| Message ID | 20230726102603.155522-3-hao.xu@linux.dev (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | io_uring lseek | expand |
On Wed, Jul 26, 2023 at 06:25:58PM +0800, Hao Xu wrote: > From: Hao Xu <howeyxu@tencent.com> > > To support nowait llseek(), IOMAP_NOWAIT semantics should be respected. > In xfs, xfs_seek_iomap_begin() is the only place which may be blocked > by ilock and extent loading. Let's turn it into trylock logic just like > what we've done in xfs_readdir(). > > Signed-off-by: Hao Xu <howeyxu@tencent.com> > --- > fs/xfs/xfs_iomap.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c > index 18c8f168b153..bbd7c6b27701 100644 > --- a/fs/xfs/xfs_iomap.c > +++ b/fs/xfs/xfs_iomap.c > @@ -1294,7 +1294,9 @@ xfs_seek_iomap_begin( > if (xfs_is_shutdown(mp)) > return -EIO; > > - lockmode = xfs_ilock_data_map_shared(ip); > + lockmode = xfs_ilock_data_map_shared_generic(ip, flags & IOMAP_NOWAIT); What does this magic XFS function I can't find anywhere in this patch set do? -Dave.
On Thu, Jul 27, 2023 at 07:55:47AM +1000, Dave Chinner wrote: > On Wed, Jul 26, 2023 at 06:25:58PM +0800, Hao Xu wrote: > > From: Hao Xu <howeyxu@tencent.com> > > > > To support nowait llseek(), IOMAP_NOWAIT semantics should be respected. > > In xfs, xfs_seek_iomap_begin() is the only place which may be blocked > > by ilock and extent loading. Let's turn it into trylock logic just like > > what we've done in xfs_readdir(). > > > > Signed-off-by: Hao Xu <howeyxu@tencent.com> > > --- > > fs/xfs/xfs_iomap.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c > > index 18c8f168b153..bbd7c6b27701 100644 > > --- a/fs/xfs/xfs_iomap.c > > +++ b/fs/xfs/xfs_iomap.c > > @@ -1294,7 +1294,9 @@ xfs_seek_iomap_begin( > > if (xfs_is_shutdown(mp)) > > return -EIO; > > > > - lockmode = xfs_ilock_data_map_shared(ip); > > + lockmode = xfs_ilock_data_map_shared_generic(ip, flags & IOMAP_NOWAIT); > > What does this magic XFS function I can't find anywhere in this > patch set do? It's in (iirc) the io_uring getdents patchset that wasn't cc'd to linux-xfs and that I haven't looked at yet. --D > -Dave. > -- > Dave Chinner > david@fromorbit.com
On 7/27/23 06:14, Darrick J. Wong wrote: > On Thu, Jul 27, 2023 at 07:55:47AM +1000, Dave Chinner wrote: >> On Wed, Jul 26, 2023 at 06:25:58PM +0800, Hao Xu wrote: >>> From: Hao Xu <howeyxu@tencent.com> >>> >>> To support nowait llseek(), IOMAP_NOWAIT semantics should be respected. >>> In xfs, xfs_seek_iomap_begin() is the only place which may be blocked >>> by ilock and extent loading. Let's turn it into trylock logic just like >>> what we've done in xfs_readdir(). >>> >>> Signed-off-by: Hao Xu <howeyxu@tencent.com> >>> --- >>> fs/xfs/xfs_iomap.c | 4 +++- >>> 1 file changed, 3 insertions(+), 1 deletion(-) >>> >>> diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c >>> index 18c8f168b153..bbd7c6b27701 100644 >>> --- a/fs/xfs/xfs_iomap.c >>> +++ b/fs/xfs/xfs_iomap.c >>> @@ -1294,7 +1294,9 @@ xfs_seek_iomap_begin( >>> if (xfs_is_shutdown(mp)) >>> return -EIO; >>> >>> - lockmode = xfs_ilock_data_map_shared(ip); >>> + lockmode = xfs_ilock_data_map_shared_generic(ip, flags & IOMAP_NOWAIT); >> >> What does this magic XFS function I can't find anywhere in this >> patch set do? Sorry, forgot to say, It was xfs_ilock_for_readdir() in io_uring getdents patchset, I changed the name since it is now used for lseek as well. > > It's in (iirc) the io_uring getdents patchset that wasn't cc'd to > linux-xfs and that I haven't looked at yet. > Hi Darrick, I forwarded the xfs related patch in that series. Forgot to cc xfs list at the beginning. I'll make xfs list be Cc-ed when sending next version. Sorry for inconvenience. Regards, Hao > --D > >> -Dave. >> -- >> Dave Chinner >> david@fromorbit.com
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 18c8f168b153..bbd7c6b27701 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -1294,7 +1294,9 @@ xfs_seek_iomap_begin( if (xfs_is_shutdown(mp)) return -EIO; - lockmode = xfs_ilock_data_map_shared(ip); + lockmode = xfs_ilock_data_map_shared_generic(ip, flags & IOMAP_NOWAIT); + if (!lockmode) + return -EAGAIN; error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK); if (error) goto out_unlock;