From 25219dbfa734e848fe4da84143f972d0301bb7c6 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 9 Oct 2020 16:42:59 -0700 Subject: [PATCH] xfs: fix fallocate functions when rtextsize is larger than 1 In commit fe341eb151ec, I forgot that xfs_free_file_space isn't strictly a "remove mapped blocks" function. It is actually a function to zero file space by punching out the middle and writing zeroes to the unaligned ends of the specified range. Therefore, putting a rtextsize alignment check in that function is wrong because that breaks unaligned ZERO_RANGE on the realtime volume. Furthermore, xfs_file_fallocate already has alignment checks for the functions require the file range to be aligned to the size of a fundamental allocation unit (which is 1 FSB on the data volume and 1 rt extent on the realtime volume). Create a new helper to check fallocate arguments against the realtiem allocation unit size, fix the fallocate frontend to use it, fix free_file_space to delete the correct range, and remove a now redundant check from insert_file_space. NOTE: The realtime extent size is not required to be a power of two! Fixes: fe341eb151ec ("xfs: ensure that fpunch, fcollapse, and finsert operations are aligned to rt extent size") Signed-off-by: Darrick J. Wong Reviewed-by: Chandan Babu R --- fs/xfs/xfs_bmap_util.c | 18 +++++------------- fs/xfs/xfs_file.c | 40 +++++++++++++++++++++++++++++++++++----- fs/xfs/xfs_linux.h | 6 ++++++ 3 files changed, 46 insertions(+), 18 deletions(-) diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index f2a8a0e75e1f..7371a7f7c652 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -947,11 +947,11 @@ xfs_free_file_space( endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len); /* We can only free complete realtime extents. */ - if (XFS_IS_REALTIME_INODE(ip)) { - xfs_extlen_t extsz = xfs_get_extsz_hint(ip); - - if ((startoffset_fsb | endoffset_fsb) & (extsz - 1)) - return -EINVAL; + if (XFS_IS_REALTIME_INODE(ip) && mp->m_sb.sb_rextsize > 1) { + startoffset_fsb = roundup_64(startoffset_fsb, + mp->m_sb.sb_rextsize); + endoffset_fsb = rounddown_64(endoffset_fsb, + mp->m_sb.sb_rextsize); } /* @@ -1147,14 +1147,6 @@ xfs_insert_file_space( trace_xfs_insert_file_space(ip); - /* We can only insert complete realtime extents. */ - if (XFS_IS_REALTIME_INODE(ip)) { - xfs_extlen_t extsz = xfs_get_extsz_hint(ip); - - if ((stop_fsb | shift_fsb) & (extsz - 1)) - return -EINVAL; - } - error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb); if (error) return error; diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 3d1b95124744..5b0f93f73837 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -32,6 +32,39 @@ static const struct vm_operations_struct xfs_file_vm_ops; +/* + * Decide if the given file range is aligned to the size of the fundamental + * allocation unit for the file. + */ +static bool +xfs_is_falloc_aligned( + struct xfs_inode *ip, + loff_t pos, + long long int len) +{ + struct xfs_mount *mp = ip->i_mount; + uint64_t mask; + + if (XFS_IS_REALTIME_INODE(ip)) { + if (!is_power_of_2(mp->m_sb.sb_rextsize)) { + u64 rextbytes; + u32 mod; + + rextbytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize); + div_u64_rem(pos, rextbytes, &mod); + if (mod) + return false; + div_u64_rem(len, rextbytes, &mod); + return mod == 0; + } + mask = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize) - 1; + } else { + mask = mp->m_sb.sb_blocksize - 1; + } + + return !((pos | len) & mask); +} + int xfs_update_prealloc_flags( struct xfs_inode *ip, @@ -850,9 +883,7 @@ xfs_file_fallocate( if (error) goto out_unlock; } else if (mode & FALLOC_FL_COLLAPSE_RANGE) { - unsigned int blksize_mask = i_blocksize(inode) - 1; - - if (offset & blksize_mask || len & blksize_mask) { + if (!xfs_is_falloc_aligned(ip, offset, len)) { error = -EINVAL; goto out_unlock; } @@ -872,10 +903,9 @@ xfs_file_fallocate( if (error) goto out_unlock; } else if (mode & FALLOC_FL_INSERT_RANGE) { - unsigned int blksize_mask = i_blocksize(inode) - 1; loff_t isize = i_size_read(inode); - if (offset & blksize_mask || len & blksize_mask) { + if (!xfs_is_falloc_aligned(ip, offset, len)) { error = -EINVAL; goto out_unlock; } diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h index ad1009778d33..5b7a1e201559 100644 --- a/fs/xfs/xfs_linux.h +++ b/fs/xfs/xfs_linux.h @@ -175,6 +175,12 @@ static inline xfs_dev_t linux_to_xfs_dev_t(dev_t dev) #define xfs_sort(a,n,s,fn) sort(a,n,s,fn,NULL) #define xfs_stack_trace() dump_stack() +static inline uint64_t rounddown_64(uint64_t x, uint32_t y) +{ + do_div(x, y); + return x * y; +} + static inline uint64_t roundup_64(uint64_t x, uint32_t y) { x += y - 1;