Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  *  linux/fs/ext2/file.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (C) 1992, 1993, 1994, 1995
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * Remy Card (card@masi.ibp.fr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  * Laboratoire MASI - Institut Blaise Pascal
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  * Universite Pierre et Marie Curie (Paris VI)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  *  from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12)  *  linux/fs/minix/file.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14)  *  Copyright (C) 1991, 1992  Linus Torvalds
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16)  *  ext2 fs regular file handling primitives
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18)  *  64-bit file support on 64-bit platforms by Jakub Jelinek
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19)  * 	(jj@sunsite.ms.mff.cuni.cz)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include <linux/time.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #include <linux/pagemap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #include <linux/dax.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) #include <linux/quotaops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) #include <linux/iomap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) #include <linux/uio.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) #include "ext2.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) #include "xattr.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) #include "acl.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) #ifdef CONFIG_FS_DAX
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	struct inode *inode = iocb->ki_filp->f_mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	ssize_t ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	if (!iov_iter_count(to))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 		return 0; /* skip atime */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	inode_lock_shared(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	ret = dax_iomap_rw(iocb, to, &ext2_iomap_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	inode_unlock_shared(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	file_accessed(iocb->ki_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) static ssize_t ext2_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	struct file *file = iocb->ki_filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	struct inode *inode = file->f_mapping->host;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	ssize_t ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	inode_lock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	ret = generic_write_checks(iocb, from);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	if (ret <= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 		goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	ret = file_remove_privs(file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 		goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	ret = file_update_time(file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 		goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	ret = dax_iomap_rw(iocb, from, &ext2_iomap_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		i_size_write(inode, iocb->ki_pos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 		mark_inode_dirty(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 	inode_unlock(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	if (ret > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		ret = generic_write_sync(iocb, ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80)  * The lock ordering for ext2 DAX fault paths is:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82)  * mmap_lock (MM)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83)  *   sb_start_pagefault (vfs, freeze)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84)  *     ext2_inode_info->dax_sem
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85)  *       address_space->i_mmap_rwsem or page_lock (mutually exclusive in DAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86)  *         ext2_inode_info->truncate_mutex
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88)  * The default page_lock and i_size verification done by non-DAX fault paths
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89)  * is sufficient because ext2 doesn't support hole punching.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) static vm_fault_t ext2_dax_fault(struct vm_fault *vmf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	struct inode *inode = file_inode(vmf->vma->vm_file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	struct ext2_inode_info *ei = EXT2_I(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	vm_fault_t ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	bool write = (vmf->flags & FAULT_FLAG_WRITE) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 		(vmf->vma->vm_flags & VM_SHARED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	if (write) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		sb_start_pagefault(inode->i_sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		file_update_time(vmf->vma->vm_file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 	down_read(&ei->dax_sem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	ret = dax_iomap_fault(vmf, PE_SIZE_PTE, NULL, NULL, &ext2_iomap_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	up_read(&ei->dax_sem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	if (write)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		sb_end_pagefault(inode->i_sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) static const struct vm_operations_struct ext2_dax_vm_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	.fault		= ext2_dax_fault,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	 * .huge_fault is not supported for DAX because allocation in ext2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	 * cannot be reliably aligned to huge page sizes and so pmd faults
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	 * will always fail and fail back to regular faults.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	.page_mkwrite	= ext2_dax_fault,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	.pfn_mkwrite	= ext2_dax_fault,
^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) static int ext2_file_mmap(struct file *file, struct vm_area_struct *vma)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	if (!IS_DAX(file_inode(file)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 		return generic_file_mmap(file, vma);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	file_accessed(file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 	vma->vm_ops = &ext2_dax_vm_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) #define ext2_file_mmap	generic_file_mmap
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)  * Called when filp is released. This happens when all file descriptors
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)  * for a single struct file are closed. Note that different open() calls
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)  * for the same file yield different struct file structures.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) static int ext2_release_file (struct inode * inode, struct file * filp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	if (filp->f_mode & FMODE_WRITE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 		mutex_lock(&EXT2_I(inode)->truncate_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 		ext2_discard_reservation(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 		mutex_unlock(&EXT2_I(inode)->truncate_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	struct super_block *sb = file->f_mapping->host->i_sb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	ret = generic_file_fsync(file, start, end, datasync);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	if (ret == -EIO)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 		/* We don't really know where the IO error happened... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 		ext2_error(sb, __func__,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 			   "detected IO error when writing metadata buffers");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	return ret;
^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) static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) #ifdef CONFIG_FS_DAX
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	if (IS_DAX(iocb->ki_filp->f_mapping->host))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 		return ext2_dax_read_iter(iocb, to);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	return generic_file_read_iter(iocb, to);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) #ifdef CONFIG_FS_DAX
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	if (IS_DAX(iocb->ki_filp->f_mapping->host))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 		return ext2_dax_write_iter(iocb, from);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	return generic_file_write_iter(iocb, from);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) const struct file_operations ext2_file_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	.llseek		= generic_file_llseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	.read_iter	= ext2_file_read_iter,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 	.write_iter	= ext2_file_write_iter,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 	.unlocked_ioctl = ext2_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) #ifdef CONFIG_COMPAT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	.compat_ioctl	= ext2_compat_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	.mmap		= ext2_file_mmap,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	.open		= dquot_file_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	.release	= ext2_release_file,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	.fsync		= ext2_fsync,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 	.get_unmapped_area = thp_get_unmapped_area,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 	.splice_read	= generic_file_splice_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	.splice_write	= iter_file_splice_write,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) const struct inode_operations ext2_file_inode_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 	.listxattr	= ext2_listxattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 	.getattr	= ext2_getattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 	.setattr	= ext2_setattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 	.get_acl	= ext2_get_acl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 	.set_acl	= ext2_set_acl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 	.fiemap		= ext2_fiemap,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) };