From 690c2a38878e88d7182cf30d87864b565391d531 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 19 Oct 2019 09:09:45 -0700 Subject: [PATCH] xfs: split out a new set of read-only iomap ops Start untangling xfs_file_iomap_begin by splitting out the read-only case into its own set of iomap_ops with a very simply iomap_begin helper. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_aops.c | 9 ++++---- fs/xfs/xfs_file.c | 9 +++++--- fs/xfs/xfs_iomap.c | 63 ++++++++++++++++++++++++++++++++++++++++-------------- fs/xfs/xfs_iomap.h | 1 + fs/xfs/xfs_iops.c | 2 +- 5 files changed, 60 insertions(+), 24 deletions(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 5936507..5d3503f 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -634,7 +634,7 @@ xfs_vm_bmap( */ if (xfs_is_cow_inode(ip) || XFS_IS_REALTIME_INODE(ip)) return 0; - return iomap_bmap(mapping, block, &xfs_iomap_ops); + return iomap_bmap(mapping, block, &xfs_read_iomap_ops); } STATIC int @@ -642,7 +642,7 @@ xfs_vm_readpage( struct file *unused, struct page *page) { - return iomap_readpage(page, &xfs_iomap_ops); + return iomap_readpage(page, &xfs_read_iomap_ops); } STATIC int @@ -652,7 +652,7 @@ xfs_vm_readpages( struct list_head *pages, unsigned nr_pages) { - return iomap_readpages(mapping, pages, nr_pages, &xfs_iomap_ops); + return iomap_readpages(mapping, pages, nr_pages, &xfs_read_iomap_ops); } static int @@ -662,7 +662,8 @@ xfs_iomap_swapfile_activate( sector_t *span) { sis->bdev = xfs_find_bdev_for_inode(file_inode(swap_file)); - return iomap_swapfile_activate(sis, swap_file, span, &xfs_iomap_ops); + return iomap_swapfile_activate(sis, swap_file, span, + &xfs_read_iomap_ops); } const struct address_space_operations xfs_address_space_operations = { diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index c062013..e3299ff 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -188,7 +188,8 @@ xfs_file_dio_aio_read( file_accessed(iocb->ki_filp); xfs_ilock(ip, XFS_IOLOCK_SHARED); - ret = iomap_dio_rw(iocb, to, &xfs_iomap_ops, NULL, is_sync_kiocb(iocb)); + ret = iomap_dio_rw(iocb, to, &xfs_read_iomap_ops, NULL, + is_sync_kiocb(iocb)); xfs_iunlock(ip, XFS_IOLOCK_SHARED); return ret; @@ -215,7 +216,7 @@ xfs_file_dax_read( xfs_ilock(ip, XFS_IOLOCK_SHARED); } - ret = dax_iomap_rw(iocb, to, &xfs_iomap_ops); + ret = dax_iomap_rw(iocb, to, &xfs_read_iomap_ops); xfs_iunlock(ip, XFS_IOLOCK_SHARED); file_accessed(iocb->ki_filp); @@ -1153,7 +1154,9 @@ __xfs_filemap_fault( if (IS_DAX(inode)) { pfn_t pfn; - ret = dax_iomap_fault(vmf, pe_size, &pfn, NULL, &xfs_iomap_ops); + ret = dax_iomap_fault(vmf, pe_size, &pfn, NULL, + (write_fault && !vmf->cow_page) ? + &xfs_iomap_ops : &xfs_read_iomap_ops); if (ret & VM_FAULT_NEEDDSYNC) ret = dax_finish_sync_fault(vmf, pe_size, pfn); } else { diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 528b358..3bd1f7d 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -950,11 +950,13 @@ xfs_file_iomap_begin( u16 iomap_flags = 0; unsigned lockmode; + ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO)); + if (XFS_FORCED_SHUTDOWN(mp)) return -EIO; - if ((flags & (IOMAP_WRITE | IOMAP_ZERO)) && !(flags & IOMAP_DIRECT) && - !IS_DAX(inode) && !xfs_get_extsz_hint(ip)) { + if (!(flags & IOMAP_DIRECT) && !IS_DAX(inode) && + !xfs_get_extsz_hint(ip)) { /* Reserve delalloc blocks for regular writeback. */ return xfs_file_iomap_begin_delay(inode, offset, length, flags, iomap, srcmap); @@ -975,17 +977,6 @@ xfs_file_iomap_begin( if (error) goto out_unlock; - if (flags & IOMAP_REPORT) { - /* Trim the mapping to the nearest shared extent boundary. */ - error = xfs_reflink_trim_around_shared(ip, &imap, &shared); - if (error) - goto out_unlock; - } - - /* Non-modifying mapping requested, so we are done */ - if (!(flags & (IOMAP_WRITE | IOMAP_ZERO))) - goto out_found; - /* * Break shared extents if necessary. Checks for non-blocking IO have * been done up front, so we don't need to do them here. @@ -1051,10 +1042,8 @@ out_finish: * so consider them to be dirty for the purposes of O_DSYNC even if * there is no other metadata changes pending or have been made here. */ - if ((flags & IOMAP_WRITE) && offset + length > i_size_read(inode)) + if (offset + length > i_size_read(inode)) iomap_flags |= IOMAP_F_DIRTY; - if (shared) - iomap_flags |= IOMAP_F_SHARED; return xfs_bmbt_to_iomap(ip, iomap, &imap, iomap_flags); out_found: @@ -1158,6 +1147,48 @@ const struct iomap_ops xfs_iomap_ops = { }; static int +xfs_read_iomap_begin( + struct inode *inode, + loff_t offset, + loff_t length, + unsigned flags, + struct iomap *iomap, + struct iomap *srcmap) +{ + struct xfs_inode *ip = XFS_I(inode); + struct xfs_mount *mp = ip->i_mount; + struct xfs_bmbt_irec imap; + xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); + xfs_fileoff_t end_fsb = xfs_iomap_end_fsb(mp, offset, length); + int nimaps = 1, error = 0; + bool shared = false; + unsigned lockmode; + + ASSERT(!(flags & (IOMAP_WRITE | IOMAP_ZERO))); + + if (XFS_FORCED_SHUTDOWN(mp)) + return -EIO; + + error = xfs_ilock_for_iomap(ip, flags, &lockmode); + if (error) + return error; + error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, + &nimaps, 0); + if (!error && (flags & IOMAP_REPORT)) + error = xfs_reflink_trim_around_shared(ip, &imap, &shared); + xfs_iunlock(ip, lockmode); + + if (error) + return error; + trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap); + return xfs_bmbt_to_iomap(ip, iomap, &imap, shared ? IOMAP_F_SHARED : 0); +} + +const struct iomap_ops xfs_read_iomap_ops = { + .iomap_begin = xfs_read_iomap_begin, +}; + +static int xfs_seek_iomap_begin( struct inode *inode, loff_t offset, diff --git a/fs/xfs/xfs_iomap.h b/fs/xfs/xfs_iomap.h index 71d0ae4..61b1fc3 100644 --- a/fs/xfs/xfs_iomap.h +++ b/fs/xfs/xfs_iomap.h @@ -40,6 +40,7 @@ xfs_aligned_fsb_count( } extern const struct iomap_ops xfs_iomap_ops; +extern const struct iomap_ops xfs_read_iomap_ops; extern const struct iomap_ops xfs_seek_iomap_ops; extern const struct iomap_ops xfs_xattr_iomap_ops; diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c index fe285d1..9c448a5 100644 --- a/fs/xfs/xfs_iops.c +++ b/fs/xfs/xfs_iops.c @@ -1114,7 +1114,7 @@ xfs_vn_fiemap( &xfs_xattr_iomap_ops); } else { error = iomap_fiemap(inode, fieinfo, start, length, - &xfs_iomap_ops); + &xfs_read_iomap_ops); } xfs_iunlock(XFS_I(inode), XFS_IOLOCK_SHARED); -- 2.7.4