Commit f074211f authored Mar 07, 2012 by Dave Chinner Committed by Ben Myers Mar 15, 2012

xfs: fallback to vmalloc for large buffers in xfs_getbmap



xfs_getbmap uses for a large buffer for extents, which is kmalloc'd.
This can fail after the system has been running for some time as it
is a high order allocation. Add a fallback to vmalloc so that it
doesn't require contiguous memory and so won't randomly fail on
files with large extent lists.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

parent ad650f5b

fs/xfs/xfs_bmap.c

+10 −3

Original line number	Diff line number	Diff line
		@@ -5536,8 +5536,12 @@ xfs_getbmap(
		if (bmv->bmv_count > ULONG_MAX / sizeof(struct getbmapx))
		return XFS_ERROR(ENOMEM);
		out = kmem_zalloc(bmv->bmv_count * sizeof(struct getbmapx), KM_MAYFAIL);
		if (!out) {
		out = kmem_zalloc_large(bmv->bmv_count *
		sizeof(struct getbmapx));
		if (!out)
		return XFS_ERROR(ENOMEM);
		}

		xfs_ilock(ip, XFS_IOLOCK_SHARED);
		if (whichfork == XFS_DATA_FORK && !(iflags & BMV_IF_DELALLOC)) {
		@@ -5661,6 +5665,9 @@ xfs_getbmap(
		break;
		}

		if (is_vmalloc_addr(out))
		kmem_free_large(out);
		else
		kmem_free(out);
		return error;
		}