The patch titled
Subject: btrfs: nowait aio support
has been added to the -mm tree. Its filename is
btrfs-nowait-aio-support.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/btrfs-nowait-aio-support.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/btrfs-nowait-aio-support.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
Subject: btrfs: nowait aio support
Return EAGAIN if any of the following checks fail
+ i_rwsem is not lockable
+ NODATACOW or PREALLOC is not set
+ Cannot nocow at the desired location
+ Writing beyond end of file which is not allocated
Link: http://lkml.kernel.org/r/20170615160002.17233-11-rgoldwyn@xxxxxxx
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
Acked-by: David Sterba <dsterba@xxxxxxxx>
Cc: "Theodore Ts'o" <tytso@xxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Andreas Dilger <adilger.kernel@xxxxxxxxx>
Cc: Chris Mason <clm@xxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Josef Bacik <jbacik@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/file.c | 33 +++++++++++++++++++++++++++------
fs/btrfs/inode.c | 3 +++
2 files changed, 30 insertions(+), 6 deletions(-)
diff -puN fs/btrfs/file.c~btrfs-nowait-aio-support fs/btrfs/file.c
--- a/fs/btrfs/file.c~btrfs-nowait-aio-support
+++ a/fs/btrfs/file.c
@@ -1875,12 +1875,29 @@ static ssize_t btrfs_file_write_iter(str
ssize_t num_written = 0;
bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host);
ssize_t err;
- loff_t pos;
- size_t count;
+ loff_t pos = iocb->ki_pos;
+ size_t count = iov_iter_count(from);
loff_t oldsize;
int clean_page = 0;
- inode_lock(inode);
+ if ((iocb->ki_flags & IOCB_NOWAIT) &&
+ (iocb->ki_flags & IOCB_DIRECT)) {
+ /* Don't sleep on inode rwsem */
+ if (!inode_trylock(inode))
+ return -EAGAIN;
+ /*
+ * We will allocate space in case nodatacow is not set,
+ * so bail
+ */
+ if (!(BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW |
+ BTRFS_INODE_PREALLOC)) ||
+ check_can_nocow(BTRFS_I(inode), pos, &count) <= 0) {
+ inode_unlock(inode);
+ return -EAGAIN;
+ }
+ } else
+ inode_lock(inode);
+
err = generic_write_checks(iocb, from);
if (err <= 0) {
inode_unlock(inode);
@@ -1914,8 +1931,6 @@ static ssize_t btrfs_file_write_iter(str
*/
update_time_for_write(inode);
- pos = iocb->ki_pos;
- count = iov_iter_count(from);
start_pos = round_down(pos, fs_info->sectorsize);
oldsize = i_size_read(inode);
if (start_pos > oldsize) {
@@ -3071,13 +3086,19 @@ out:
return offset;
}
+static int btrfs_file_open(struct inode *inode, struct file *filp)
+{
+ filp->f_mode |= FMODE_AIO_NOWAIT;
+ return generic_file_open(inode, filp);
+}
+
const struct file_operations btrfs_file_operations = {
.llseek = btrfs_file_llseek,
.read_iter = generic_file_read_iter,
.splice_read = generic_file_splice_read,
.write_iter = btrfs_file_write_iter,
.mmap = btrfs_file_mmap,
- .open = generic_file_open,
+ .open = btrfs_file_open,
.release = btrfs_release_file,
.fsync = btrfs_sync_file,
.fallocate = btrfs_fallocate,
diff -puN fs/btrfs/inode.c~btrfs-nowait-aio-support fs/btrfs/inode.c
--- a/fs/btrfs/inode.c~btrfs-nowait-aio-support
+++ a/fs/btrfs/inode.c
@@ -8755,6 +8755,9 @@ static ssize_t btrfs_direct_IO(struct ki
dio_data.overwrite = 1;
inode_unlock(inode);
relock = true;
+ } else if (iocb->ki_flags & IOCB_NOWAIT) {
+ ret = -EAGAIN;
+ goto out;
}
ret = btrfs_delalloc_reserve_space(inode, offset, count);
if (ret)
_
Patches currently in -mm which might be from rgoldwyn@xxxxxxxx are
fs-separate-out-kiocb-flags-setup-based-on-rwf_-flags.patch
fs-introduce-filemap_range_has_page.patch
fs-use-rwf_-flags-for-aio-operations.patch
fs-introduce-rwf_nowait-and-fmode_aio_nowait.patch
fs-return-if-direct-write-will-trigger-writeback.patch
fs-introduce-iomap_nowait.patch
block-return-on-congested-block-device.patch
ext4-nowait-aio-support.patch
xfs-nowait-aio-support.patch
btrfs-nowait-aio-support.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
