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core.c
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core.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
*
* core.c: FAT-common core code
*/
#include <linux/version.h>
#include <linux/blkdev.h>
#include <linux/workqueue.h>
#include <linux/writeback.h>
#include <linux/kernel.h>
#include <linux/log2.h>
#include "exfat.h"
#include "core.h"
#include <asm/byteorder.h>
#include <asm/unaligned.h>
void exfat_set_sb_dirty(struct super_block *sb)
{
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 7, 0)
sb->s_dirt = 1;
#else /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 7, 0) */
struct exfat_sb_info *sbi = EXFAT_SB(sb);
sbi->s_dirt = 1;
/* Insert work */
spin_lock(&sbi->work_lock);
if (!sbi->write_super_queued) {
unsigned long delay;
delay = msecs_to_jiffies(CONFIG_EXFAT_WRITE_SB_INTERVAL_CSECS * 10);
queue_delayed_work(system_long_wq, &sbi->write_super_work, delay);
sbi->write_super_queued = 1;
}
spin_unlock(&sbi->work_lock);
#endif
}
static s32 check_type_size(void)
{
/* critical check for system requirement on size of DENTRY_T structure */
if (sizeof(DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(DOS_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(EXT_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(FILE_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(STRM_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(NAME_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(BMAP_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(CASE_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
if (sizeof(VOLM_DENTRY_T) != DENTRY_SIZE)
return -EINVAL;
return 0;
}
static s32 __fs_set_vol_flags(struct super_block *sb, u16 new_flag, s32 always_sync)
{
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
pbr64_t *bpb;
s32 err;
s32 sync = 0;
/* flags are not changed */
if (fsi->vol_flag == new_flag)
return 0;
fsi->vol_flag = new_flag;
/* skip updating volume dirty flag,
* if this volume has been mounted with read-only
*/
if (EXFAT_IS_SB_RDONLY(sb))
return 0;
if (!fsi->pbr_bh) {
err = exfat_read_sect(sb, 0, &(fsi->pbr_bh), 1);
if (err) {
EMSG("%s : failed to read boot sector\n", __func__);
return err;
}
}
bpb = (pbr64_t *)fsi->pbr_bh->b_data;
bpb->bsx.vol_flags = cpu_to_le16(new_flag);
if (always_sync)
sync = 1;
else if ((new_flag == VOL_DIRTY) && (!buffer_dirty(fsi->pbr_bh)))
sync = 1;
else
sync = 0;
err = exfat_write_sect(sb, 0, fsi->pbr_bh, sync);
if (err)
EMSG("%s : failed to modify volume flag\n", __func__);
return err;
}
static s32 fs_set_vol_flags(struct super_block *sb, u16 new_flag)
{
return __fs_set_vol_flags(sb, new_flag, 0);
}
s32 exfat_fscore_set_vol_flags(struct super_block *sb, u16 new_flag, s32 always_sync)
{
return __fs_set_vol_flags(sb, new_flag, always_sync);
}
static s32 fs_sync(struct super_block *sb, s32 do_sync)
{
s32 err;
if (!do_sync)
return 0;
err = exfat_bdev_sync_all(sb);
if (err)
EMSG("%s : failed to sync. (err:%d)\n", __func__, err);
return err;
}
/*
* Cluster Management Functions
*/
static s32 __clear_cluster(struct inode *inode, u32 clu)
{
u64 s, n;
struct super_block *sb = inode->i_sb;
u32 sect_size = (u32)sb->s_blocksize;
s32 ret = 0;
struct buffer_head *tmp_bh = NULL;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
if (IS_CLUS_FREE(clu)) { /* FAT16 root_dir */
s = fsi->root_start_sector;
n = fsi->data_start_sector;
} else {
s = CLUS_TO_SECT(fsi, clu);
n = s + fsi->sect_per_clus;
}
if (IS_DIRSYNC(inode)) {
ret = exfat_write_msect_zero(sb, s, (u64)fsi->sect_per_clus);
if (ret != -EAGAIN)
return ret;
}
/* Trying buffered zero writes
* if it doesn't have DIRSYNC or exfat_write_msect_zero() returned -EAGAIN
*/
for ( ; s < n; s++) {
#if 0
exfat_dcache_release(sb, s);
#endif
ret = exfat_read_sect(sb, s, &tmp_bh, 0);
if (ret)
goto out;
memset((u8 *)tmp_bh->b_data, 0x0, sect_size);
ret = exfat_write_sect(sb, s, tmp_bh, 0);
if (ret)
goto out;
}
out:
brelse(tmp_bh);
return ret;
}
static s32 __find_last_cluster(struct super_block *sb, CHAIN_T *p_chain, u32 *ret_clu)
{
u32 clu, next;
u32 count = 0;
next = p_chain->dir;
if (p_chain->flags == 0x03) {
*ret_clu = next + p_chain->size - 1;
return 0;
}
do {
count++;
clu = next;
if (exfat_ent_get_safe(sb, clu, &next))
return -EIO;
} while (!IS_CLUS_EOF(next));
if (p_chain->size != count) {
exfat_fs_error(sb, "bogus directory size "
"(clus : ondisk(%d) != counted(%d))",
p_chain->size, count);
exfat_debug_bug_on(1);
return -EIO;
}
*ret_clu = clu;
return 0;
}
static s32 __count_num_clusters(struct super_block *sb, CHAIN_T *p_chain, u32 *ret_count)
{
u32 i, count;
u32 clu;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
if (!p_chain->dir || IS_CLUS_EOF(p_chain->dir)) {
*ret_count = 0;
return 0;
}
if (p_chain->flags == 0x03) {
*ret_count = p_chain->size;
return 0;
}
clu = p_chain->dir;
count = 0;
for (i = CLUS_BASE; i < fsi->num_clusters; i++) {
count++;
if (exfat_ent_get_safe(sb, clu, &clu))
return -EIO;
if (IS_CLUS_EOF(clu))
break;
}
*ret_count = count;
return 0;
}
/*
* Upcase table Management Functions
*/
static void free_upcase_table(struct super_block *sb)
{
u32 i;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
u16 **upcase_table;
upcase_table = fsi->vol_utbl;
for (i = 0 ; i < UTBL_COL_COUNT ; i++) {
/* kfree(NULL) is safe */
kfree(upcase_table[i]);
upcase_table[i] = NULL;
}
/* kfree(NULL) is safe */
kfree(fsi->vol_utbl);
fsi->vol_utbl = NULL;
}
static s32 __load_upcase_table(struct super_block *sb, u64 sector, u64 num_sectors, u32 utbl_checksum)
{
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
struct buffer_head *tmp_bh = NULL;
u32 sect_size = (u32)sb->s_blocksize;
s32 ret = -EIO;
u32 i, j;
u8 skip = false;
u32 index = 0;
u32 checksum = 0;
u16 **upcase_table = kzalloc((UTBL_COL_COUNT * sizeof(u16 *)), GFP_KERNEL);
if (!upcase_table)
return -ENOMEM;
/* thanks for kzalloc
* memset(upcase_table, 0, UTBL_COL_COUNT * sizeof(u16 *));
*/
fsi->vol_utbl = upcase_table;
num_sectors += sector;
while (sector < num_sectors) {
ret = exfat_read_sect(sb, sector, &tmp_bh, 1);
if (ret) {
EMSG("%s: failed to read sector(0x%llx)\n",
__func__, sector);
goto error;
}
sector++;
for (i = 0; i < sect_size && index <= 0xFFFF; i += 2) {
/* FIXME : is __le16 ok? */
//u16 uni = le16_to_cpu(((__le16*)(tmp_bh->b_data))[i]);
u16 uni = get_unaligned_le16((u8 *)tmp_bh->b_data+i);
checksum = ((checksum & 1) ? 0x80000000 : 0) +
(checksum >> 1) + *(((u8 *)tmp_bh->b_data)+i);
checksum = ((checksum & 1) ? 0x80000000 : 0) +
(checksum >> 1) + *(((u8 *)tmp_bh->b_data)+(i+1));
if (skip) {
MMSG("skip from 0x%X to 0x%X(amount of 0x%X)\n",
index, index+uni, uni);
index += uni;
skip = false;
} else if (uni == index) {
index++;
} else if (uni == 0xFFFF) {
skip = true;
} else { /* uni != index , uni != 0xFFFF */
u16 col_index = exfat_get_col_index(index);
if (!upcase_table[col_index]) {
upcase_table[col_index] =
kmalloc((UTBL_ROW_COUNT * sizeof(u16)), GFP_KERNEL);
if (!upcase_table[col_index]) {
EMSG("failed to allocate memory"
" for column 0x%X\n",
col_index);
ret = -ENOMEM;
goto error;
}
for (j = 0; j < UTBL_ROW_COUNT; j++)
upcase_table[col_index][j] = (col_index << LOW_INDEX_BIT) | j;
}
upcase_table[col_index][exfat_get_row_index(index)] = uni;
index++;
}
}
}
if (index >= 0xFFFF && utbl_checksum == checksum) {
DMSG("%s: load upcase table successfully"
"(idx:0x%08x, utbl_chksum:0x%08x)\n",
__func__, index, utbl_checksum);
if (tmp_bh)
brelse(tmp_bh);
return 0;
}
EMSG("%s: failed to load upcase table"
"(idx:0x%08x, chksum:0x%08x, utbl_chksum:0x%08x)\n",
__func__, index, checksum, utbl_checksum);
ret = -EINVAL;
error:
if (tmp_bh)
brelse(tmp_bh);
free_upcase_table(sb);
return ret;
}
static s32 __load_default_upcase_table(struct super_block *sb)
{
s32 i, ret = -EIO;
u32 j;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
u8 skip = false;
u32 index = 0;
u16 uni = 0;
u16 **upcase_table;
upcase_table = kmalloc((UTBL_COL_COUNT * sizeof(u16 *)), GFP_KERNEL);
if (!upcase_table)
return -ENOMEM;
fsi->vol_utbl = upcase_table;
memset(upcase_table, 0, UTBL_COL_COUNT * sizeof(u16 *));
for (i = 0; index <= 0xFFFF && i < EXFAT_NUM_UPCASE*2; i += 2) {
/* FIXME : is __le16 ok? */
//uni = le16_to_cpu(((__le16*)uni_def_upcase)[i>>1]);
uni = get_unaligned_le16((u8 *)uni_def_upcase+i);
if (skip) {
MMSG("skip from 0x%x ", index);
index += uni;
MMSG("to 0x%x (amount of 0x%x)\n", index, uni);
skip = false;
} else if (uni == index) {
index++;
} else if (uni == 0xFFFF) {
skip = true;
} else { /* uni != index , uni != 0xFFFF */
u16 col_index = exfat_get_col_index(index);
if (!upcase_table[col_index]) {
upcase_table[col_index] = kmalloc((UTBL_ROW_COUNT * sizeof(u16)), GFP_KERNEL);
if (!upcase_table[col_index]) {
EMSG("failed to allocate memory for "
"new column 0x%x\n", col_index);
ret = -ENOMEM;
goto error;
}
for (j = 0; j < UTBL_ROW_COUNT; j++)
upcase_table[col_index][j] = (col_index << LOW_INDEX_BIT) | j;
}
upcase_table[col_index][exfat_get_row_index(index)] = uni;
index++;
}
}
if (index >= 0xFFFF)
return 0;
error:
/* FATAL error: default upcase table has error */
free_upcase_table(sb);
return ret;
}
static s32 load_upcase_table(struct super_block *sb)
{
s32 i, ret;
u32 tbl_clu, type;
u64 sector, tbl_size, num_sectors;
u8 blksize_bits = sb->s_blocksize_bits;
CHAIN_T clu;
CASE_DENTRY_T *ep;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
clu.dir = fsi->root_dir;
clu.flags = 0x01;
while (!IS_CLUS_EOF(clu.dir)) {
for (i = 0; i < fsi->dentries_per_clu; i++) {
ep = (CASE_DENTRY_T *) exfat_get_dentry_in_dir(sb, &clu, i, NULL);
if (!ep)
return -EIO;
type = fsi->fs_func->get_entry_type((DENTRY_T *) ep);
if (type == TYPE_UNUSED)
break;
if (type != TYPE_UPCASE)
continue;
tbl_clu = le32_to_cpu(ep->start_clu);
tbl_size = le64_to_cpu(ep->size);
sector = CLUS_TO_SECT(fsi, tbl_clu);
num_sectors = ((tbl_size - 1) >> blksize_bits) + 1;
ret = __load_upcase_table(sb, sector, num_sectors,
le32_to_cpu(ep->checksum));
if (ret && (ret != -EIO))
goto load_default;
/* load successfully */
return ret;
}
if (get_next_clus_safe(sb, &(clu.dir)))
return -EIO;
}
load_default:
exfat_log_msg(sb, KERN_INFO, "trying to load default upcase table");
/* load default upcase table */
return __load_default_upcase_table(sb);
}
/*
* Directory Entry Management Functions
*/
s32 exfat_walk_fat_chain(struct super_block *sb, CHAIN_T *p_dir, u32 byte_offset, u32 *clu)
{
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
u32 clu_offset;
u32 cur_clu;
clu_offset = byte_offset >> fsi->cluster_size_bits;
cur_clu = p_dir->dir;
if (p_dir->flags == 0x03) {
cur_clu += clu_offset;
} else {
while (clu_offset > 0) {
if (get_next_clus_safe(sb, &cur_clu))
return -EIO;
if (IS_CLUS_EOF(cur_clu)) {
exfat_fs_error(sb, "invalid dentry access "
"beyond EOF (clu : %u, eidx : %d)",
p_dir->dir,
byte_offset >> DENTRY_SIZE_BITS);
return -EIO;
}
clu_offset--;
}
}
if (clu)
*clu = cur_clu;
return 0;
}
static s32 find_location(struct super_block *sb, CHAIN_T *p_dir, s32 entry, u64 *sector, s32 *offset)
{
s32 ret;
u32 off, clu = 0;
u32 blksize_mask = (u32)(sb->s_blocksize-1);
u8 blksize_bits = sb->s_blocksize_bits;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
off = entry << DENTRY_SIZE_BITS;
/* FAT16 root_dir */
if (IS_CLUS_FREE(p_dir->dir)) {
*offset = off & blksize_mask;
*sector = off >> blksize_bits;
*sector += fsi->root_start_sector;
return 0;
}
ret = exfat_walk_fat_chain(sb, p_dir, off, &clu);
if (ret)
return ret;
/* byte offset in cluster */
off &= (fsi->cluster_size - 1);
/* byte offset in sector */
*offset = off & blksize_mask;
/* sector offset in cluster */
*sector = off >> blksize_bits;
*sector += CLUS_TO_SECT(fsi, clu);
return 0;
}
DENTRY_T *exfat_get_dentry_in_dir(struct super_block *sb, CHAIN_T *p_dir, s32 entry, u64 *sector)
{
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
u32 dentries_per_page = PAGE_SIZE >> DENTRY_SIZE_BITS;
s32 off;
u64 sec;
u8 *buf;
if (p_dir->dir == DIR_DELETED) {
EMSG("%s : abnormal access to deleted dentry\n", __func__);
BUG_ON(!fsi->prev_eio);
return NULL;
}
if (find_location(sb, p_dir, entry, &sec, &off))
return NULL;
/* DIRECTORY READAHEAD :
* Try to read ahead per a page except root directory of fat12/16
*/
if ((!IS_CLUS_FREE(p_dir->dir)) &&
!(entry & (dentries_per_page - 1)))
exfat_dcache_readahead(sb, sec);
buf = exfat_dcache_getblk(sb, sec);
if (!buf)
return NULL;
if (sector)
*sector = sec;
return (DENTRY_T *)(buf + off);
}
/* used only in search empty_slot() */
#define CNT_UNUSED_NOHIT (-1)
#define CNT_UNUSED_HIT (-2)
/* search EMPTY CONTINUOUS "num_entries" entries */
static s32 search_empty_slot(struct super_block *sb, HINT_FEMP_T *hint_femp, CHAIN_T *p_dir, s32 num_entries)
{
s32 i, dentry, num_empty = 0;
s32 dentries_per_clu;
u32 type;
CHAIN_T clu;
DENTRY_T *ep;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
if (IS_CLUS_FREE(p_dir->dir)) /* FAT16 root_dir */
dentries_per_clu = fsi->dentries_in_root;
else
dentries_per_clu = fsi->dentries_per_clu;
ASSERT(-1 <= hint_femp->eidx);
if (hint_femp->eidx != -1) {
clu.dir = hint_femp->cur.dir;
clu.size = hint_femp->cur.size;
clu.flags = hint_femp->cur.flags;
dentry = hint_femp->eidx;
if (num_entries <= hint_femp->count) {
MMSG("%s: empty slot(HIT) - found "
"(clu : 0x%08x eidx : %d)\n",
__func__, hint_femp->cur.dir, hint_femp->eidx);
hint_femp->eidx = -1;
return dentry;
}
MMSG("%s: empty slot(HIT) - search from "
"(clu : 0x%08x eidx : %d)\n",
__func__, hint_femp->cur.dir, hint_femp->eidx);
} else {
MMSG("%s: empty slot(MISS) - search from "
"(clu:0x%08x eidx : 0)\n",
__func__, p_dir->dir);
clu.dir = p_dir->dir;
clu.size = p_dir->size;
clu.flags = p_dir->flags;
dentry = 0;
}
while (!IS_CLUS_EOF(clu.dir)) {
/* FAT16 root_dir */
if (IS_CLUS_FREE(p_dir->dir))
i = dentry % dentries_per_clu;
else
i = dentry & (dentries_per_clu-1);
for ( ; i < dentries_per_clu; i++, dentry++) {
ep = exfat_get_dentry_in_dir(sb, &clu, i, NULL);
if (!ep)
return -EIO;
type = fsi->fs_func->get_entry_type(ep);
if ((type == TYPE_UNUSED) || (type == TYPE_DELETED)) {
num_empty++;
if (hint_femp->eidx == -1) {
hint_femp->eidx = dentry;
hint_femp->count = CNT_UNUSED_NOHIT;
hint_femp->cur.dir = clu.dir;
hint_femp->cur.size = clu.size;
hint_femp->cur.flags = clu.flags;
}
if ((type == TYPE_UNUSED) &&
(hint_femp->count != CNT_UNUSED_HIT)) {
hint_femp->count = CNT_UNUSED_HIT;
}
} else {
if ((hint_femp->eidx != -1) &&
(hint_femp->count == CNT_UNUSED_HIT)) {
/* unused empty group means
* an empty group which includes
* unused dentry
*/
exfat_fs_error(sb,
"found bogus dentry(%d) "
"beyond unused empty group(%d) "
"(start_clu : %u, cur_clu : %u)",
dentry, hint_femp->eidx, p_dir->dir,
clu.dir);
return -EIO;
}
num_empty = 0;
hint_femp->eidx = -1;
}
if (num_empty >= num_entries) {
/* found and invalidate hint_femp */
hint_femp->eidx = -1;
return (dentry - (num_entries-1));
}
}
if (IS_CLUS_FREE(p_dir->dir))
break; /* FAT16 root_dir */
if (clu.flags == 0x03) {
if ((--clu.size) > 0)
clu.dir++;
else
clu.dir = CLUS_EOF;
} else {
if (get_next_clus_safe(sb, &(clu.dir)))
return -EIO;
}
}
return -ENOSPC;
}
/*
* find empty directory entry.
* if there isn't any empty slot, expand cluster chain.
*/
static s32 find_empty_entry(struct inode *inode, CHAIN_T *p_dir, s32 num_entries)
{
s32 dentry;
u32 ret, last_clu;
u64 sector;
u64 size = 0;
CHAIN_T clu;
DENTRY_T *ep = NULL;
struct super_block *sb = inode->i_sb;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
FILE_ID_T *fid = &(EXFAT_I(inode)->fid);
HINT_FEMP_T hint_femp;
hint_femp.eidx = -1;
ASSERT(-1 <= fid->hint_femp.eidx);
if (fid->hint_femp.eidx != -1) {
memcpy(&hint_femp, &fid->hint_femp, sizeof(HINT_FEMP_T));
fid->hint_femp.eidx = -1;
}
/* FAT16 root_dir */
if (IS_CLUS_FREE(p_dir->dir))
return search_empty_slot(sb, &hint_femp, p_dir, num_entries);
while ((dentry = search_empty_slot(sb, &hint_femp, p_dir, num_entries)) < 0) {
if (dentry == -EIO)
break;
if (fsi->fs_func->check_max_dentries(fid))
return -ENOSPC;
/* we trust p_dir->size regardless of FAT type */
if (__find_last_cluster(sb, p_dir, &last_clu))
return -EIO;
/*
* Allocate new cluster to this directory
*/
clu.dir = last_clu + 1;
clu.size = 0; /* UNUSED */
clu.flags = p_dir->flags;
/* (0) check if there are reserved clusters
* Refer to create_dir's comments
*/
if (!IS_CLUS_EOF(fsi->used_clusters) &&
((fsi->used_clusters + fsi->reserved_clusters) >= (fsi->num_clusters - 2)))
return -ENOSPC;
/* (1) allocate a cluster */
ret = fsi->fs_func->alloc_cluster(sb, 1, &clu, ALLOC_HOT);
if (ret)
return ret;
if (__clear_cluster(inode, clu.dir))
return -EIO;
/* (2) append to the FAT chain */
if (clu.flags != p_dir->flags) {
/* no-fat-chain bit is disabled,
* so fat-chain should be synced with alloc-bmp
*/
exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
p_dir->flags = 0x01;
hint_femp.cur.flags = 0x01;
}
if (clu.flags == 0x01)
if (exfat_ent_set(sb, last_clu, clu.dir))
return -EIO;
if (hint_femp.eidx == -1) {
/* the special case that new dentry
* should be allocated from the start of new cluster
*/
hint_femp.eidx = (s32)(p_dir->size <<
(fsi->cluster_size_bits - DENTRY_SIZE_BITS));
hint_femp.count = fsi->dentries_per_clu;
hint_femp.cur.dir = clu.dir;
hint_femp.cur.size = 0;
hint_femp.cur.flags = clu.flags;
}
hint_femp.cur.size++;
p_dir->size++;
size = (p_dir->size << fsi->cluster_size_bits);
/* (3) update the directory entry */
if (p_dir->dir != fsi->root_dir) {
ep = exfat_get_dentry_in_dir(sb,
&(fid->dir), fid->entry+1, §or);
if (!ep)
return -EIO;
fsi->fs_func->set_entry_size(ep, size);
fsi->fs_func->set_entry_flag(ep, p_dir->flags);
if (exfat_dcache_modify(sb, sector))
return -EIO;
if (exfat_update_dir_chksum(sb, &(fid->dir), fid->entry))
return -EIO;
}
/* directory inode should be updated in here */
i_size_write(inode, (loff_t)size);
EXFAT_I(inode)->i_size_ondisk += fsi->cluster_size;
EXFAT_I(inode)->i_size_aligned += fsi->cluster_size;
EXFAT_I(inode)->fid.size = size;
EXFAT_I(inode)->fid.flags = p_dir->flags;
inode->i_blocks += 1 << (fsi->cluster_size_bits - sb->s_blocksize_bits);
}
return dentry;
}
#define EXFAT_MIN_SUBDIR (2)
static s32 __count_dos_name_entries(struct super_block *sb, CHAIN_T *p_dir, u32 type, u32 *dotcnt)
{
s32 i, count = 0, check_dot = 0;
s32 dentries_per_clu;
u32 entry_type;
CHAIN_T clu;
DENTRY_T *ep;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
if (IS_CLUS_FREE(p_dir->dir)) /* FAT16 root_dir */
dentries_per_clu = fsi->dentries_in_root;
else
dentries_per_clu = fsi->dentries_per_clu;
clu.dir = p_dir->dir;
clu.size = p_dir->size;
clu.flags = p_dir->flags;
if (dotcnt)
*dotcnt = 0;
while (!IS_CLUS_EOF(clu.dir)) {
for (i = 0; i < dentries_per_clu; i++) {
ep = exfat_get_dentry_in_dir(sb, &clu, i, NULL);
if (!ep)
return -EIO;
entry_type = fsi->fs_func->get_entry_type(ep);
if (entry_type == TYPE_UNUSED)
return count;
if (!(type & TYPE_CRITICAL_PRI) && !(type & TYPE_BENIGN_PRI))
continue;
if ((type != TYPE_ALL) && (type != entry_type))
continue;
count++;
}
/* FAT16 root_dir */
if (IS_CLUS_FREE(p_dir->dir))
break;
if (clu.flags == 0x03) {
if ((--clu.size) > 0)
clu.dir++;
else
clu.dir = CLUS_EOF;
} else {
if (get_next_clus_safe(sb, &(clu.dir)))
return -EIO;
}
check_dot = 0;
}
return count;
}
s32 check_dir_empty(struct super_block *sb, CHAIN_T *p_dir)
{
s32 i;
s32 dentries_per_clu;
u32 type;
CHAIN_T clu;
DENTRY_T *ep;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
if (IS_CLUS_FREE(p_dir->dir)) /* FAT16 root_dir */
dentries_per_clu = fsi->dentries_in_root;
else
dentries_per_clu = fsi->dentries_per_clu;
clu.dir = p_dir->dir;
clu.size = p_dir->size;
clu.flags = p_dir->flags;
while (!IS_CLUS_EOF(clu.dir)) {
for (i = 0; i < dentries_per_clu; i++) {
ep = exfat_get_dentry_in_dir(sb, &clu, i, NULL);
if (!ep)
return -EIO;
type = fsi->fs_func->get_entry_type(ep);
if (type == TYPE_UNUSED)
return 0;
if ((type != TYPE_FILE) && (type != TYPE_DIR))
continue;
return -ENOTEMPTY;
}
/* FAT16 root_dir */
if (IS_CLUS_FREE(p_dir->dir))
return -ENOTEMPTY;
if (clu.flags == 0x03) {
if ((--clu.size) > 0)
clu.dir++;
else
clu.dir = CLUS_EOF;
} else {
if (get_next_clus_safe(sb, &(clu.dir)))
return -EIO;
}
}
return 0;
}
/* input : dir, uni_name
* output : num_of_entry, dos_name(format : aaaaaa~1.bbb)
*/
static s32 get_num_entries_and_dos_name(struct super_block *sb, CHAIN_T *p_dir,
UNI_NAME_T *p_uniname, s32 *entries,
DOS_NAME_T *p_dosname, s32 lookup)
{
s32 num_entries;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
/* Init null char. */
p_dosname->name[0] = '\0';
num_entries = fsi->fs_func->calc_num_entries(p_uniname);
if (num_entries == 0)
return -EINVAL;
*entries = num_entries;
return 0;
}
void exfat_get_uniname_from_dos_entry(struct super_block *sb, DOS_DENTRY_T *ep, UNI_NAME_T *p_uniname, u8 mode)
{
DOS_NAME_T dos_name;
if (mode == 0x0)
dos_name.name_case = 0x0;
else
dos_name.name_case = ep->lcase;
memcpy(dos_name.name, ep->name, DOS_NAME_LENGTH);
exfat_nls_sfn_to_uni16s(sb, &dos_name, p_uniname);
}
/* returns the length of a struct qstr, ignoring trailing dots */
static inline unsigned int __striptail_len(unsigned int len, const char *name)
{
while (len && name[len - 1] == '.')
len--;
return len;
}
/*
* Name Resolution Functions :
* Zero if it was successful; otherwise nonzero.
*/
static s32 __resolve_path(struct inode *inode, const u8 *path, CHAIN_T *p_dir, UNI_NAME_T *p_uniname, int lookup)
{
s32 namelen;
s32 lossy = NLS_NAME_NO_LOSSY;
struct super_block *sb = inode->i_sb;
FS_INFO_T *fsi = &(EXFAT_SB(sb)->fsi);
FILE_ID_T *fid = &(EXFAT_I(inode)->fid);
/* DOT and DOTDOT are handled by VFS layer */
/* strip all trailing spaces */
/* DO NOTHING : Is needed? */
/* strip all trailing periods */
namelen = __striptail_len(strlen(path), path);
if (!namelen)