From: Tao Ma Subject: [PATCH V3 12/21] ext4: Let ext4_readdir handle inline data. Date: Sun, 18 Dec 2011 22:24:29 +0800 Message-ID: <1324218278-2460-12-git-send-email-tm@tao.ma> References: <4EEDF6B1.7050206@tao.ma> <1324218278-2460-1-git-send-email-tm@tao.ma> Cc: adilger@dilger.ca, tytso@mit.edu, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org To: linux-ext4@vger.kernel.org Return-path: In-Reply-To: <1324218278-2460-1-git-send-email-tm@tao.ma> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org From: Tao Ma Signed-off-by: Tao Ma --- fs/ext4/dir.c | 23 ++++------ fs/ext4/ext4.h | 12 +++++ fs/ext4/inline.c | 124 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/ext4/xattr.h | 7 +++ 4 files changed, 153 insertions(+), 13 deletions(-) diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index 6c2199e..691548c 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -27,10 +27,7 @@ #include #include #include "ext4.h" - -static unsigned char ext4_filetype_table[] = { - DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK -}; +#include "xattr.h" static int ext4_readdir(struct file *, void *, filldir_t); static int ext4_dx_readdir(struct file *filp, @@ -51,19 +48,13 @@ const struct file_operations ext4_dir_operations = { }; -static unsigned char get_dtype(struct super_block *sb, int filetype) -{ - if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) || - (filetype >= EXT4_FT_MAX)) - return DT_UNKNOWN; - - return (ext4_filetype_table[filetype]); -} - /* * Return 0 if the directory entry is OK, and 1 if there is a problem * * Note: this is the opposite of what ext2 and ext3 historically returned... + * + * bh passed here can be an inode block or a dir data block, depending + * on the inode inline data flag. */ int __ext4_check_dir_entry(const char *function, unsigned int line, struct inode *dir, struct file *filp, @@ -122,6 +113,12 @@ static int ext4_readdir(struct file *filp, sb = inode->i_sb; + if (ext4_has_inline_data(inode)) { + ret = ext4_read_inline_dir(filp, dirent, filldir); + if (ret > 0 || ret < 0) + return ret; + } + if (EXT4_HAS_COMPAT_FEATURE(inode->i_sb, EXT4_FEATURE_COMPAT_DIR_INDEX) && ((ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) || diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index e61c967..25d6e58 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1832,6 +1832,18 @@ static inline void ext4_update_dx_flag(struct inode *inode) EXT4_FEATURE_COMPAT_DIR_INDEX)) ext4_clear_inode_flag(inode, EXT4_INODE_INDEX); } +static unsigned char ext4_filetype_table[] = { + DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK +}; + +static inline unsigned char get_dtype(struct super_block *sb, int filetype) +{ + if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) || + (filetype >= EXT4_FT_MAX)) + return DT_UNKNOWN; + + return ext4_filetype_table[filetype]; +} /* fsync.c */ extern int ext4_sync_file(struct file *, loff_t, loff_t, int); diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index db70d3e..0a41d64 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -1176,6 +1176,130 @@ out: } /* + * Get the inline dentry at offset. + */ +static inline struct ext4_dir_entry_2 * +ext4_get_inline_entry(struct inode *inode, + struct ext4_iloc *iloc, + unsigned int offset, + void **inline_start, + int *inline_size) +{ + void *inline_pos; + + BUG_ON(offset > ext4_get_inline_size(inode)); + + if (offset < EXT4_MIN_INLINE_DATA_SIZE) { + inline_pos = ext4_raw_inode(iloc)->i_block; + *inline_size = EXT4_MIN_INLINE_DATA_SIZE; + } else { + inline_pos = ext4_get_inline_xattr_pos(inode, iloc); + offset -= EXT4_MIN_INLINE_DATA_SIZE; + *inline_size = ext4_get_inline_size(inode) - + EXT4_MIN_INLINE_DATA_SIZE; + } + + if (inline_start) + *inline_start = inline_pos; + return (struct ext4_dir_entry_2 *)(inline_pos + offset); +} + +int ext4_read_inline_dir(struct file *filp, + void *dirent, filldir_t filldir) +{ + int error = 0; + unsigned int offset; + int i, stored; + void *inline_pos; + struct ext4_dir_entry_2 *de; + struct super_block *sb; + struct inode *inode = filp->f_path.dentry->d_inode; + int ret, inline_size = 0; + struct ext4_iloc iloc; + + ret = ext4_get_inode_loc(inode, &iloc); + if (ret) + return ret; + + down_read(&EXT4_I(inode)->xattr_sem); + if (!ext4_has_inline_data(inode)) + goto out; + + sb = inode->i_sb; + stored = 0; + offset = filp->f_pos & (sb->s_blocksize - 1); + + while (!error && !stored && filp->f_pos < inode->i_size) { +revalidate: + /* If the version has changed since the last call to + * readdir(2), then we might be pointing to an invalid + * dirent right now. Scan from the start of the block + * to make sure. */ + if (filp->f_version != inode->i_version) { + for (i = 0; i < inode->i_size && i < offset; ) { + de = ext4_get_inline_entry(inode, &iloc, i, + NULL, &inline_size); + /* It's too expensive to do a full + * dirent test each time round this + * loop, but we do have to test at + * least that it is non-zero. A + * failure will be detected in the + * dirent test below. */ + if (ext4_rec_len_from_disk(de->rec_len, + inline_size) < EXT4_DIR_REC_LEN(1)) + break; + i += ext4_rec_len_from_disk(de->rec_len, + inline_size); + } + offset = i; + filp->f_pos = offset; + filp->f_version = inode->i_version; + } + + while (!error && filp->f_pos < inode->i_size) { + de = ext4_get_inline_entry(inode, &iloc, offset, + &inline_pos, &inline_size); + if (ext4_check_dir_entry(inode, filp, de, + iloc.bh, inline_pos, + inline_size, offset)) { + ret = stored; + goto out; + } + offset += ext4_rec_len_from_disk(de->rec_len, + inline_size); + if (le32_to_cpu(de->inode)) { + /* We might block in the next section + * if the data destination is + * currently swapped out. So, use a + * version stamp to detect whether or + * not the directory has been modified + * during the copy operation. + */ + u64 version = filp->f_version; + + error = filldir(dirent, de->name, + de->name_len, + filp->f_pos, + le32_to_cpu(de->inode), + get_dtype(sb, de->file_type)); + if (error) + break; + if (version != filp->f_version) + goto revalidate; + stored++; + } + filp->f_pos += ext4_rec_len_from_disk(de->rec_len, + inline_size); + } + offset = 0; + } +out: + up_read(&EXT4_I(inode)->xattr_sem); + brelse(iloc.bh); + return ret; +} + +/* * Try to create the inline data for the new dir. * If it succeeds, return 0, otherwise return the error. * In case of ENOSPC, the caller should create the normal disk layout dir. diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h index 0229a78..e9e23ba 100644 --- a/fs/ext4/xattr.h +++ b/fs/ext4/xattr.h @@ -166,6 +166,8 @@ extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry, extern int ext4_try_create_inline_dir(handle_t *handle, struct inode *parent, struct inode *inode); +extern int ext4_read_inline_dir(struct file *filp, + void *dirent, filldir_t filldir); # else /* CONFIG_EXT4_FS_XATTR */ static inline int @@ -343,6 +345,11 @@ static inline int ext4_try_create_inline_dir(handle_t *handle, { return 0; } +static inline int ext4_read_inline_dir(struct file *filp, + void *dirent, filldir_t filldir) +{ + return 0; +} # endif /* CONFIG_EXT4_FS_XATTR */ #ifdef CONFIG_EXT4_FS_SECURITY -- 1.7.0.4