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ext4: create __ext4_insert_dentry for dir entry insertion
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The old add_dirent_to_buf handles all the work related to the
work of adding dir entry to a dir block. Now we have inline data,
so create 2 new function __ext4_find_dest_de and __ext4_insert_dentry
that do the real work and let add_dirent_to_buf call them.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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Tao Ma authored and Theodore Ts'o committed Dec 10, 2012
1 parent 226ba97 commit 978fef9
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Showing 2 changed files with 80 additions and 40 deletions.
15 changes: 15 additions & 0 deletions fs/ext4/ext4.h
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Original file line number Diff line number Diff line change
Expand Up @@ -1969,6 +1969,21 @@ extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
__u32 minor_hash,
struct ext4_dir_entry_2 *dirent);
extern void ext4_htree_free_dir_info(struct dir_private_info *p);
extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
struct buffer_head *bh,
void *buf, int buf_size,
const char *name, int namelen,
struct ext4_dir_entry_2 **dest_de);
void ext4_insert_dentry(struct inode *inode,
struct ext4_dir_entry_2 *de,
int buf_size,
const char *name, int namelen);
static inline void ext4_update_dx_flag(struct inode *inode)
{
if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
EXT4_FEATURE_COMPAT_DIR_INDEX))
ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
}

/* fsync.c */
extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
Expand Down
105 changes: 65 additions & 40 deletions fs/ext4/namei.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1084,13 +1084,6 @@ static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
dx_set_count(entries, count + 1);
}

static void ext4_update_dx_flag(struct inode *inode)
{
if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
EXT4_FEATURE_COMPAT_DIR_INDEX))
ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
}

/*
* NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure.
*
Expand Down Expand Up @@ -1614,6 +1607,63 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
return NULL;
}

int ext4_find_dest_de(struct inode *dir, struct inode *inode,
struct buffer_head *bh,
void *buf, int buf_size,
const char *name, int namelen,
struct ext4_dir_entry_2 **dest_de)
{
struct ext4_dir_entry_2 *de;
unsigned short reclen = EXT4_DIR_REC_LEN(namelen);
int nlen, rlen;
unsigned int offset = 0;
char *top;

de = (struct ext4_dir_entry_2 *)buf;
top = buf + buf_size - reclen;
while ((char *) de <= top) {
if (ext4_check_dir_entry(dir, NULL, de, bh,
buf, buf_size, offset))
return -EIO;
if (ext4_match(namelen, name, de))
return -EEXIST;
nlen = EXT4_DIR_REC_LEN(de->name_len);
rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
if ((de->inode ? rlen - nlen : rlen) >= reclen)
break;
de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
offset += rlen;
}
if ((char *) de > top)
return -ENOSPC;

*dest_de = de;
return 0;
}

void ext4_insert_dentry(struct inode *inode,
struct ext4_dir_entry_2 *de,
int buf_size,
const char *name, int namelen)
{

int nlen, rlen;

nlen = EXT4_DIR_REC_LEN(de->name_len);
rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
if (de->inode) {
struct ext4_dir_entry_2 *de1 =
(struct ext4_dir_entry_2 *)((char *)de + nlen);
de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
de = de1;
}
de->file_type = EXT4_FT_UNKNOWN;
de->inode = cpu_to_le32(inode->i_ino);
ext4_set_de_type(inode->i_sb, de, inode->i_mode);
de->name_len = namelen;
memcpy(de->name, name, namelen);
}
/*
* Add a new entry into a directory (leaf) block. If de is non-NULL,
* it points to a directory entry which is guaranteed to be large
Expand All @@ -1629,36 +1679,22 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
struct inode *dir = dentry->d_parent->d_inode;
const char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
unsigned int offset = 0;
unsigned int blocksize = dir->i_sb->s_blocksize;
unsigned short reclen;
int nlen, rlen, err;
char *top;
int csum_size = 0;
int err;

if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
csum_size = sizeof(struct ext4_dir_entry_tail);

reclen = EXT4_DIR_REC_LEN(namelen);
if (!de) {
de = (struct ext4_dir_entry_2 *)bh->b_data;
top = bh->b_data + (blocksize - csum_size) - reclen;
while ((char *) de <= top) {
if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
bh->b_size, offset))
return -EIO;
if (ext4_match(namelen, name, de))
return -EEXIST;
nlen = EXT4_DIR_REC_LEN(de->name_len);
rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
if ((de->inode? rlen - nlen: rlen) >= reclen)
break;
de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
offset += rlen;
}
if ((char *) de > top)
return -ENOSPC;
err = ext4_find_dest_de(dir, inode,
bh, bh->b_data, blocksize - csum_size,
name, namelen, &de);
if (err)
return err;
}
BUFFER_TRACE(bh, "get_write_access");
err = ext4_journal_get_write_access(handle, bh);
Expand All @@ -1668,19 +1704,8 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
}

/* By now the buffer is marked for journaling */
nlen = EXT4_DIR_REC_LEN(de->name_len);
rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
if (de->inode) {
struct ext4_dir_entry_2 *de1 = (struct ext4_dir_entry_2 *)((char *)de + nlen);
de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, blocksize);
de->rec_len = ext4_rec_len_to_disk(nlen, blocksize);
de = de1;
}
de->file_type = EXT4_FT_UNKNOWN;
de->inode = cpu_to_le32(inode->i_ino);
ext4_set_de_type(dir->i_sb, de, inode->i_mode);
de->name_len = namelen;
memcpy(de->name, name, namelen);
ext4_insert_dentry(inode, de, blocksize, name, namelen);

/*
* XXX shouldn't update any times until successful
* completion of syscall, but too many callers depend
Expand Down

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