forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
461 lines
10 KiB
461 lines
10 KiB
// 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 <linux/blkdev.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; |
|
} |
|
|
|
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 *bh; |
|
sector_t blknr, last_blknr; |
|
int i; |
|
|
|
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 */ |
|
for (i = blknr; i < last_blknr; i++) { |
|
bh = sb_getblk(sb, i); |
|
if (!bh) |
|
return -ENOMEM; |
|
|
|
memset(bh->b_data, 0, sb->s_blocksize); |
|
set_buffer_uptodate(bh); |
|
mark_buffer_dirty(bh); |
|
brelse(bh); |
|
} |
|
|
|
if (IS_DIRSYNC(dir)) |
|
return sync_blockdev_range(sb->s_bdev, |
|
EXFAT_BLK_TO_B(blknr, sb), |
|
EXFAT_BLK_TO_B(last_blknr, sb) - 1); |
|
|
|
return 0; |
|
} |
|
|
|
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)", |
|
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; |
|
}
|
|
|