting for it - should not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1456) * happen.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1457) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1458) ubifs_assert(c, ret == 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1459) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1460) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1461)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1462) #ifdef CONFIG_MIGRATION
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1463) static int ubifs_migrate_page(struct address_space *mapping,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1464) struct page *newpage, struct page *page, enum migrate_mode mode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1465) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1466) int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1467)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1468) rc = migrate_page_move_mapping(mapping, newpage, page, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1469) if (rc != MIGRATEPAGE_SUCCESS)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1470) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1471)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1472) if (PagePrivate(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1473) detach_page_private(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1474) attach_page_private(newpage, (void *)1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1475) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1476)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1477) if (mode != MIGRATE_SYNC_NO_COPY)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1478) migrate_page_copy(newpage, page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1479) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1480) migrate_page_states(newpage, page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1481) return MIGRATEPAGE_SUCCESS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1482) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1483) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1484)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1485) static int ubifs_releasepage(struct page *page, gfp_t unused_gfp_flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1486) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1487) struct inode *inode = page->mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1488) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1489)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1490) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1491) * An attempt to release a dirty page without budgeting for it - should
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1492) * not happen.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1493) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1494) if (PageWriteback(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1495) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1496) ubifs_assert(c, PagePrivate(page));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1497) ubifs_assert(c, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1498) detach_page_private(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1499) ClearPageChecked(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1500) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1501) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1502)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1503) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1504) * mmap()d file has taken write protection fault and is being made writable.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1505) * UBIFS must ensure page is budgeted for.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1506) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1507) static vm_fault_t ubifs_vm_page_mkwrite(struct vm_fault *vmf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1508) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1509) struct page *page = vmf->page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1510) struct inode *inode = file_inode(vmf->vma->vm_file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1511) struct ubifs_info *c = inode->i_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1512) struct timespec64 now = current_time(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1513) struct ubifs_budget_req req = { .new_page = 1 };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1514) int err, update_time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1515)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1516) dbg_gen("ino %lu, pg %lu, i_size %lld", inode->i_ino, page->index,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1517) i_size_read(inode));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1518) ubifs_assert(c, !c->ro_media && !c->ro_mount);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1519)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1520) if (unlikely(c->ro_error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1521) return VM_FAULT_SIGBUS; /* -EROFS */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1522)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1523) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1524) * We have not locked @page so far so we may budget for changing the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1525) * page. Note, we cannot do this after we locked the page, because
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1526) * budgeting may cause write-back which would cause deadlock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1527) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1528) * At the moment we do not know whether the page is dirty or not, so we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1529) * assume that it is not and budget for a new page. We could look at
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1530) * the @PG_private flag and figure this out, but we may race with write
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1531) * back and the page state may change by the time we lock it, so this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1532) * would need additional care. We do not bother with this at the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1533) * moment, although it might be good idea to do. Instead, we allocate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1534) * budget for a new page and amend it later on if the page was in fact
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1535) * dirty.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1536) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1537) * The budgeting-related logic of this function is similar to what we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1538) * do in 'ubifs_write_begin()' and 'ubifs_write_end()'. Glance there
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1539) * for more comments.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1540) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1541) update_time = mctime_update_needed(inode, &now);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1542) if (update_time)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1543) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1544) * We have to change inode time stamp which requires extra
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1545) * budgeting.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1546) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1547) req.dirtied_ino = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1548)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1549) err = ubifs_budget_space(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1550) if (unlikely(err)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1551) if (err == -ENOSPC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1552) ubifs_warn(c, "out of space for mmapped file (inode number %lu)",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1553) inode->i_ino);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1554) return VM_FAULT_SIGBUS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1555) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1556)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1557) lock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1558) if (unlikely(page->mapping != inode->i_mapping ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1559) page_offset(page) > i_size_read(inode))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1560) /* Page got truncated out from underneath us */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1561) goto sigbus;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1562) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1563)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1564) if (PagePrivate(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1565) release_new_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1566) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1567) if (!PageChecked(page))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1568) ubifs_convert_page_budget(c);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1569) attach_page_private(page, (void *)1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1570) atomic_long_inc(&c->dirty_pg_cnt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1571) __set_page_dirty_nobuffers(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1572) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1573)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1574) if (update_time) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1575) int release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1576) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1577)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1578) mutex_lock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1579) inode->i_mtime = inode->i_ctime = current_time(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1580) release = ui->dirty;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1581) mark_inode_dirty_sync(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1582) mutex_unlock(&ui->ui_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1583) if (release)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1584) ubifs_release_dirty_inode_budget(c, ui);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1585) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1586)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1587) wait_for_stable_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1588) return VM_FAULT_LOCKED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1589)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1590) sigbus:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1591) unlock_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1592) ubifs_release_budget(c, &req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1593) return VM_FAULT_SIGBUS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1594) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1595)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1596) static const struct vm_operations_struct ubifs_file_vm_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1597) .fault = filemap_fault,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1598) .map_pages = filemap_map_pages,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1599) .page_mkwrite = ubifs_vm_page_mkwrite,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1600) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1601)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1602) static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1603) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1604) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1605)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1606) err = generic_file_mmap(file, vma);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1607) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1608) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1609) vma->vm_ops = &ubifs_file_vm_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1610)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1611) if (IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1612) file_accessed(file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1613)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1614) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1615) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1616)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1617) static const char *ubifs_get_link(struct dentry *dentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1618) struct inode *inode,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1619) struct delayed_call *done)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1620) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1621) struct ubifs_inode *ui = ubifs_inode(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1622)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1623) if (!IS_ENCRYPTED(inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1624) return ui->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1625)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1626) if (!dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1627) return ERR_PTR(-ECHILD);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1628)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1629) return fscrypt_get_symlink(inode, ui->data, ui->data_len, done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1630) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1631)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1632) static int ubifs_symlink_getattr(const struct path *path, struct kstat *stat,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1633) u32 request_mask, unsigned int query_flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1634) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1635) ubifs_getattr(path, stat, request_mask, query_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1636)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1637) if (IS_ENCRYPTED(d_inode(path->dentry)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1638) return fscrypt_symlink_getattr(path, stat);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1639) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1640) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1641)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1642) const struct address_space_operations ubifs_file_address_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1643) .readpage = ubifs_readpage,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1644) .writepage = ubifs_writepage,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1645) .write_begin = ubifs_write_begin,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1646) .write_end = ubifs_write_end,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1647) .invalidatepage = ubifs_invalidatepage,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1648) .set_page_dirty = ubifs_set_page_dirty,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1649) #ifdef CONFIG_MIGRATION
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1650) .migratepage = ubifs_migrate_page,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1651) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1652) .releasepage = ubifs_releasepage,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1653) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1654)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1655) const struct inode_operations ubifs_file_inode_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1656) .setattr = ubifs_setattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1657) .getattr = ubifs_getattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1658) #ifdef CONFIG_UBIFS_FS_XATTR
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1659) .listxattr = ubifs_listxattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1660) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1661) .update_time = ubifs_update_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1662) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1663)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1664) const struct inode_operations ubifs_symlink_inode_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1665) .get_link = ubifs_get_link,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1666) .setattr = ubifs_setattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1667) .getattr = ubifs_symlink_getattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1668) #ifdef CONFIG_UBIFS_FS_XATTR
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1669) .listxattr = ubifs_listxattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1670) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1671) .update_time = ubifs_update_time,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1672) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1673)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1674) const struct file_operations ubifs_file_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1675) .llseek = generic_file_llseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1676) .read_iter = generic_file_read_iter,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1677) .write_iter = ubifs_write_iter,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1678) .mmap = ubifs_file_mmap,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1679) .fsync = ubifs_fsync,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1680) .unlocked_ioctl = ubifs_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1681) .splice_read = generic_file_splice_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1682) .splice_write = iter_file_splice_write,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1683) .open = fscrypt_file_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1684) #ifdef CONFIG_COMPAT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1685) .compat_ioctl = ubifs_compat_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1686) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1687) };
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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