From: zohar@linux.vnet.ibm.com (Mimi Zohar)
To: linux-security-module@vger.kernel.org
Subject: [RFC PATCH 3/3] fs: detect that the i_rwsem has already been taken exclusively
Date: Thu, 28 Sep 2017 08:39:33 -0400 [thread overview]
Message-ID: <1506602373-4799-4-git-send-email-zohar@linux.vnet.ibm.com> (raw)
In-Reply-To: <1506602373-4799-1-git-send-email-zohar@linux.vnet.ibm.com>
Don't attempt to take the i_rwsem, if it has already been taken
exclusively.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
---
fs/ext2/file.c | 6 ++++--
fs/ext4/file.c | 8 +++++---
fs/xfs/xfs_file.c | 10 ++++++----
3 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index 839095f66d8d..d174b2880929 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -38,9 +38,11 @@ static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to,
if (!iov_iter_count(to))
return 0; /* skip atime */
- inode_lock_shared(inode);
+ if (!rwf)
+ inode_lock_shared(inode);
ret = dax_iomap_rw(iocb, to, &ext2_iomap_ops);
- inode_unlock_shared(inode);
+ if (!rwf)
+ inode_unlock_shared(inode);
file_accessed(iocb->ki_filp);
return ret;
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 10789666725e..7d7c0e380add 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -38,7 +38,7 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to,
struct inode *inode = file_inode(iocb->ki_filp);
ssize_t ret;
- if (!inode_trylock_shared(inode)) {
+ if (!rwf && !inode_trylock_shared(inode)) {
if (iocb->ki_flags & IOCB_NOWAIT)
return -EAGAIN;
inode_lock_shared(inode);
@@ -48,12 +48,14 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to,
* change anymore
*/
if (!IS_DAX(inode)) {
- inode_unlock_shared(inode);
+ if (!rwf)
+ inode_unlock_shared(inode);
/* Fallback to buffered IO in case we cannot support DAX */
return generic_file_read_iter(iocb, to, rwf);
}
ret = dax_iomap_rw(iocb, to, &ext4_iomap_ops);
- inode_unlock_shared(inode);
+ if (!rwf)
+ inode_unlock_shared(inode);
file_accessed(iocb->ki_filp);
return ret;
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index cf1ce8961601..0cffca97ed68 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -239,7 +239,7 @@ xfs_file_dax_read(
if (!count)
return 0; /* skip atime */
- if (!xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED)) {
+ if (!rwf && !xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED)) {
if (iocb->ki_flags & IOCB_NOWAIT)
return -EAGAIN;
xfs_ilock(ip, XFS_IOLOCK_SHARED);
@@ -247,7 +247,8 @@ xfs_file_dax_read(
ret = dax_iomap_rw(iocb, to, &xfs_iomap_ops);
xfs_iunlock(ip, XFS_IOLOCK_SHARED);
- file_accessed(iocb->ki_filp);
+ if (!rwf)
+ file_accessed(iocb->ki_filp);
return ret;
}
@@ -262,13 +263,14 @@ xfs_file_buffered_aio_read(
trace_xfs_file_buffered_read(ip, iov_iter_count(to), iocb->ki_pos);
- if (!xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED)) {
+ if (!rwf && !xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED)) {
if (iocb->ki_flags & IOCB_NOWAIT)
return -EAGAIN;
xfs_ilock(ip, XFS_IOLOCK_SHARED);
}
ret = generic_file_read_iter(iocb, to, rwf);
- xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+ if (!rwf)
+ xfs_iunlock(ip, XFS_IOLOCK_SHARED);
return ret;
}
--
2.7.4
--
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next prev parent reply other threads:[~2017-09-28 12:39 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-28 12:39 [RFC PATCH 0/3] define new read_iter file operation rwf flag Mimi Zohar
2017-09-28 12:39 ` [RFC PATCH 1/3] fs: define new read_iter " Mimi Zohar
2017-09-28 13:54 ` Matthew Wilcox
2017-09-28 14:33 ` Mimi Zohar
2017-09-28 15:51 ` Linus Torvalds
2017-09-28 12:39 ` [RFC PATCH 2/3] integrity: use call_read_iter to calculate the file hash Mimi Zohar
2017-09-28 12:39 ` Mimi Zohar [this message]
2017-09-28 22:02 ` [RFC PATCH 3/3] fs: detect that the i_rwsem has already been taken exclusively Dave Chinner
2017-09-28 23:39 ` Linus Torvalds
2017-09-29 0:12 ` Mimi Zohar
2017-09-29 0:33 ` Linus Torvalds
2017-09-29 1:53 ` Mimi Zohar
2017-09-29 3:26 ` Linus Torvalds
2017-10-01 1:33 ` Eric W. Biederman
[not found] ` <CA+55aFx726wT4VprN-sHm6s8Q_PV_VjhTBC4goEbMcerYU1Tig@mail.gmail.com>
2017-10-01 12:08 ` Mimi Zohar
2017-10-01 18:41 ` Linus Torvalds
2017-10-01 22:34 ` Dave Chinner
2017-10-01 23:15 ` Linus Torvalds
2017-10-02 3:54 ` Dave Chinner
2017-10-01 23:42 ` Mimi Zohar
2017-10-02 3:25 ` Eric W. Biederman
2017-10-02 12:25 ` Mimi Zohar
2017-10-02 4:35 ` Dave Chinner
2017-10-02 12:09 ` Mimi Zohar
2017-10-02 12:43 ` Jeff Layton
2017-10-01 22:06 ` Eric W. Biederman
2017-10-01 22:20 ` Linus Torvalds
2017-10-01 23:54 ` Mimi Zohar
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