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Message-Id: <1319614468-11227-9-git-send-email-tm@tao.ma>
Date: Wed, 26 Oct 2011 15:34:20 +0800
From: Tao Ma <tm@....ma>
To: linux-ext4@...r.kernel.org
Cc: tytso@....edu, linux-kernel@...r.kernel.org, adilger@...ger.ca
Subject: [PATCH V1 09/17] ext4: Create __ext4_insert_dentry for dir entry insertion.
From: Tao Ma <boyu.mt@...bao.com>
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@...bao.com>
---
fs/ext4/namei.c | 104 ++++++++++++++++++++++++++++++++++++-------------------
1 files changed, 68 insertions(+), 36 deletions(-)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index d7661cb..2e83b92 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1243,6 +1243,66 @@ errout:
return NULL;
}
+static inline 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;
+}
+
+static inline 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;
+ if (inode) {
+ de->inode = cpu_to_le32(inode->i_ino);
+ ext4_set_de_type(inode->i_sb, de, inode->i_mode);
+ } else
+ de->inode = 0;
+ 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
@@ -1258,31 +1318,17 @@ 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 err;
reclen = EXT4_DIR_REC_LEN(namelen);
if (!de) {
- de = (struct ext4_dir_entry_2 *)bh->b_data;
- top = bh->b_data + blocksize - 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,
+ name, namelen, &de);
+ if (err)
+ return err;
}
BUFFER_TRACE(bh, "get_write_access");
err = ext4_journal_get_write_access(handle, bh);
@@ -1292,22 +1338,8 @@ 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;
- if (inode) {
- de->inode = cpu_to_le32(inode->i_ino);
- ext4_set_de_type(dir->i_sb, de, inode->i_mode);
- } else
- de->inode = 0;
- 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
--
1.7.0.4
--
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