From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
Add support FALLOC_FL_COLLAPSE_RANGE for fallocate.
Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
Signed-off-by: Ashish Sangwan <a.sangwan@xxxxxxxxxxx>
---
fs/xfs/xfs_bmap.c | 174 ++++++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/xfs_bmap.h | 3 +
fs/xfs/xfs_bmap_util.c | 96 ++++++++++++++++++++++++++
fs/xfs/xfs_bmap_util.h | 2 +
fs/xfs/xfs_file.c | 20 ++++--
fs/xfs/xfs_fs.h | 6 ++
6 files changed, 296 insertions(+), 5 deletions(-)
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 92b8309..c12358e 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -5356,3 +5356,177 @@ error0:
}
return error;
}
+
+/*
+ * Update extents by shifting them downwards into a hole.
+ * At max count number of extents will be shifted and *current_ext
+ * is the extent number which is currently being shifted.
+ * This function will return error if the hole is not present
+ * while shifting extents. On success, 0 is returned.
+ */
+int
+xfs_bmap_shift_extents(
+ struct xfs_trans *tp,
+ struct xfs_inode *ip,
+ int *done,
+ xfs_fileoff_t start_fsb,
+ xfs_fileoff_t shift,
+ xfs_extnum_t *current_ext,
+ xfs_fsblock_t *firstblock,
+ struct xfs_bmap_free *flist,
+ int count)
+{
+ struct xfs_btree_cur *cur;
+ struct xfs_bmbt_rec_host *gotp;
+ struct xfs_bmbt_irec left;
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_ifork *ifp;
+ xfs_extnum_t nexts = 0;
+ xfs_fileoff_t startoff;
+ int error = 0;
+ int i;
+ int whichfork = XFS_DATA_FORK;
+ int state;
+ int logflags;
+ xfs_filblks_t blockcount = 0;
+
+ if (unlikely(XFS_TEST_ERROR(
+ (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
+ XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
+ mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
+ XFS_ERROR_REPORT("xfs_bmap_shift_extents",
+ XFS_ERRLEVEL_LOW, mp);
+ return XFS_ERROR(EFSCORRUPTED);
+ }
+
+ if (XFS_FORCED_SHUTDOWN(mp))
+ return XFS_ERROR(EIO);
+
+ ifp = XFS_IFORK_PTR(ip, whichfork);
+
+ if (!(ifp->if_flags & XFS_IFEXTENTS)) {
+ /* Read in all the extents */
+ error = xfs_iread_extents(tp, ip, whichfork);
+ if (error)
+ return error;
+ }
+
+ if (!*current_ext) {
+ gotp = xfs_iext_bno_to_ext(ifp, start_fsb, current_ext);
+ /*
+ * gotp can be null in 2 cases: 1) if there are no extents
+ * or 2) start_fsb lies in a hole beyond which there are
+ * no extents. Either way, we are done.
+ */
+ if (!gotp) {
+ *done = 1;
+ return 0;
+ }
+ }
+
+ /* We are going to change core inode */
+ logflags = XFS_ILOG_CORE;
+
+ if (ifp->if_flags & XFS_IFBROOT) {
+ cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
+ cur->bc_private.b.firstblock = *firstblock;
+ cur->bc_private.b.flist = flist;
+ cur->bc_private.b.flags = 0;
+ }
+ else {
+ cur = NULL;
+ logflags |= XFS_ILOG_DEXT;
+ }
+
+ while (nexts++ < count &&
+ *current_ext < XFS_IFORK_NEXTENTS(ip, whichfork)) {
+ state = 0;
+
+ gotp = xfs_iext_get_ext(ifp, *current_ext);
+ startoff = xfs_bmbt_get_startoff(gotp);
+ startoff -= shift;
+
+ /*
+ * Before shifting extent into hole, make sure that the hole
+ * is large enough to accomodate the shift.
+ */
+ if (*current_ext) {
+ state |= BMAP_LEFT_VALID;
+ xfs_bmbt_get_all(xfs_iext_get_ext(ifp,
+ *current_ext - 1), &left);
+
+ if (isnullstartblock(left.br_startblock))
+ state |= BMAP_LEFT_DELAY;
+
+ if (startoff < left.br_startoff + left.br_blockcount)
+ error = XFS_ERROR(EFSCORRUPTED);
+
+ } else if (startoff > xfs_bmbt_get_startoff(gotp))
+ /* Hole is at the start but not large enough */
+ error = XFS_ERROR(EFSCORRUPTED);
+
+ if (error)
+ goto del_cursor;
+
+ /* Check if we can merge 2 adjacent extents */
+ if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
+ left.br_startoff + left.br_blockcount == startoff &&
+ left.br_startblock + left.br_blockcount ==
+ xfs_bmbt_get_startblock(gotp) &&
+ xfs_bmbt_get_state(gotp) == left.br_state &&
+ left.br_blockcount + xfs_bmbt_get_blockcount(gotp) <=
+ MAXEXTLEN) {
+ blockcount =
+ left.br_blockcount + xfs_bmbt_get_blockcount(gotp);
+ state |= BMAP_LEFT_CONTIG;
+ xfs_iext_remove(ip, *current_ext, 1, 0);
+ XFS_IFORK_NEXT_SET(ip, whichfork,
+ XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
+ gotp = xfs_iext_get_ext(ifp, --*current_ext);
+ }
+
+ if (cur) {
+ error = xfs_bmbt_lookup_eq(cur,
+ xfs_bmbt_get_startoff(gotp),
+ xfs_bmbt_get_startblock(gotp),
+ xfs_bmbt_get_blockcount(gotp),
+ &i);
+ if (error)
+ goto del_cursor;
+ XFS_WANT_CORRUPTED_GOTO(i == 1, del_cursor);
+ }
+
+ if (state & BMAP_LEFT_CONTIG) {
+ /* We have to update extent block count */
+ xfs_bmbt_set_blockcount(gotp, blockcount);
+ } else {
+ /* We have to update the startoff */
+ xfs_bmbt_set_startoff(gotp, startoff);
+ }
+
+ if (cur) {
+ error = xfs_bmbt_update(cur,
+ xfs_bmbt_get_startoff(gotp),
+ xfs_bmbt_get_startblock(gotp),
+ xfs_bmbt_get_blockcount(gotp),
+ xfs_bmbt_get_state(gotp));
+ if (error)
+ goto del_cursor;
+ }
+
+ (*current_ext)++;
+ }
+
+ /* Check if we are done */
+ if (*current_ext == XFS_IFORK_NEXTENTS(ip, whichfork))
+ *done = 1;
+
+del_cursor:
+ if (cur)
+ xfs_btree_del_cursor(cur,
+ error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
+
+ xfs_trans_log_inode(tp, ip, logflags);
+
+ return error;
+}
diff --git a/fs/xfs/xfs_bmap.h b/fs/xfs/xfs_bmap.h
index 33b41f3..b16ebfa 100644
--- a/fs/xfs/xfs_bmap.h
+++ b/fs/xfs/xfs_bmap.h
@@ -169,5 +169,8 @@ int xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
int xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
xfs_extnum_t num);
uint xfs_default_attroffset(struct xfs_inode *ip);
+int xfs_bmap_shift_extents(struct xfs_trans *, struct xfs_inode *,
+ int *, xfs_fileoff_t, xfs_fileoff_t, xfs_extnum_t *,
+ xfs_fsblock_t *, struct xfs_bmap_free *, int);
#endif /* __XFS_BMAP_H__ */
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 541d59f..57f045e 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1556,6 +1556,7 @@ xfs_change_file_space(
case XFS_IOC_RESVSP64:
case XFS_IOC_UNRESVSP:
case XFS_IOC_UNRESVSP64:
+ case XFS_COLLAPSE_RANGE:
if (bf->l_len <= 0)
return XFS_ERROR(EINVAL);
break;
@@ -1638,6 +1639,12 @@ xfs_change_file_space(
clrprealloc = 1;
break;
+ case XFS_COLLAPSE_RANGE:
+ error = xfs_collapse_file_space(ip, startoffset, bf->l_len,
+ attr_flags);
+ if (error)
+ return error;
+ break;
default:
ASSERT(0);
@@ -1683,6 +1690,95 @@ xfs_change_file_space(
return xfs_trans_commit(tp, 0);
}
+
+/*
+ * xfs_collapse_file_space: Implements the FALLOC_FL_COLLAPSE_SPACE flag.
+ */
+int
+xfs_collapse_file_space(
+ struct xfs_inode *ip,
+ loff_t offset,
+ loff_t len,
+ int attr_flags)
+{
+ int done = 0;
+ struct xfs_mount *mp = ip->i_mount;
+ uint resblks;
+ struct xfs_trans *tp;
+ int error;
+ xfs_extnum_t current_ext = 0;
+ struct xfs_bmap_free free_list;
+ xfs_fsblock_t first_block;
+ int committed;
+ xfs_fileoff_t start_fsb = XFS_B_TO_FSB(mp, offset + len);
+ xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len);
+
+ resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
+
+ /*
+ * The first thing we do is to free data blocks in the specified range
+ * by calling xfs_free_file_space(). It would also sync dirty data
+ * and invalidate page cache over the region on which collapse range
+ * is working.
+ */
+
+ error = xfs_free_file_space(ip, offset, len, attr_flags);
+ if (error)
+ return error;
+
+ while (!error && !done) {
+ tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
+ tp->t_flags |= XFS_TRANS_RESERVE;
+ /*
+ * We would need to reserve permanent block for transaction.
+ * This will come into picture when after shifting extent into
+ * hole we found that adjacent extents can be merged which
+ * may lead to freeing of a block during record update.
+ */
+ error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write, resblks, 0);
+ if (error) {
+ ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
+ xfs_trans_cancel(tp, 0);
+ break;
+ }
+
+ xfs_ilock(ip, XFS_ILOCK_EXCL);
+ error = xfs_trans_reserve_quota(tp, mp,
+ ip->i_udquot, ip->i_gdquot, ip->i_pdquot,
+ resblks, 0, XFS_QMOPT_RES_REGBLKS);
+ if (error)
+ goto out;
+
+ xfs_trans_ijoin(tp, ip, 0);
+
+ xfs_bmap_init(&free_list, &first_block);
+
+ /*
+ * We are using the write transaction in which max 2 bmbt
+ * updates are allowed
+ */
+ error = xfs_bmap_shift_extents(tp, ip, &done, start_fsb,
+ shift_fsb, ¤t_ext,
+ &first_block, &free_list, 2);
+ if (error)
+ goto out;
+
+ error = xfs_bmap_finish(&tp, &free_list, &committed);
+ if (error)
+ goto out;
+
+ error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ }
+
+ return error;
+
+out:
+ xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
+ xfs_iunlock(ip, XFS_IOLOCK_EXCL);
+ return error;
+}
+
/*
* We need to check that the format of the data fork in the temporary inode is
* valid for the target inode before doing the swap. This is not a problem with
diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
index 0612609..588d29d 100644
--- a/fs/xfs/xfs_bmap_util.h
+++ b/fs/xfs/xfs_bmap_util.h
@@ -97,6 +97,8 @@ int xfs_change_file_space(struct xfs_inode *ip, int cmd,
xfs_flock64_t *bf, xfs_off_t offset,
int attr_flags);
+int xfs_collapse_file_space(struct xfs_inode *, loff_t, loff_t, int);
+
/* EOF block manipulation functions */
bool xfs_can_free_eofblocks(struct xfs_inode *ip, bool force);
int xfs_free_eofblocks(struct xfs_mount *mp, struct xfs_inode *ip,
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 818c623..9c9c1ff 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -807,7 +807,8 @@ xfs_file_fallocate(
int cmd = XFS_IOC_RESVSP;
int attr_flags = XFS_ATTR_NOLOCK;
- if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+ if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
+ FALLOC_FL_COLLAPSE_RANGE))
return -EOPNOTSUPP;
bf.l_whence = 0;
@@ -819,10 +820,19 @@ xfs_file_fallocate(
if (mode & FALLOC_FL_PUNCH_HOLE)
cmd = XFS_IOC_UNRESVSP;
- /* check the new inode size is valid before allocating */
- if (!(mode & FALLOC_FL_KEEP_SIZE) &&
- offset + len > i_size_read(inode)) {
+ /* Shrink size in case of FALLOC_FL_COLLAPSE_RANGE */
+ if (mode & FALLOC_FL_COLLAPSE_RANGE) {
+ cmd = XFS_COLLAPSE_RANGE;
+ if ((offset + len) > i_size_read(inode))
+ new_size = offset;
+ else
+ new_size = i_size_read(inode) - len;
+ } else if (!(mode & FALLOC_FL_KEEP_SIZE) &&
+ offset + len > i_size_read(inode))
new_size = offset + len;
+
+ /* check the new inode size is valid before allocating */
+ if (new_size || mode & FALLOC_FL_COLLAPSE_RANGE) {
error = inode_newsize_ok(inode, new_size);
if (error)
goto out_unlock;
@@ -836,7 +846,7 @@ xfs_file_fallocate(
goto out_unlock;
/* Change file size if needed */
- if (new_size) {
+ if (new_size || mode & FALLOC_FL_COLLAPSE_RANGE) {
struct iattr iattr;
iattr.ia_valid = ATTR_SIZE;
diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
index 1edb5cc..99f5244 100644
--- a/fs/xfs/xfs_fs.h
+++ b/fs/xfs/xfs_fs.h
@@ -516,6 +516,12 @@ typedef struct xfs_swapext
#define XFS_IOC_GETBMAPX _IOWR('X', 56, struct getbmap)
#define XFS_IOC_ZERO_RANGE _IOW ('X', 57, struct xfs_flock64)
#define XFS_IOC_FREE_EOFBLOCKS _IOR ('X', 58, struct xfs_eofblocks)
+/*
+ * Although there is no ioctl implemented yet, we reserve an ioctl number for
+ * representing collapse range operation to avoid any possible collision in
+ * switch case of xfs_change_file_space.
+ */
+#define XFS_COLLAPSE_RANGE _IOW('X', 59, struct xfs_flock64)
/*
* ioctl commands that replace IRIX syssgi()'s
--
1.7.9.5
--
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