477 lines
11 KiB
C
477 lines
11 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
|
|
*/
|
|
|
|
#include <linux/slab.h>
|
|
#include <asm/unaligned.h>
|
|
#include <linux/buffer_head.h>
|
|
|
|
#include "exfat_raw.h"
|
|
#include "exfat_fs.h"
|
|
|
|
static int exfat_mirror_bh(struct super_block *sb, sector_t sec,
|
|
struct buffer_head *bh)
|
|
{
|
|
struct buffer_head *c_bh;
|
|
struct exfat_sb_info *sbi = EXFAT_SB(sb);
|
|
sector_t sec2;
|
|
int err = 0;
|
|
|
|
if (sbi->FAT2_start_sector != sbi->FAT1_start_sector) {
|
|
sec2 = sec - sbi->FAT1_start_sector + sbi->FAT2_start_sector;
|
|
c_bh = sb_getblk(sb, sec2);
|
|
if (!c_bh)
|
|
return -ENOMEM;
|
|
memcpy(c_bh->b_data, bh->b_data, sb->s_blocksize);
|
|
set_buffer_uptodate(c_bh);
|
|
mark_buffer_dirty(c_bh);
|
|
if (sb->s_flags & SB_SYNCHRONOUS)
|
|
err = sync_dirty_buffer(c_bh);
|
|
brelse(c_bh);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int __exfat_ent_get(struct super_block *sb, unsigned int loc,
|
|
unsigned int *content)
|
|
{
|
|
unsigned int off;
|
|
sector_t sec;
|
|
struct buffer_head *bh;
|
|
|
|
sec = FAT_ENT_OFFSET_SECTOR(sb, loc);
|
|
off = FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc);
|
|
|
|
bh = sb_bread(sb, sec);
|
|
if (!bh)
|
|
return -EIO;
|
|
|
|
*content = le32_to_cpu(*(__le32 *)(&bh->b_data[off]));
|
|
|
|
/* remap reserved clusters to simplify code */
|
|
if (*content > EXFAT_BAD_CLUSTER)
|
|
*content = EXFAT_EOF_CLUSTER;
|
|
|
|
brelse(bh);
|
|
return 0;
|
|
}
|
|
|
|
int exfat_ent_set(struct super_block *sb, unsigned int loc,
|
|
unsigned int content)
|
|
{
|
|
unsigned int off;
|
|
sector_t sec;
|
|
__le32 *fat_entry;
|
|
struct buffer_head *bh;
|
|
|
|
sec = FAT_ENT_OFFSET_SECTOR(sb, loc);
|
|
off = FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc);
|
|
|
|
bh = sb_bread(sb, sec);
|
|
if (!bh)
|
|
return -EIO;
|
|
|
|
fat_entry = (__le32 *)&(bh->b_data[off]);
|
|
*fat_entry = cpu_to_le32(content);
|
|
exfat_update_bh(bh, sb->s_flags & SB_SYNCHRONOUS);
|
|
exfat_mirror_bh(sb, sec, bh);
|
|
brelse(bh);
|
|
return 0;
|
|
}
|
|
|
|
static inline bool is_valid_cluster(struct exfat_sb_info *sbi,
|
|
unsigned int clus)
|
|
{
|
|
if (clus < EXFAT_FIRST_CLUSTER || sbi->num_clusters <= clus)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
int exfat_ent_get(struct super_block *sb, unsigned int loc,
|
|
unsigned int *content)
|
|
{
|
|
struct exfat_sb_info *sbi = EXFAT_SB(sb);
|
|
int err;
|
|
|
|
if (!is_valid_cluster(sbi, loc)) {
|
|
exfat_fs_error(sb, "invalid access to FAT (entry 0x%08x)",
|
|
loc);
|
|
return -EIO;
|
|
}
|
|
|
|
err = __exfat_ent_get(sb, loc, content);
|
|
if (err) {
|
|
exfat_fs_error(sb,
|
|
"failed to access to FAT (entry 0x%08x, err:%d)",
|
|
loc, err);
|
|
return err;
|
|
}
|
|
|
|
if (*content == EXFAT_FREE_CLUSTER) {
|
|
exfat_fs_error(sb,
|
|
"invalid access to FAT free cluster (entry 0x%08x)",
|
|
loc);
|
|
return -EIO;
|
|
}
|
|
|
|
if (*content == EXFAT_BAD_CLUSTER) {
|
|
exfat_fs_error(sb,
|
|
"invalid access to FAT bad cluster (entry 0x%08x)",
|
|
loc);
|
|
return -EIO;
|
|
}
|
|
|
|
if (*content != EXFAT_EOF_CLUSTER && !is_valid_cluster(sbi, *content)) {
|
|
exfat_fs_error(sb,
|
|
"invalid access to FAT (entry 0x%08x) bogus content (0x%08x)",
|
|
loc, *content);
|
|
return -EIO;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain,
|
|
unsigned int len)
|
|
{
|
|
if (!len)
|
|
return 0;
|
|
|
|
while (len > 1) {
|
|
if (exfat_ent_set(sb, chain, chain + 1))
|
|
return -EIO;
|
|
chain++;
|
|
len--;
|
|
}
|
|
|
|
if (exfat_ent_set(sb, chain, EXFAT_EOF_CLUSTER))
|
|
return -EIO;
|
|
return 0;
|
|
}
|
|
|
|
/* This function must be called with bitmap_lock held */
|
|
static int __exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct exfat_sb_info *sbi = EXFAT_SB(sb);
|
|
int cur_cmap_i, next_cmap_i;
|
|
unsigned int num_clusters = 0;
|
|
unsigned int clu;
|
|
|
|
/* invalid cluster number */
|
|
if (p_chain->dir == EXFAT_FREE_CLUSTER ||
|
|
p_chain->dir == EXFAT_EOF_CLUSTER ||
|
|
p_chain->dir < EXFAT_FIRST_CLUSTER)
|
|
return 0;
|
|
|
|
/* no cluster to truncate */
|
|
if (p_chain->size == 0)
|
|
return 0;
|
|
|
|
/* check cluster validation */
|
|
if (!is_valid_cluster(sbi, p_chain->dir)) {
|
|
exfat_err(sb, "invalid start cluster (%u)", p_chain->dir);
|
|
return -EIO;
|
|
}
|
|
|
|
clu = p_chain->dir;
|
|
|
|
cur_cmap_i = next_cmap_i =
|
|
BITMAP_OFFSET_SECTOR_INDEX(sb, CLUSTER_TO_BITMAP_ENT(clu));
|
|
|
|
if (p_chain->flags == ALLOC_NO_FAT_CHAIN) {
|
|
unsigned int last_cluster = p_chain->dir + p_chain->size - 1;
|
|
do {
|
|
bool sync = false;
|
|
|
|
if (clu < last_cluster)
|
|
next_cmap_i =
|
|
BITMAP_OFFSET_SECTOR_INDEX(sb, CLUSTER_TO_BITMAP_ENT(clu+1));
|
|
|
|
/* flush bitmap only if index would be changed or for last cluster */
|
|
if (clu == last_cluster || cur_cmap_i != next_cmap_i) {
|
|
sync = true;
|
|
cur_cmap_i = next_cmap_i;
|
|
}
|
|
|
|
exfat_clear_bitmap(inode, clu, (sync && IS_DIRSYNC(inode)));
|
|
clu++;
|
|
num_clusters++;
|
|
} while (num_clusters < p_chain->size);
|
|
} else {
|
|
do {
|
|
bool sync = false;
|
|
unsigned int n_clu = clu;
|
|
int err = exfat_get_next_cluster(sb, &n_clu);
|
|
|
|
if (err || n_clu == EXFAT_EOF_CLUSTER)
|
|
sync = true;
|
|
else
|
|
next_cmap_i =
|
|
BITMAP_OFFSET_SECTOR_INDEX(sb, CLUSTER_TO_BITMAP_ENT(n_clu));
|
|
|
|
if (cur_cmap_i != next_cmap_i) {
|
|
sync = true;
|
|
cur_cmap_i = next_cmap_i;
|
|
}
|
|
|
|
exfat_clear_bitmap(inode, clu, (sync && IS_DIRSYNC(inode)));
|
|
clu = n_clu;
|
|
num_clusters++;
|
|
|
|
if (err)
|
|
goto dec_used_clus;
|
|
} while (clu != EXFAT_EOF_CLUSTER);
|
|
}
|
|
|
|
dec_used_clus:
|
|
sbi->used_clusters -= num_clusters;
|
|
return 0;
|
|
}
|
|
|
|
int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain)
|
|
{
|
|
int ret = 0;
|
|
|
|
mutex_lock(&EXFAT_SB(inode->i_sb)->bitmap_lock);
|
|
ret = __exfat_free_cluster(inode, p_chain);
|
|
mutex_unlock(&EXFAT_SB(inode->i_sb)->bitmap_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain,
|
|
unsigned int *ret_clu)
|
|
{
|
|
unsigned int clu, next;
|
|
unsigned int count = 0;
|
|
|
|
next = p_chain->dir;
|
|
if (p_chain->flags == ALLOC_NO_FAT_CHAIN) {
|
|
*ret_clu = next + p_chain->size - 1;
|
|
return 0;
|
|
}
|
|
|
|
do {
|
|
count++;
|
|
clu = next;
|
|
if (exfat_ent_get(sb, clu, &next))
|
|
return -EIO;
|
|
} while (next != EXFAT_EOF_CLUSTER);
|
|
|
|
if (p_chain->size != count) {
|
|
exfat_fs_error(sb,
|
|
"bogus directory size (clus : ondisk(%d) != counted(%d))",
|
|
p_chain->size, count);
|
|
return -EIO;
|
|
}
|
|
|
|
*ret_clu = clu;
|
|
return 0;
|
|
}
|
|
|
|
int exfat_zeroed_cluster(struct inode *dir, unsigned int clu)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
struct exfat_sb_info *sbi = EXFAT_SB(sb);
|
|
struct buffer_head *bhs[MAX_BUF_PER_PAGE];
|
|
int nr_bhs = MAX_BUF_PER_PAGE;
|
|
sector_t blknr, last_blknr;
|
|
int err, i, n;
|
|
|
|
blknr = exfat_cluster_to_sector(sbi, clu);
|
|
last_blknr = blknr + sbi->sect_per_clus;
|
|
|
|
if (last_blknr > sbi->num_sectors && sbi->num_sectors > 0) {
|
|
exfat_fs_error_ratelimit(sb,
|
|
"%s: out of range(sect:%llu len:%u)",
|
|
__func__, (unsigned long long)blknr,
|
|
sbi->sect_per_clus);
|
|
return -EIO;
|
|
}
|
|
|
|
/* Zeroing the unused blocks on this cluster */
|
|
while (blknr < last_blknr) {
|
|
for (n = 0; n < nr_bhs && blknr < last_blknr; n++, blknr++) {
|
|
bhs[n] = sb_getblk(sb, blknr);
|
|
if (!bhs[n]) {
|
|
err = -ENOMEM;
|
|
goto release_bhs;
|
|
}
|
|
memset(bhs[n]->b_data, 0, sb->s_blocksize);
|
|
}
|
|
|
|
err = exfat_update_bhs(bhs, n, IS_DIRSYNC(dir));
|
|
if (err)
|
|
goto release_bhs;
|
|
|
|
for (i = 0; i < n; i++)
|
|
brelse(bhs[i]);
|
|
}
|
|
return 0;
|
|
|
|
release_bhs:
|
|
exfat_err(sb, "failed zeroed sect %llu\n", (unsigned long long)blknr);
|
|
for (i = 0; i < n; i++)
|
|
bforget(bhs[i]);
|
|
return err;
|
|
}
|
|
|
|
int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc,
|
|
struct exfat_chain *p_chain, bool sync_bmap)
|
|
{
|
|
int ret = -ENOSPC;
|
|
unsigned int num_clusters = 0, total_cnt;
|
|
unsigned int hint_clu, new_clu, last_clu = EXFAT_EOF_CLUSTER;
|
|
struct super_block *sb = inode->i_sb;
|
|
struct exfat_sb_info *sbi = EXFAT_SB(sb);
|
|
|
|
total_cnt = EXFAT_DATA_CLUSTER_COUNT(sbi);
|
|
|
|
if (unlikely(total_cnt < sbi->used_clusters)) {
|
|
exfat_fs_error_ratelimit(sb,
|
|
"%s: invalid used clusters(t:%u,u:%u)\n",
|
|
__func__, total_cnt, sbi->used_clusters);
|
|
return -EIO;
|
|
}
|
|
|
|
if (num_alloc > total_cnt - sbi->used_clusters)
|
|
return -ENOSPC;
|
|
|
|
mutex_lock(&sbi->bitmap_lock);
|
|
|
|
hint_clu = p_chain->dir;
|
|
/* find new cluster */
|
|
if (hint_clu == EXFAT_EOF_CLUSTER) {
|
|
if (sbi->clu_srch_ptr < EXFAT_FIRST_CLUSTER) {
|
|
exfat_err(sb, "sbi->clu_srch_ptr is invalid (%u)\n",
|
|
sbi->clu_srch_ptr);
|
|
sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;
|
|
}
|
|
|
|
hint_clu = exfat_find_free_bitmap(sb, sbi->clu_srch_ptr);
|
|
if (hint_clu == EXFAT_EOF_CLUSTER) {
|
|
ret = -ENOSPC;
|
|
goto unlock;
|
|
}
|
|
}
|
|
|
|
/* check cluster validation */
|
|
if (!is_valid_cluster(sbi, hint_clu)) {
|
|
exfat_err(sb, "hint_cluster is invalid (%u)",
|
|
hint_clu);
|
|
hint_clu = EXFAT_FIRST_CLUSTER;
|
|
if (p_chain->flags == ALLOC_NO_FAT_CHAIN) {
|
|
if (exfat_chain_cont_cluster(sb, p_chain->dir,
|
|
num_clusters)) {
|
|
ret = -EIO;
|
|
goto unlock;
|
|
}
|
|
p_chain->flags = ALLOC_FAT_CHAIN;
|
|
}
|
|
}
|
|
|
|
p_chain->dir = EXFAT_EOF_CLUSTER;
|
|
|
|
while ((new_clu = exfat_find_free_bitmap(sb, hint_clu)) !=
|
|
EXFAT_EOF_CLUSTER) {
|
|
if (new_clu != hint_clu &&
|
|
p_chain->flags == ALLOC_NO_FAT_CHAIN) {
|
|
if (exfat_chain_cont_cluster(sb, p_chain->dir,
|
|
num_clusters)) {
|
|
ret = -EIO;
|
|
goto free_cluster;
|
|
}
|
|
p_chain->flags = ALLOC_FAT_CHAIN;
|
|
}
|
|
|
|
/* update allocation bitmap */
|
|
if (exfat_set_bitmap(inode, new_clu, sync_bmap)) {
|
|
ret = -EIO;
|
|
goto free_cluster;
|
|
}
|
|
|
|
num_clusters++;
|
|
|
|
/* update FAT table */
|
|
if (p_chain->flags == ALLOC_FAT_CHAIN) {
|
|
if (exfat_ent_set(sb, new_clu, EXFAT_EOF_CLUSTER)) {
|
|
ret = -EIO;
|
|
goto free_cluster;
|
|
}
|
|
}
|
|
|
|
if (p_chain->dir == EXFAT_EOF_CLUSTER) {
|
|
p_chain->dir = new_clu;
|
|
} else if (p_chain->flags == ALLOC_FAT_CHAIN) {
|
|
if (exfat_ent_set(sb, last_clu, new_clu)) {
|
|
ret = -EIO;
|
|
goto free_cluster;
|
|
}
|
|
}
|
|
last_clu = new_clu;
|
|
|
|
if (--num_alloc == 0) {
|
|
sbi->clu_srch_ptr = hint_clu;
|
|
sbi->used_clusters += num_clusters;
|
|
|
|
p_chain->size += num_clusters;
|
|
mutex_unlock(&sbi->bitmap_lock);
|
|
return 0;
|
|
}
|
|
|
|
hint_clu = new_clu + 1;
|
|
if (hint_clu >= sbi->num_clusters) {
|
|
hint_clu = EXFAT_FIRST_CLUSTER;
|
|
|
|
if (p_chain->flags == ALLOC_NO_FAT_CHAIN) {
|
|
if (exfat_chain_cont_cluster(sb, p_chain->dir,
|
|
num_clusters)) {
|
|
ret = -EIO;
|
|
goto free_cluster;
|
|
}
|
|
p_chain->flags = ALLOC_FAT_CHAIN;
|
|
}
|
|
}
|
|
}
|
|
free_cluster:
|
|
if (num_clusters)
|
|
__exfat_free_cluster(inode, p_chain);
|
|
unlock:
|
|
mutex_unlock(&sbi->bitmap_lock);
|
|
return ret;
|
|
}
|
|
|
|
int exfat_count_num_clusters(struct super_block *sb,
|
|
struct exfat_chain *p_chain, unsigned int *ret_count)
|
|
{
|
|
unsigned int i, count;
|
|
unsigned int clu;
|
|
struct exfat_sb_info *sbi = EXFAT_SB(sb);
|
|
|
|
if (!p_chain->dir || p_chain->dir == EXFAT_EOF_CLUSTER) {
|
|
*ret_count = 0;
|
|
return 0;
|
|
}
|
|
|
|
if (p_chain->flags == ALLOC_NO_FAT_CHAIN) {
|
|
*ret_count = p_chain->size;
|
|
return 0;
|
|
}
|
|
|
|
clu = p_chain->dir;
|
|
count = 0;
|
|
for (i = EXFAT_FIRST_CLUSTER; i < sbi->num_clusters; i++) {
|
|
count++;
|
|
if (exfat_ent_get(sb, clu, &clu))
|
|
return -EIO;
|
|
if (clu == EXFAT_EOF_CLUSTER)
|
|
break;
|
|
}
|
|
|
|
*ret_count = count;
|
|
return 0;
|
|
}
|