Message ID | 151701542824.3070.12415207450562775643.stgit@magnolia (mailing list archive) |
---|---|
State | Accepted, archived |
Headers | show |
Looks fine, although the fs.h addition would usually warrant a Cc to Al and fsdevel. (thus included as a full quote) Reviewed-by: Christoph Hellwig <hch@lst.de> On Fri, Jan 26, 2018 at 05:10:28PM -0800, Darrick J. Wong wrote: > From: Darrick J. Wong <darrick.wong@oracle.com> > > Reflink and dedupe operations remap blocks from a source file into a > destination file. The destination file needs exclusive locks on all > levels because we're updating its block map, but the source file isn't > undergoing any block map changes so we can use a shared lock. > > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> > --- > fs/xfs/xfs_reflink.c | 25 +++++++++++++++---------- > include/linux/fs.h | 5 +++++ > 2 files changed, 20 insertions(+), 10 deletions(-) > > > diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c > index bcc58c2..85a119e 100644 > --- a/fs/xfs/xfs_reflink.c > +++ b/fs/xfs/xfs_reflink.c > @@ -1202,13 +1202,16 @@ xfs_reflink_remap_blocks( > > /* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */ > while (len) { > + uint lock_mode; > + > trace_xfs_reflink_remap_blocks_loop(src, srcoff, len, > dest, destoff); > + > /* Read extent from the source file */ > nimaps = 1; > - xfs_ilock(src, XFS_ILOCK_EXCL); > + lock_mode = xfs_ilock_data_map_shared(src); > error = xfs_bmapi_read(src, srcoff, len, &imap, &nimaps, 0); > - xfs_iunlock(src, XFS_ILOCK_EXCL); > + xfs_iunlock(src, lock_mode); > if (error) > goto err; > ASSERT(nimaps == 1); > @@ -1260,7 +1263,7 @@ xfs_iolock_two_inodes_and_break_layout( > > retry: > if (src < dest) { > - inode_lock(src); > + inode_lock_shared(src); > inode_lock_nested(dest, I_MUTEX_NONDIR2); > } else { > /* src >= dest */ > @@ -1271,7 +1274,7 @@ xfs_iolock_two_inodes_and_break_layout( > if (error == -EWOULDBLOCK) { > inode_unlock(dest); > if (src < dest) > - inode_unlock(src); > + inode_unlock_shared(src); > error = break_layout(dest, true); > if (error) > return error; > @@ -1280,11 +1283,11 @@ xfs_iolock_two_inodes_and_break_layout( > if (error) { > inode_unlock(dest); > if (src < dest) > - inode_unlock(src); > + inode_unlock_shared(src); > return error; > } > if (src > dest) > - inode_lock_nested(src, I_MUTEX_NONDIR2); > + inode_lock_shared_nested(src, I_MUTEX_NONDIR2); > return 0; > } > > @@ -1324,7 +1327,7 @@ xfs_reflink_remap_range( > if (same_inode) > xfs_ilock(src, XFS_MMAPLOCK_EXCL); > else > - xfs_lock_two_inodes(src, XFS_MMAPLOCK_EXCL, dest, > + xfs_lock_two_inodes(src, XFS_MMAPLOCK_SHARED, dest, > XFS_MMAPLOCK_EXCL); > > /* Check file eligibility and prepare for block sharing. */ > @@ -1393,10 +1396,12 @@ xfs_reflink_remap_range( > is_dedupe); > > out_unlock: > - xfs_iunlock(src, XFS_MMAPLOCK_EXCL); > + xfs_iunlock(dest, XFS_MMAPLOCK_EXCL); > + if (!same_inode) > + xfs_iunlock(src, XFS_MMAPLOCK_SHARED); > + inode_unlock(inode_out); > if (!same_inode) > - xfs_iunlock(dest, XFS_MMAPLOCK_EXCL); > - unlock_two_nondirectories(inode_in, inode_out); > + inode_unlock_shared(inode_in); > if (ret) > trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_); > return ret; > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 7f8d96d..5cbeab8 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -748,6 +748,11 @@ static inline void inode_lock_nested(struct inode *inode, unsigned subclass) > down_write_nested(&inode->i_rwsem, subclass); > } > > +static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass) > +{ > + down_read_nested(&inode->i_rwsem, subclass); > +} > + > void lock_two_nondirectories(struct inode *, struct inode*); > void unlock_two_nondirectories(struct inode *, struct inode*); > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html ---end quoted text--- -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index bcc58c2..85a119e 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -1202,13 +1202,16 @@ xfs_reflink_remap_blocks( /* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */ while (len) { + uint lock_mode; + trace_xfs_reflink_remap_blocks_loop(src, srcoff, len, dest, destoff); + /* Read extent from the source file */ nimaps = 1; - xfs_ilock(src, XFS_ILOCK_EXCL); + lock_mode = xfs_ilock_data_map_shared(src); error = xfs_bmapi_read(src, srcoff, len, &imap, &nimaps, 0); - xfs_iunlock(src, XFS_ILOCK_EXCL); + xfs_iunlock(src, lock_mode); if (error) goto err; ASSERT(nimaps == 1); @@ -1260,7 +1263,7 @@ xfs_iolock_two_inodes_and_break_layout( retry: if (src < dest) { - inode_lock(src); + inode_lock_shared(src); inode_lock_nested(dest, I_MUTEX_NONDIR2); } else { /* src >= dest */ @@ -1271,7 +1274,7 @@ xfs_iolock_two_inodes_and_break_layout( if (error == -EWOULDBLOCK) { inode_unlock(dest); if (src < dest) - inode_unlock(src); + inode_unlock_shared(src); error = break_layout(dest, true); if (error) return error; @@ -1280,11 +1283,11 @@ xfs_iolock_two_inodes_and_break_layout( if (error) { inode_unlock(dest); if (src < dest) - inode_unlock(src); + inode_unlock_shared(src); return error; } if (src > dest) - inode_lock_nested(src, I_MUTEX_NONDIR2); + inode_lock_shared_nested(src, I_MUTEX_NONDIR2); return 0; } @@ -1324,7 +1327,7 @@ xfs_reflink_remap_range( if (same_inode) xfs_ilock(src, XFS_MMAPLOCK_EXCL); else - xfs_lock_two_inodes(src, XFS_MMAPLOCK_EXCL, dest, + xfs_lock_two_inodes(src, XFS_MMAPLOCK_SHARED, dest, XFS_MMAPLOCK_EXCL); /* Check file eligibility and prepare for block sharing. */ @@ -1393,10 +1396,12 @@ xfs_reflink_remap_range( is_dedupe); out_unlock: - xfs_iunlock(src, XFS_MMAPLOCK_EXCL); + xfs_iunlock(dest, XFS_MMAPLOCK_EXCL); + if (!same_inode) + xfs_iunlock(src, XFS_MMAPLOCK_SHARED); + inode_unlock(inode_out); if (!same_inode) - xfs_iunlock(dest, XFS_MMAPLOCK_EXCL); - unlock_two_nondirectories(inode_in, inode_out); + inode_unlock_shared(inode_in); if (ret) trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_); return ret; diff --git a/include/linux/fs.h b/include/linux/fs.h index 7f8d96d..5cbeab8 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -748,6 +748,11 @@ static inline void inode_lock_nested(struct inode *inode, unsigned subclass) down_write_nested(&inode->i_rwsem, subclass); } +static inline void inode_lock_shared_nested(struct inode *inode, unsigned subclass) +{ + down_read_nested(&inode->i_rwsem, subclass); +} + void lock_two_nondirectories(struct inode *, struct inode*); void unlock_two_nondirectories(struct inode *, struct inode*);