| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1397322161-32148-3-git-send-email-tytso@mit.edu>
Date: Sat, 12 Apr 2014 13:02:38 -0400
From: Theodore Ts'o <tytso@....edu>
To: Ext4 Developers List <linux-ext4@...r.kernel.org>
Cc: viro@...IV.linux.org.uk, Theodore Ts'o <tytso@....edu>
Subject: [PATCH 2/5] ext4: move ext4_file_dio_write() into ext4_file_write()
This commit doesn't actually change anything; it just moves code
around in preparation for some code simplification work.
Signed-off-by: "Theodore Ts'o" <tytso@....edu>
---
fs/ext4/file.c | 139 +++++++++++++++++++++++++++------------------------------
1 file changed, 65 insertions(+), 74 deletions(-)
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 8b22556..3ec0c09 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -92,82 +92,15 @@ ext4_unaligned_aio(struct inode *inode, const struct iovec *iov,
}
static ssize_t
-ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t pos)
+ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
{
struct file *file = iocb->ki_filp;
- struct inode *inode = file->f_mapping->host;
+ struct inode *inode = file_inode(iocb->ki_filp);
struct blk_plug plug;
int unaligned_aio = 0;
- ssize_t ret;
int overwrite = 0;
size_t length = iov_length(iov, nr_segs);
-
- if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
- !is_sync_kiocb(iocb))
- unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos);
-
- /* Unaligned direct AIO must be serialized; see comment above */
- if (unaligned_aio) {
- mutex_lock(ext4_aio_mutex(inode));
- ext4_unwritten_wait(inode);
- }
-
- mutex_lock(&inode->i_mutex);
- blk_start_plug(&plug);
-
- iocb->private = &overwrite;
-
- /* check whether we do a DIO overwrite or not */
- if (ext4_should_dioread_nolock(inode) && !unaligned_aio &&
- !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
- struct ext4_map_blocks map;
- unsigned int blkbits = inode->i_blkbits;
- int err, len;
-
- map.m_lblk = pos >> blkbits;
- map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
- - map.m_lblk;
- len = map.m_len;
-
- err = ext4_map_blocks(NULL, inode, &map, 0);
- /*
- * 'err==len' means that all of blocks has been preallocated no
- * matter they are initialized or not. For excluding
- * unwritten extents, we need to check m_flags. There are
- * two conditions that indicate for initialized extents.
- * 1) If we hit extent cache, EXT4_MAP_MAPPED flag is returned;
- * 2) If we do a real lookup, non-flags are returned.
- * So we should check these two conditions.
- */
- if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
- overwrite = 1;
- }
-
- ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
- mutex_unlock(&inode->i_mutex);
-
- if (ret > 0) {
- ssize_t err;
-
- err = generic_write_sync(file, iocb->ki_pos - ret, ret);
- if (err < 0)
- ret = err;
- }
- blk_finish_plug(&plug);
-
- if (unaligned_aio)
- mutex_unlock(ext4_aio_mutex(inode));
-
- return ret;
-}
-
-static ssize_t
-ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t pos)
-{
- struct file *file = iocb->ki_filp;
- struct inode *inode = file_inode(iocb->ki_filp);
ssize_t ret;
BUG_ON(iocb->ki_pos != pos);
@@ -179,7 +112,6 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
- size_t length = iov_length(iov, nr_segs);
if ((pos > sbi->s_bitmap_maxbytes ||
(pos == sbi->s_bitmap_maxbytes && length > 0)))
@@ -191,9 +123,68 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
}
}
- if (unlikely(iocb->ki_filp->f_flags & O_DIRECT))
- ret = ext4_file_dio_write(iocb, iov, nr_segs, pos);
- else {
+ if (unlikely(iocb->ki_filp->f_flags & O_DIRECT)) {
+ if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
+ !is_sync_kiocb(iocb))
+ unaligned_aio = ext4_unaligned_aio(inode, iov,
+ nr_segs, pos);
+
+ /* Unaligned direct AIO must be serialized; see comment above */
+ if (unaligned_aio) {
+ mutex_lock(ext4_aio_mutex(inode));
+ ext4_unwritten_wait(inode);
+ }
+
+ mutex_lock(&inode->i_mutex);
+ blk_start_plug(&plug);
+
+ iocb->private = &overwrite;
+
+ /* check whether we do a DIO overwrite or not */
+ if (ext4_should_dioread_nolock(inode) && !unaligned_aio &&
+ !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
+ struct ext4_map_blocks map;
+ unsigned int blkbits = inode->i_blkbits;
+ int err, len;
+
+ map.m_lblk = pos >> blkbits;
+ map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
+ - map.m_lblk;
+ len = map.m_len;
+
+ err = ext4_map_blocks(NULL, inode, &map, 0);
+ /*
+ * 'err==len' means that all of blocks has
+ * been preallocated no matter they are
+ * initialized or not. For excluding
+ * unwritten extents, we need to check
+ * m_flags. There are two conditions that
+ * indicate for initialized extents. 1) If we
+ * hit extent cache, EXT4_MAP_MAPPED flag is
+ * returned; 2) If we do a real lookup,
+ * non-flags are returned. So we should check
+ * these two conditions.
+ */
+ if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
+ overwrite = 1;
+ }
+
+ ret = __generic_file_aio_write(iocb, iov, nr_segs,
+ &iocb->ki_pos);
+ mutex_unlock(&inode->i_mutex);
+
+ if (ret > 0) {
+ ssize_t err;
+
+ err = generic_write_sync(file, iocb->ki_pos - ret, ret);
+ if (err < 0)
+ ret = err;
+ }
+ blk_finish_plug(&plug);
+
+ if (unaligned_aio)
+ mutex_unlock(ext4_aio_mutex(inode));
+ } else {
mutex_lock(&inode->i_mutex);
ret = __generic_file_aio_write(iocb, iov, nr_segs,
&iocb->ki_pos);
--
1.9.0
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists