[PATCH 20/27] xfs: move xfs_getbmap to xfs_extent_ops.c

Dave Chinner
2013-06-12T10:23:31Z

From: Dave Chinner <dchinner@redhat.com>

While xfs_getbmap() walks the extent tree and formats it for
userspace, it's not really a core function of the block mapping API.
It is a user of the interface, and one that is kernel only
functionality. xfs_bmap.c is shared with libxfs, so to minimise the
differences between userspace and kernel files, move the getbmap
functionality to xfs_extent_ops.c. This provides a nice separation
between the core functionality and implementation of kernel
interfaces.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_bmap.c | 281 ----------------------------------------------
fs/xfs/xfs_bmap.h | 5 -
fs/xfs/xfs_extent_ops.c | 283 +++++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/xfs_extent_ops.h | 6 +
fs/xfs/xfs_iops.c | 1 +
5 files changed, 290 insertions(+), 286 deletions(-)

diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 747f2d3..7b8b3ab 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -5790,287 +5790,6 @@ error0:
}

/*
- * returns 1 for success, 0 if we failed to map the extent.
- */
-STATIC int
-xfs_getbmapx_fix_eof_hole(
- xfs_inode_t *ip, /* xfs incore inode pointer */
- struct getbmapx *out, /* output structure */
- int prealloced, /* this is a file with
- * preallocated data space */
- __int64_t end, /* last block requested */
- xfs_fsblock_t startblock)
-{
- __int64_t fixlen;
- xfs_mount_t *mp; /* file system mount point */
- xfs_ifork_t *ifp; /* inode fork pointer */
- xfs_extnum_t lastx; /* last extent pointer */
- xfs_fileoff_t fileblock;
-
- if (startblock == HOLESTARTBLOCK) {
- mp = ip->i_mount;
- out->bmv_block = -1;
- fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, XFS_ISIZE(ip)));
- fixlen -= out->bmv_offset;
- if (prealloced && out->bmv_offset + out->bmv_length == end) {
- /* Came to hole at EOF. Trim it. */
- if (fixlen <= 0)
- return 0;
- out->bmv_length = fixlen;
- }
- } else {
- if (startblock == DELAYSTARTBLOCK)
- out->bmv_block = -2;
- else
- out->bmv_block = xfs_fsb_to_db(ip, startblock);
- fileblock = XFS_BB_TO_FSB(ip->i_mount, out->bmv_offset);
- ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
- if (xfs_iext_bno_to_ext(ifp, fileblock, &lastx) &&
- (lastx == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))-1))
- out->bmv_oflags |= BMV_OF_LAST;
- }
-
- return 1;
-}
-
-/*
- * Get inode's extents as described in bmv, and format for output.
- * Calls formatter to fill the user's buffer until all extents
- * are mapped, until the passed-in bmv->bmv_count slots have
- * been filled, or until the formatter short-circuits the loop,
- * if it is tracking filled-in extents on its own.
- */
-int /* error code */
-xfs_getbmap(
- xfs_inode_t *ip,
- struct getbmapx *bmv, /* user bmap structure */
- xfs_bmap_format_t formatter, /* format to user */
- void *arg) /* formatter arg */
-{
- __int64_t bmvend; /* last block requested */
- int error = 0; /* return value */
- __int64_t fixlen; /* length for -1 case */
- int i; /* extent number */
- int lock; /* lock state */
- xfs_bmbt_irec_t *map; /* buffer for user's data */
- xfs_mount_t *mp; /* file system mount point */
- int nex; /* # of user extents can do */
- int nexleft; /* # of user extents left */
- int subnex; /* # of bmapi's can do */
- int nmap; /* number of map entries */
- struct getbmapx *out; /* output structure */
- int whichfork; /* data or attr fork */
- int prealloced; /* this is a file with
- * preallocated data space */
- int iflags; /* interface flags */
- int bmapi_flags; /* flags for xfs_bmapi */
- int cur_ext = 0;
-
- mp = ip->i_mount;
- iflags = bmv->bmv_iflags;
- whichfork = iflags & BMV_IF_ATTRFORK ? XFS_ATTR_FORK : XFS_DATA_FORK;
-
- if (whichfork == XFS_ATTR_FORK) {
- if (XFS_IFORK_Q(ip)) {
- if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS &&
- ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE &&
- ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)
- return XFS_ERROR(EINVAL);
- } else if (unlikely(
- ip->i_d.di_aformat != 0 &&
- ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS)) {
- XFS_ERROR_REPORT("xfs_getbmap", XFS_ERRLEVEL_LOW,
- ip->i_mount);
- return XFS_ERROR(EFSCORRUPTED);
- }
-
- prealloced = 0;
- fixlen = 1LL << 32;
- } else {
- if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS &&
- ip->i_d.di_format != XFS_DINODE_FMT_BTREE &&
- ip->i_d.di_format != XFS_DINODE_FMT_LOCAL)
- return XFS_ERROR(EINVAL);
-
- if (xfs_get_extsz_hint(ip) ||
- ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC|XFS_DIFLAG_APPEND)){
- prealloced = 1;
- fixlen = mp->m_super->s_maxbytes;
- } else {
- prealloced = 0;
- fixlen = XFS_ISIZE(ip);
- }
- }
-
- if (bmv->bmv_length == -1) {
- fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, fixlen));
- bmv->bmv_length =
- max_t(__int64_t, fixlen - bmv->bmv_offset, 0);
- } else if (bmv->bmv_length == 0) {
- bmv->bmv_entries = 0;
- return 0;
- } else if (bmv->bmv_length < 0) {
- return XFS_ERROR(EINVAL);
- }
-
- nex = bmv->bmv_count - 1;
- if (nex <= 0)
- return XFS_ERROR(EINVAL);
- bmvend = bmv->bmv_offset + bmv->bmv_length;
-
-
- 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)) {
- if (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size) {
- error = -filemap_write_and_wait(VFS_I(ip)->i_mapping);
- if (error)
- goto out_unlock_iolock;
- }
- /*
- * even after flushing the inode, there can still be delalloc
- * blocks on the inode beyond EOF due to speculative
- * preallocation. These are not removed until the release
- * function is called or the inode is inactivated. Hence we
- * cannot assert here that ip->i_delayed_blks == 0.
- */
- }
-
- lock = xfs_ilock_map_shared(ip);
-
- /*
- * Don't let nex be bigger than the number of extents
- * we can have assuming alternating holes and real extents.
- */
- if (nex > XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1)
- nex = XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1;
-
- bmapi_flags = xfs_bmapi_aflag(whichfork);
- if (!(iflags & BMV_IF_PREALLOC))
- bmapi_flags |= XFS_BMAPI_IGSTATE;
-
- /*
- * Allocate enough space to handle "subnex" maps at a time.
- */
- error = ENOMEM;
- subnex = 16;
- map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS);
- if (!map)
- goto out_unlock_ilock;
-
- bmv->bmv_entries = 0;
-
- if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0 &&
- (whichfork == XFS_ATTR_FORK || !(iflags & BMV_IF_DELALLOC))) {
- error = 0;
- goto out_free_map;
- }
-
- nexleft = nex;
-
- do {
- nmap = (nexleft > subnex) ? subnex : nexleft;
- error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset),
- XFS_BB_TO_FSB(mp, bmv->bmv_length),
- map, &nmap, bmapi_flags);
- if (error)
- goto out_free_map;
- ASSERT(nmap <= subnex);
-
- for (i = 0; i < nmap && nexleft && bmv->bmv_length; i++) {
- out[cur_ext].bmv_oflags = 0;
- if (map[i].br_state == XFS_EXT_UNWRITTEN)
- out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC;
- else if (map[i].br_startblock == DELAYSTARTBLOCK)
- out[cur_ext].bmv_oflags |= BMV_OF_DELALLOC;
- out[cur_ext].bmv_offset =
- XFS_FSB_TO_BB(mp, map[i].br_startoff);
- out[cur_ext].bmv_length =
- XFS_FSB_TO_BB(mp, map[i].br_blockcount);
- out[cur_ext].bmv_unused1 = 0;
- out[cur_ext].bmv_unused2 = 0;
-
- /*
- * delayed allocation extents that start beyond EOF can
- * occur due to speculative EOF allocation when the
- * delalloc extent is larger than the largest freespace
- * extent at conversion time. These extents cannot be
- * converted by data writeback, so can exist here even
- * if we are not supposed to be finding delalloc
- * extents.
- */
- if (map[i].br_startblock == DELAYSTARTBLOCK &&
- map[i].br_startoff <= XFS_B_TO_FSB(mp, XFS_ISIZE(ip)))
- ASSERT((iflags & BMV_IF_DELALLOC) != 0);
-
- if (map[i].br_startblock == HOLESTARTBLOCK &&
- whichfork == XFS_ATTR_FORK) {
- /* came to the end of attribute fork */
- out[cur_ext].bmv_oflags |= BMV_OF_LAST;
- goto out_free_map;
- }
-
- if (!xfs_getbmapx_fix_eof_hole(ip, &out[cur_ext],
- prealloced, bmvend,
- map[i].br_startblock))
- goto out_free_map;
-
- bmv->bmv_offset =
- out[cur_ext].bmv_offset +
- out[cur_ext].bmv_length;
- bmv->bmv_length =
- max_t(__int64_t, 0, bmvend - bmv->bmv_offset);
-
- /*
- * In case we don't want to return the hole,
- * don't increase cur_ext so that we can reuse
- * it in the next loop.
- */
- if ((iflags & BMV_IF_NO_HOLES) &&
- map[i].br_startblock == HOLESTARTBLOCK) {
- memset(&out[cur_ext], 0, sizeof(out[cur_ext]));
- continue;
- }
-
- nexleft--;
- bmv->bmv_entries++;
- cur_ext++;
- }
- } while (nmap && nexleft && bmv->bmv_length);
-
- out_free_map:
- kmem_free(map);
- out_unlock_ilock:
- xfs_iunlock_map_shared(ip, lock);
- out_unlock_iolock:
- xfs_iunlock(ip, XFS_IOLOCK_SHARED);
-
- for (i = 0; i < cur_ext; i++) {
- int full = 0; /* user array is full */
-
- /* format results & advance arg */
- error = formatter(&arg, &out[i], &full);
- if (error || full)
- break;
- }
-
- if (is_vmalloc_addr(out))
- kmem_free_large(out);
- else
- kmem_free(out);
- return error;
-}
-
-/*
* dead simple method of punching delalyed allocation blocks from a range in
* the inode. Walks a block at a time so will be slow, but is only executed in
* rare error cases so the overhead is not critical. This will alays punch out
diff --git a/fs/xfs/xfs_bmap.h b/fs/xfs/xfs_bmap.h
index 1cf1292..cbcaf00 100644
--- a/fs/xfs/xfs_bmap.h
+++ b/fs/xfs/xfs_bmap.h
@@ -18,7 +18,6 @@
#ifndef __XFS_BMAP_H__
#define __XFS_BMAP_H__

-struct getbmap;
struct xfs_bmbt_irec;
struct xfs_ifork;
struct xfs_inode;
@@ -206,13 +205,9 @@ int xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
uint xfs_default_attroffset(struct xfs_inode *ip);

#ifdef __KERNEL__
-/* bmap to userspace formatter - copy to user & advance pointer */
-typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *, int *);

int xfs_bmap_finish(struct xfs_trans **tp, struct xfs_bmap_free *flist,
int *committed);
-int xfs_getbmap(struct xfs_inode *ip, struct getbmapx *bmv,
- xfs_bmap_format_t formatter, void *arg);
int xfs_bmap_eof(struct xfs_inode *ip, xfs_fileoff_t endoff,
int whichfork, int *eof);
int xfs_bmap_count_blocks(struct xfs_trans *tp, struct xfs_inode *ip,
diff --git a/fs/xfs/xfs_extent_ops.c b/fs/xfs/xfs_extent_ops.c
index 113d682..2702a3c 100644
--- a/fs/xfs/xfs_extent_ops.c
+++ b/fs/xfs/xfs_extent_ops.c
@@ -48,6 +48,7 @@
#include "xfs_filestream.h"
#include "xfs_trace.h"
#include "xfs_icache.h"
+#include "xfs_extent_ops.h"

/*
@@ -769,3 +770,285 @@ xfs_change_file_space(
xfs_trans_set_sync(tp);
return xfs_trans_commit(tp, 0);
}
+
+/*
+ * returns 1 for success, 0 if we failed to map the extent.
+ */
+STATIC int
+xfs_getbmapx_fix_eof_hole(
+ xfs_inode_t *ip, /* xfs incore inode pointer */
+ struct getbmapx *out, /* output structure */
+ int prealloced, /* this is a file with
+ * preallocated data space */
+ __int64_t end, /* last block requested */
+ xfs_fsblock_t startblock)
+{
+ __int64_t fixlen;
+ xfs_mount_t *mp; /* file system mount point */
+ xfs_ifork_t *ifp; /* inode fork pointer */
+ xfs_extnum_t lastx; /* last extent pointer */
+ xfs_fileoff_t fileblock;
+
+ if (startblock == HOLESTARTBLOCK) {
+ mp = ip->i_mount;
+ out->bmv_block = -1;
+ fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, XFS_ISIZE(ip)));
+ fixlen -= out->bmv_offset;
+ if (prealloced && out->bmv_offset + out->bmv_length == end) {
+ /* Came to hole at EOF. Trim it. */
+ if (fixlen <= 0)
+ return 0;
+ out->bmv_length = fixlen;
+ }
+ } else {
+ if (startblock == DELAYSTARTBLOCK)
+ out->bmv_block = -2;
+ else
+ out->bmv_block = xfs_fsb_to_db(ip, startblock);
+ fileblock = XFS_BB_TO_FSB(ip->i_mount, out->bmv_offset);
+ ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
+ if (xfs_iext_bno_to_ext(ifp, fileblock, &lastx) &&
+ (lastx == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))-1))
+ out->bmv_oflags |= BMV_OF_LAST;
+ }
+
+ return 1;
+}
+
+/*
+ * Get inode's extents as described in bmv, and format for output.
+ * Calls formatter to fill the user's buffer until all extents
+ * are mapped, until the passed-in bmv->bmv_count slots have
+ * been filled, or until the formatter short-circuits the loop,
+ * if it is tracking filled-in extents on its own.
+ */
+int /* error code */
+xfs_getbmap(
+ xfs_inode_t *ip,
+ struct getbmapx *bmv, /* user bmap structure */
+ xfs_bmap_format_t formatter, /* format to user */
+ void *arg) /* formatter arg */
+{
+ __int64_t bmvend; /* last block requested */
+ int error = 0; /* return value */
+ __int64_t fixlen; /* length for -1 case */
+ int i; /* extent number */
+ int lock; /* lock state */
+ xfs_bmbt_irec_t *map; /* buffer for user's data */
+ xfs_mount_t *mp; /* file system mount point */
+ int nex; /* # of user extents can do */
+ int nexleft; /* # of user extents left */
+ int subnex; /* # of bmapi's can do */
+ int nmap; /* number of map entries */
+ struct getbmapx *out; /* output structure */
+ int whichfork; /* data or attr fork */
+ int prealloced; /* this is a file with
+ * preallocated data space */
+ int iflags; /* interface flags */
+ int bmapi_flags; /* flags for xfs_bmapi */
+ int cur_ext = 0;
+
+ mp = ip->i_mount;
+ iflags = bmv->bmv_iflags;
+ whichfork = iflags & BMV_IF_ATTRFORK ? XFS_ATTR_FORK : XFS_DATA_FORK;
+
+ if (whichfork == XFS_ATTR_FORK) {
+ if (XFS_IFORK_Q(ip)) {
+ if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS &&
+ ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE &&
+ ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)
+ return XFS_ERROR(EINVAL);
+ } else if (unlikely(
+ ip->i_d.di_aformat != 0 &&
+ ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS)) {
+ XFS_ERROR_REPORT("xfs_getbmap", XFS_ERRLEVEL_LOW,
+ ip->i_mount);
+ return XFS_ERROR(EFSCORRUPTED);
+ }
+
+ prealloced = 0;
+ fixlen = 1LL << 32;
+ } else {
+ if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS &&
+ ip->i_d.di_format != XFS_DINODE_FMT_BTREE &&
+ ip->i_d.di_format != XFS_DINODE_FMT_LOCAL)
+ return XFS_ERROR(EINVAL);
+
+ if (xfs_get_extsz_hint(ip) ||
+ ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC|XFS_DIFLAG_APPEND)){
+ prealloced = 1;
+ fixlen = mp->m_super->s_maxbytes;
+ } else {
+ prealloced = 0;
+ fixlen = XFS_ISIZE(ip);
+ }
+ }
+
+ if (bmv->bmv_length == -1) {
+ fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, fixlen));
+ bmv->bmv_length =
+ max_t(__int64_t, fixlen - bmv->bmv_offset, 0);
+ } else if (bmv->bmv_length == 0) {
+ bmv->bmv_entries = 0;
+ return 0;
+ } else if (bmv->bmv_length < 0) {
+ return XFS_ERROR(EINVAL);
+ }
+
+ nex = bmv->bmv_count - 1;
+ if (nex <= 0)
+ return XFS_ERROR(EINVAL);
+ bmvend = bmv->bmv_offset + bmv->bmv_length;
+
+
+ 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)) {
+ if (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size) {
+ error = -filemap_write_and_wait(VFS_I(ip)->i_mapping);
+ if (error)
+ goto out_unlock_iolock;
+ }
+ /*
+ * even after flushing the inode, there can still be delalloc
+ * blocks on the inode beyond EOF due to speculative
+ * preallocation. These are not removed until the release
+ * function is called or the inode is inactivated. Hence we
+ * cannot assert here that ip->i_delayed_blks == 0.
+ */
+ }
+
+ lock = xfs_ilock_map_shared(ip);
+
+ /*
+ * Don't let nex be bigger than the number of extents
+ * we can have assuming alternating holes and real extents.
+ */
+ if (nex > XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1)
+ nex = XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1;
+
+ bmapi_flags = xfs_bmapi_aflag(whichfork);
+ if (!(iflags & BMV_IF_PREALLOC))
+ bmapi_flags |= XFS_BMAPI_IGSTATE;
+
+ /*
+ * Allocate enough space to handle "subnex" maps at a time.
+ */
+ error = ENOMEM;
+ subnex = 16;
+ map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS);
+ if (!map)
+ goto out_unlock_ilock;
+
+ bmv->bmv_entries = 0;
+
+ if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0 &&
+ (whichfork == XFS_ATTR_FORK || !(iflags & BMV_IF_DELALLOC))) {
+ error = 0;
+ goto out_free_map;
+ }
+
+ nexleft = nex;
+
+ do {
+ nmap = (nexleft > subnex) ? subnex : nexleft;
+ error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset),
+ XFS_BB_TO_FSB(mp, bmv->bmv_length),
+ map, &nmap, bmapi_flags);
+ if (error)
+ goto out_free_map;
+ ASSERT(nmap <= subnex);
+
+ for (i = 0; i < nmap && nexleft && bmv->bmv_length; i++) {
+ out[cur_ext].bmv_oflags = 0;
+ if (map[i].br_state == XFS_EXT_UNWRITTEN)
+ out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC;
+ else if (map[i].br_startblock == DELAYSTARTBLOCK)
+ out[cur_ext].bmv_oflags |= BMV_OF_DELALLOC;
+ out[cur_ext].bmv_offset =
+ XFS_FSB_TO_BB(mp, map[i].br_startoff);
+ out[cur_ext].bmv_length =
+ XFS_FSB_TO_BB(mp, map[i].br_blockcount);
+ out[cur_ext].bmv_unused1 = 0;
+ out[cur_ext].bmv_unused2 = 0;
+
+ /*
+ * delayed allocation extents that start beyond EOF can
+ * occur due to speculative EOF allocation when the
+ * delalloc extent is larger than the largest freespace
+ * extent at conversion time. These extents cannot be
+ * converted by data writeback, so can exist here even
+ * if we are not supposed to be finding delalloc
+ * extents.
+ */
+ if (map[i].br_startblock == DELAYSTARTBLOCK &&
+ map[i].br_startoff <= XFS_B_TO_FSB(mp, XFS_ISIZE(ip)))
+ ASSERT((iflags & BMV_IF_DELALLOC) != 0);
+
+ if (map[i].br_startblock == HOLESTARTBLOCK &&
+ whichfork == XFS_ATTR_FORK) {
+ /* came to the end of attribute fork */
+ out[cur_ext].bmv_oflags |= BMV_OF_LAST;
+ goto out_free_map;
+ }
+
+ if (!xfs_getbmapx_fix_eof_hole(ip, &out[cur_ext],
+ prealloced, bmvend,
+ map[i].br_startblock))
+ goto out_free_map;
+
+ bmv->bmv_offset =
+ out[cur_ext].bmv_offset +
+ out[cur_ext].bmv_length;
+ bmv->bmv_length =
+ max_t(__int64_t, 0, bmvend - bmv->bmv_offset);
+
+ /*
+ * In case we don't want to return the hole,
+ * don't increase cur_ext so that we can reuse
+ * it in the next loop.
+ */
+ if ((iflags & BMV_IF_NO_HOLES) &&
+ map[i].br_startblock == HOLESTARTBLOCK) {
+ memset(&out[cur_ext], 0, sizeof(out[cur_ext]));
+ continue;
+ }
+
+ nexleft--;
+ bmv->bmv_entries++;
+ cur_ext++;
+ }
+ } while (nmap && nexleft && bmv->bmv_length);
+
+ out_free_map:
+ kmem_free(map);
+ out_unlock_ilock:
+ xfs_iunlock_map_shared(ip, lock);
+ out_unlock_iolock:
+ xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+
+ for (i = 0; i < cur_ext; i++) {
+ int full = 0; /* user array is full */
+
+ /* format results & advance arg */
+ error = formatter(&arg, &out[i], &full);
+ if (error || full)
+ break;
+ }
+
+ if (is_vmalloc_addr(out))
+ kmem_free_large(out);
+ else
+ kmem_free(out);
+ return error;
+}
+
diff --git a/fs/xfs/xfs_extent_ops.h b/fs/xfs/xfs_extent_ops.h
index a737640..550a37d 100644
--- a/fs/xfs/xfs_extent_ops.h
+++ b/fs/xfs/xfs_extent_ops.h
@@ -21,4 +21,10 @@
int xfs_change_file_space(struct xfs_inode *ip, int cmd,
xfs_flock64_t *bf, xfs_off_t offset, int attr_flags);

+/* bmap to userspace formatter - copy to user & advance pointer */
+typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *, int *);
+
+int xfs_getbmap(struct xfs_inode *ip, struct getbmapx *bmv,
+ xfs_bmap_format_t formatter, void *arg);
+
#endif /* _XFS_EXTENT_OPS_H */
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 7f44efa..99775a2 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -39,6 +39,7 @@
#include "xfs_trace.h"
#include "xfs_icache.h"
#include "xfs_symlink.h"
+#include "xfs_extent_ops.h"

#include <linux/capability.h>
#include <linux/xattr.h>
--
1.7.10.4