Commit 25219dbf authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: fix fallocate functions when rtextsize is larger than 1 



In commit fe341eb1, 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: fe341eb1 ("xfs: ensure that fpunch, fcollapse, and finsert operations are aligned to rt extent size")
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarChandan Babu R <chandanrlinux@gmail.com>
parent 89464554

fs/xfs/xfs_bmap_util.c

+5 −13
Original line number Diff line number Diff line
@@ -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;

fs/xfs/xfs_file.c

+35 −5
Original line number Diff line number Diff line
@@ -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;

		}

fs/xfs/xfs_linux.h

+6 −0
Original line number Diff line number Diff line
@@ -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;

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