^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) * Copyright (C) 2011 Novell Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (C) 2016 Red Hat, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/mount.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/cred.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/xattr.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/exportfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/uuid.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/namei.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/ratelimit.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include "overlayfs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) int ovl_want_write(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) return mnt_want_write(ovl_upper_mnt(ofs));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) void ovl_drop_write(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) mnt_drop_write(ovl_upper_mnt(ofs));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) struct dentry *ovl_workdir(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) return ofs->workdir;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) const struct cred *ovl_override_creds(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) struct ovl_fs *ofs = sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) if (!ofs->config.override_creds)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) return override_creds(ofs->creator_cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) void ovl_revert_creds(struct super_block *sb, const struct cred *old_cred)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) if (old_cred)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) revert_creds(old_cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * Check if underlying fs supports file handles and try to determine encoding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) * type, in order to deduce maximum inode number used by fs.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) * Return 0 if file handles are not supported.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) * Return 1 (FILEID_INO32_GEN) if fs uses the default 32bit inode encoding.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * Return -1 if fs uses a non default encoding with unknown inode size.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) int ovl_can_decode_fh(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) if (!sb->s_export_op || !sb->s_export_op->fh_to_dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) return sb->s_export_op->encode_fh ? -1 : FILEID_INO32_GEN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) struct dentry *ovl_indexdir(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) struct ovl_fs *ofs = sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) return ofs->indexdir;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) /* Index all files on copy up. For now only enabled for NFS export */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) bool ovl_index_all(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) struct ovl_fs *ofs = sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) return ofs->config.nfs_export && ofs->config.index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) /* Verify lower origin on lookup. For now only enabled for NFS export */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) bool ovl_verify_lower(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) struct ovl_fs *ofs = sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) return ofs->config.nfs_export && ofs->config.index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) struct ovl_entry *ovl_alloc_entry(unsigned int numlower)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) size_t size = offsetof(struct ovl_entry, lowerstack[numlower]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) struct ovl_entry *oe = kzalloc(size, GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) if (oe)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) oe->numlower = numlower;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) return oe;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) bool ovl_dentry_remote(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) return dentry->d_flags &
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) (DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *upperdentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) unsigned int mask)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) struct ovl_entry *oe = OVL_E(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) unsigned int i, flags = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) if (upperdentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) flags |= upperdentry->d_flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) for (i = 0; i < oe->numlower; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) flags |= oe->lowerstack[i].dentry->d_flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) spin_lock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) dentry->d_flags &= ~mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) dentry->d_flags |= flags & mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) bool ovl_dentry_weird(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) return dentry->d_flags & (DCACHE_NEED_AUTOMOUNT |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) DCACHE_MANAGE_TRANSIT |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) DCACHE_OP_HASH |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) DCACHE_OP_COMPARE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) enum ovl_path_type ovl_path_type(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct ovl_entry *oe = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) enum ovl_path_type type = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) if (ovl_dentry_upper(dentry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) type = __OVL_PATH_UPPER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) * Non-dir dentry can hold lower dentry of its copy up origin.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) if (oe->numlower) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) if (ovl_test_flag(OVL_CONST_INO, d_inode(dentry)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) type |= __OVL_PATH_ORIGIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) if (d_is_dir(dentry) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) !ovl_has_upperdata(d_inode(dentry)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) type |= __OVL_PATH_MERGE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) if (oe->numlower > 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) type |= __OVL_PATH_MERGE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) return type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) void ovl_path_upper(struct dentry *dentry, struct path *path)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) path->mnt = ovl_upper_mnt(ofs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) path->dentry = ovl_dentry_upper(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) void ovl_path_lower(struct dentry *dentry, struct path *path)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) struct ovl_entry *oe = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) if (oe->numlower) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) path->mnt = oe->lowerstack[0].layer->mnt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) path->dentry = oe->lowerstack[0].dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) *path = (struct path) { };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) void ovl_path_lowerdata(struct dentry *dentry, struct path *path)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) struct ovl_entry *oe = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) if (oe->numlower) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) path->mnt = oe->lowerstack[oe->numlower - 1].layer->mnt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) path->dentry = oe->lowerstack[oe->numlower - 1].dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) *path = (struct path) { };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) }
^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) enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) enum ovl_path_type type = ovl_path_type(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) if (!OVL_TYPE_UPPER(type))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) ovl_path_lower(dentry, path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) ovl_path_upper(dentry, path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) return type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) struct dentry *ovl_dentry_upper(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) return ovl_upperdentry_dereference(OVL_I(d_inode(dentry)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) struct dentry *ovl_dentry_lower(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) struct ovl_entry *oe = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) return oe->numlower ? oe->lowerstack[0].dentry : NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) const struct ovl_layer *ovl_layer_lower(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) struct ovl_entry *oe = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) return oe->numlower ? oe->lowerstack[0].layer : NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) * ovl_dentry_lower() could return either a data dentry or metacopy dentry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) * dependig on what is stored in lowerstack[0]. At times we need to find
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) * lower dentry which has data (and not metacopy dentry). This helper
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) * returns the lower data dentry.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) struct dentry *ovl_dentry_lowerdata(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) struct ovl_entry *oe = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) return oe->numlower ? oe->lowerstack[oe->numlower - 1].dentry : NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) struct dentry *ovl_dentry_real(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) return ovl_dentry_upper(dentry) ?: ovl_dentry_lower(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) struct dentry *ovl_i_dentry_upper(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) return ovl_upperdentry_dereference(OVL_I(inode));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) struct inode *ovl_inode_upper(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) struct dentry *upperdentry = ovl_i_dentry_upper(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) return upperdentry ? d_inode(upperdentry) : NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) struct inode *ovl_inode_lower(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) return OVL_I(inode)->lower;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) struct inode *ovl_inode_real(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) return ovl_inode_upper(inode) ?: ovl_inode_lower(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) /* Return inode which contains lower data. Do not return metacopy */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) struct inode *ovl_inode_lowerdata(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) if (WARN_ON(!S_ISREG(inode->i_mode)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) return OVL_I(inode)->lowerdata ?: ovl_inode_lower(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) /* Return real inode which contains data. Does not return metacopy inode */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) struct inode *ovl_inode_realdata(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) struct inode *upperinode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) upperinode = ovl_inode_upper(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) if (upperinode && ovl_has_upperdata(inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) return upperinode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) return ovl_inode_lowerdata(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) struct ovl_dir_cache *ovl_dir_cache(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) return OVL_I(inode)->cache;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) void ovl_set_dir_cache(struct inode *inode, struct ovl_dir_cache *cache)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) OVL_I(inode)->cache = cache;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) void ovl_dentry_set_flag(unsigned long flag, struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) set_bit(flag, &OVL_E(dentry)->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) void ovl_dentry_clear_flag(unsigned long flag, struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) clear_bit(flag, &OVL_E(dentry)->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) bool ovl_dentry_test_flag(unsigned long flag, struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) return test_bit(flag, &OVL_E(dentry)->flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) bool ovl_dentry_is_opaque(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) return ovl_dentry_test_flag(OVL_E_OPAQUE, dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) bool ovl_dentry_is_whiteout(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) return !dentry->d_inode && ovl_dentry_is_opaque(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) void ovl_dentry_set_opaque(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) ovl_dentry_set_flag(OVL_E_OPAQUE, dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) * For hard links and decoded file handles, it's possible for ovl_dentry_upper()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) * to return positive, while there's no actual upper alias for the inode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) * Copy up code needs to know about the existence of the upper alias, so it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) * can't use ovl_dentry_upper().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) bool ovl_dentry_has_upper_alias(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) return ovl_dentry_test_flag(OVL_E_UPPER_ALIAS, dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) void ovl_dentry_set_upper_alias(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) ovl_dentry_set_flag(OVL_E_UPPER_ALIAS, dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) static bool ovl_should_check_upperdata(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) if (!S_ISREG(inode->i_mode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) if (!ovl_inode_lower(inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) bool ovl_has_upperdata(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) if (!ovl_should_check_upperdata(inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) if (!ovl_test_flag(OVL_UPPERDATA, inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) * Pairs with smp_wmb() in ovl_set_upperdata(). Main user of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) * ovl_has_upperdata() is ovl_copy_up_meta_inode_data(). Make sure
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) * if setting of OVL_UPPERDATA is visible, then effects of writes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) * before that are visible too.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) smp_rmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) void ovl_set_upperdata(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) * Pairs with smp_rmb() in ovl_has_upperdata(). Make sure
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) * if OVL_UPPERDATA flag is visible, then effects of write operations
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) * before it are visible as well.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) ovl_set_flag(OVL_UPPERDATA, inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) /* Caller should hold ovl_inode->lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) bool ovl_dentry_needs_data_copy_up_locked(struct dentry *dentry, int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) if (!ovl_open_flags_need_copy_up(flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) return !ovl_test_flag(OVL_UPPERDATA, d_inode(dentry));
^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) bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) if (!ovl_open_flags_need_copy_up(flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) return !ovl_has_upperdata(d_inode(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) bool ovl_redirect_dir(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) struct ovl_fs *ofs = sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) return ofs->config.redirect_dir && !ofs->noxattr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) const char *ovl_dentry_get_redirect(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) return OVL_I(d_inode(dentry))->redirect;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) struct ovl_inode *oi = OVL_I(d_inode(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) kfree(oi->redirect);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) oi->redirect = redirect;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) void ovl_inode_update(struct inode *inode, struct dentry *upperdentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) struct inode *upperinode = d_inode(upperdentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) WARN_ON(OVL_I(inode)->__upperdentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) * Make sure upperdentry is consistent before making it visible
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) OVL_I(inode)->__upperdentry = upperdentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) if (inode_unhashed(inode)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) inode->i_private = upperinode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) __insert_inode_hash(inode, (unsigned long) upperinode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) static void ovl_dir_version_inc(struct dentry *dentry, bool impurity)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) WARN_ON(!inode_is_locked(inode));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) WARN_ON(!d_is_dir(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) * Version is used by readdir code to keep cache consistent.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) * For merge dirs (or dirs with origin) all changes need to be noted.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) * For non-merge dirs, cache contains only impure entries (i.e. ones
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) * which have been copied up and have origins), so only need to note
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) * changes to impure entries.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) if (!ovl_dir_is_real(dentry) || impurity)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) OVL_I(inode)->version++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) void ovl_dir_modified(struct dentry *dentry, bool impurity)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) /* Copy mtime/ctime */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) ovl_copyattr(d_inode(ovl_dentry_upper(dentry)), d_inode(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) ovl_dir_version_inc(dentry, impurity);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) u64 ovl_dentry_version_get(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) WARN_ON(!inode_is_locked(inode));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) return OVL_I(inode)->version;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) bool ovl_is_whiteout(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) struct inode *inode = dentry->d_inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) return inode && IS_WHITEOUT(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) struct file *ovl_path_open(struct path *path, int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) struct inode *inode = d_inode(path->dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) int err, acc_mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) if (flags & ~(O_ACCMODE | O_LARGEFILE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) switch (flags & O_ACCMODE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) case O_RDONLY:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) acc_mode = MAY_READ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) case O_WRONLY:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) acc_mode = MAY_WRITE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) err = inode_permission(inode, acc_mode | MAY_OPEN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) return ERR_PTR(err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) /* O_NOATIME is an optimization, don't fail if not permitted */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) if (inode_owner_or_capable(inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) flags |= O_NOATIME;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) return dentry_open(path, flags, current_cred());
^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) /* Caller should hold ovl_inode->lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) static bool ovl_already_copied_up_locked(struct dentry *dentry, int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) bool disconnected = dentry->d_flags & DCACHE_DISCONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) if (ovl_dentry_upper(dentry) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) (ovl_dentry_has_upper_alias(dentry) || disconnected) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) !ovl_dentry_needs_data_copy_up_locked(dentry, flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) bool ovl_already_copied_up(struct dentry *dentry, int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) bool disconnected = dentry->d_flags & DCACHE_DISCONNECTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) * Check if copy-up has happened as well as for upper alias (in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) * case of hard links) is there.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) * Both checks are lockless:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) * - false negatives: will recheck under oi->lock
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) * - false positives:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) * + ovl_dentry_upper() uses memory barriers to ensure the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) * upper dentry is up-to-date
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) * + ovl_dentry_has_upper_alias() relies on locking of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) * upper parent i_rwsem to prevent reordering copy-up
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) * with rename.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) if (ovl_dentry_upper(dentry) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) (ovl_dentry_has_upper_alias(dentry) || disconnected) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) !ovl_dentry_needs_data_copy_up(dentry, flags))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) int ovl_copy_up_start(struct dentry *dentry, int flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) err = ovl_inode_lock_interruptible(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) if (!err && ovl_already_copied_up_locked(dentry, flags)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) err = 1; /* Already copied up */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) ovl_inode_unlock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) void ovl_copy_up_end(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) ovl_inode_unlock(d_inode(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) bool ovl_check_origin_xattr(struct ovl_fs *ofs, struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) ssize_t res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_ORIGIN, NULL, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) /* Zero size value means "copied up but origin unknown" */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) if (res >= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) bool ovl_check_dir_xattr(struct super_block *sb, struct dentry *dentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) enum ovl_xattr ox)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) ssize_t res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) char val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) if (!d_is_dir(dentry))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) res = ovl_do_getxattr(OVL_FS(sb), dentry, ox, &val, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) if (res == 1 && val == 'y')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) #define OVL_XATTR_OPAQUE_POSTFIX "opaque"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) #define OVL_XATTR_REDIRECT_POSTFIX "redirect"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) #define OVL_XATTR_ORIGIN_POSTFIX "origin"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) #define OVL_XATTR_IMPURE_POSTFIX "impure"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) #define OVL_XATTR_NLINK_POSTFIX "nlink"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) #define OVL_XATTR_UPPER_POSTFIX "upper"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) #define OVL_XATTR_METACOPY_POSTFIX "metacopy"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) #define OVL_XATTR_TAB_ENTRY(x) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) [x] = OVL_XATTR_PREFIX x ## _POSTFIX
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) const char *ovl_xattr_table[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) OVL_XATTR_TAB_ENTRY(OVL_XATTR_OPAQUE),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) OVL_XATTR_TAB_ENTRY(OVL_XATTR_REDIRECT),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) OVL_XATTR_TAB_ENTRY(OVL_XATTR_ORIGIN),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) OVL_XATTR_TAB_ENTRY(OVL_XATTR_IMPURE),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) OVL_XATTR_TAB_ENTRY(OVL_XATTR_NLINK),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) OVL_XATTR_TAB_ENTRY(OVL_XATTR_UPPER),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) OVL_XATTR_TAB_ENTRY(OVL_XATTR_METACOPY),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) int ovl_check_setxattr(struct dentry *dentry, struct dentry *upperdentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) enum ovl_xattr ox, const void *value, size_t size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) int xerr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) if (ofs->noxattr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) return xerr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) err = ovl_do_setxattr(ofs, upperdentry, ox, value, size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) if (err == -EOPNOTSUPP) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) pr_warn("cannot set %s xattr on upper\n", ovl_xattr(ofs, ox));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) ofs->noxattr = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) return xerr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) return err;
^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) int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) if (ovl_test_flag(OVL_IMPURE, d_inode(dentry)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) * Do not fail when upper doesn't support xattrs.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) * Upper inodes won't have origin nor redirect xattr anyway.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) err = ovl_check_setxattr(dentry, upperdentry, OVL_XATTR_IMPURE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640) "y", 1, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) if (!err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) ovl_set_flag(OVL_IMPURE, d_inode(dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) * Caller must hold a reference to inode to prevent it from being freed while
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) * it is marked inuse.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) bool ovl_inuse_trylock(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) bool locked = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) spin_lock(&inode->i_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) if (!(inode->i_state & I_OVL_INUSE)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) inode->i_state |= I_OVL_INUSE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) locked = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) spin_unlock(&inode->i_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) return locked;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) void ovl_inuse_unlock(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) if (dentry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) spin_lock(&inode->i_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) WARN_ON(!(inode->i_state & I_OVL_INUSE));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) inode->i_state &= ~I_OVL_INUSE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) spin_unlock(&inode->i_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) bool ovl_is_inuse(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) bool inuse;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) spin_lock(&inode->i_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) inuse = (inode->i_state & I_OVL_INUSE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) spin_unlock(&inode->i_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) return inuse;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) * Does this overlay dentry need to be indexed on copy up?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) bool ovl_need_index(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) struct dentry *lower = ovl_dentry_lower(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) if (!lower || !ovl_indexdir(dentry->d_sb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) /* Index all files for NFS export and consistency verification */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) if (ovl_index_all(dentry->d_sb))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) /* Index only lower hardlinks on copy up */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) if (!d_is_dir(lower) && d_inode(lower)->i_nlink > 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) /* Caller must hold OVL_I(inode)->lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) static void ovl_cleanup_index(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) struct dentry *indexdir = ovl_indexdir(dentry->d_sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) struct inode *dir = indexdir->d_inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) struct dentry *lowerdentry = ovl_dentry_lower(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) struct dentry *upperdentry = ovl_dentry_upper(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) struct dentry *index = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) struct inode *inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) struct qstr name = { };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) err = ovl_get_index_name(lowerdentry, &name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) goto fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) inode = d_inode(upperdentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) if (!S_ISDIR(inode->i_mode) && inode->i_nlink != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) pr_warn_ratelimited("cleanup linked index (%pd2, ino=%lu, nlink=%u)\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) upperdentry, inode->i_ino, inode->i_nlink);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) * We either have a bug with persistent union nlink or a lower
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) * hardlink was added while overlay is mounted. Adding a lower
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) * hardlink and then unlinking all overlay hardlinks would drop
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) * overlay nlink to zero before all upper inodes are unlinked.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) * As a safety measure, when that situation is detected, set
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) * the overlay nlink to the index inode nlink minus one for the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) * index entry itself.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) set_nlink(d_inode(dentry), inode->i_nlink - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) ovl_set_nlink_upper(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) inode_lock_nested(dir, I_MUTEX_PARENT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) index = lookup_one_len(name.name, indexdir, name.len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) err = PTR_ERR(index);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) if (IS_ERR(index)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) index = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) } else if (ovl_index_all(dentry->d_sb)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) /* Whiteout orphan index to block future open by handle */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) err = ovl_cleanup_and_whiteout(OVL_FS(dentry->d_sb),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) dir, index);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) /* Cleanup orphan index entries */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) err = ovl_cleanup(dir, index);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) inode_unlock(dir);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) goto fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) kfree(name.name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) dput(index);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) fail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) pr_err("cleanup index of '%pd2' failed (%i)\n", dentry, err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) * Operations that change overlay inode and upper inode nlink need to be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) * synchronized with copy up for persistent nlink accounting.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) int ovl_nlink_start(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) const struct cred *old_cred;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) if (WARN_ON(!inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) return -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) * With inodes index is enabled, we store the union overlay nlink
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) * in an xattr on the index inode. When whiting out an indexed lower,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) * we need to decrement the overlay persistent nlink, but before the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) * first copy up, we have no upper index inode to store the xattr.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) * As a workaround, before whiteout/rename over an indexed lower,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) * copy up to create the upper index. Creating the upper index will
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) * initialize the overlay nlink, so it could be dropped if unlink
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) * or rename succeeds.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) * TODO: implement metadata only index copy up when called with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) * ovl_copy_up_flags(dentry, O_PATH).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) if (ovl_need_index(dentry) && !ovl_dentry_has_upper_alias(dentry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) err = ovl_copy_up(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) err = ovl_inode_lock_interruptible(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) if (d_is_dir(dentry) || !ovl_test_flag(OVL_INDEX, inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) old_cred = ovl_override_creds(dentry->d_sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815) * The overlay inode nlink should be incremented/decremented IFF the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) * upper operation succeeds, along with nlink change of upper inode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817) * Therefore, before link/unlink/rename, we store the union nlink
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) * value relative to the upper inode nlink in an upper inode xattr.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) err = ovl_set_nlink_upper(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) ovl_revert_creds(dentry->d_sb, old_cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) ovl_inode_unlock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) void ovl_nlink_end(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) struct inode *inode = d_inode(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) if (ovl_test_flag(OVL_INDEX, inode) && inode->i_nlink == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) const struct cred *old_cred;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) old_cred = ovl_override_creds(dentry->d_sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838) ovl_cleanup_index(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839) ovl_revert_creds(dentry->d_sb, old_cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842) ovl_inode_unlock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) /* Workdir should not be the same as upperdir */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) if (workdir == upperdir)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851) /* Workdir should not be subdir of upperdir and vice versa */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852) if (lock_rename(workdir, upperdir) != NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) goto err_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) err_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858) unlock_rename(workdir, upperdir);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859) err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) pr_err("failed to lock workdir+upperdir\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861) return -EIO;
^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) /* err < 0, 0 if no metacopy xattr, 1 if metacopy xattr found */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) int ovl_check_metacopy_xattr(struct ovl_fs *ofs, struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) ssize_t res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) /* Only regular files can have metacopy xattr */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870) if (!S_ISREG(d_inode(dentry)->i_mode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873) res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_METACOPY, NULL, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) if (res < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) if (res == -ENODATA || res == -EOPNOTSUPP)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882) pr_warn_ratelimited("failed to get metacopy (%zi)\n", res);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) return res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886) bool ovl_is_metacopy_dentry(struct dentry *dentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888) struct ovl_entry *oe = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890) if (!d_is_reg(dentry))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) if (ovl_dentry_upper(dentry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894) if (!ovl_has_upperdata(d_inode(dentry)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899) return (oe->numlower > 1);
^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) char *ovl_get_redirect_xattr(struct ovl_fs *ofs, struct dentry *dentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) int padding)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905) int res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906) char *s, *next, *buf = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_REDIRECT, NULL, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909) if (res == -ENODATA || res == -EOPNOTSUPP)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) if (res < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912) goto fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913) if (res == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914) goto invalid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916) buf = kzalloc(res + padding + 1, GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917) if (!buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) return ERR_PTR(-ENOMEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920) res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_REDIRECT, buf, res);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) if (res < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) goto fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) if (res == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) goto invalid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) if (buf[0] == '/') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927) for (s = buf; *s++ == '/'; s = next) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) next = strchrnul(s, '/');
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929) if (s == next)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930) goto invalid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933) if (strchr(buf, '/') != NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) goto invalid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937) return buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) invalid:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) pr_warn_ratelimited("invalid redirect (%s)\n", buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940) res = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941) goto err_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942) fail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943) pr_warn_ratelimited("failed to get redirect (%i)\n", res);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944) err_free:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945) kfree(buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946) return ERR_PTR(res);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950) * ovl_sync_status() - Check fs sync status for volatile mounts
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952) * Returns 1 if this is not a volatile mount and a real sync is required.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) * Returns 0 if syncing can be skipped because mount is volatile, and no errors
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955) * have occurred on the upperdir since the mount.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) * Returns -errno if it is a volatile mount, and the error that occurred since
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958) * the last mount. If the error code changes, it'll return the latest error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) * code.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962) int ovl_sync_status(struct ovl_fs *ofs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) struct vfsmount *mnt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) if (ovl_should_sync(ofs))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) mnt = ovl_upper_mnt(ofs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970) if (!mnt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) return errseq_check(&mnt->mnt_sb->s_wb_err, ofs->errseq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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