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Merge branch 'fallocate-insert-range' into for-next

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This commit is contained in:
Dave Chinner 2015-03-25 15:12:53 +11:00
parent 2b93681f59 a904b1ca57
commit a448f8f1b7
9 changed files with 497 additions and 92 deletions
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8
fs/open.c
View file

@ -231,8 +231,7 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
return -EINVAL;
/* Return error if mode is not supported */
if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
if (mode & ~FALLOC_FL_SUPPORTED_MASK)
return -EOPNOTSUPP;
/* Punch hole and zero range are mutually exclusive */
@ -250,6 +249,11 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
(mode & ~FALLOC_FL_COLLAPSE_RANGE))
return -EINVAL;
/* Insert range should only be used exclusively. */
if ((mode & FALLOC_FL_INSERT_RANGE) &&
(mode & ~FALLOC_FL_INSERT_RANGE))
return -EINVAL;
if (!(file->f_mode & FMODE_WRITE))
return -EBADF;

370
fs/xfs/libxfs/xfs_bmap.c
View file

@ -5486,52 +5486,92 @@ xfs_bmse_shift_one(
int *current_ext,
struct xfs_bmbt_rec_host *gotp,
struct xfs_btree_cur *cur,
int *logflags)
int *logflags,
enum shift_direction direction)
{
struct xfs_ifork *ifp;
struct xfs_mount *mp;
xfs_fileoff_t startoff;
struct xfs_bmbt_rec_host *leftp;
struct xfs_bmbt_rec_host *adj_irecp;
struct xfs_bmbt_irec got;
struct xfs_bmbt_irec left;
struct xfs_bmbt_irec adj_irec;
int error;
int i;
int total_extents;
mp = ip->i_mount;
ifp = XFS_IFORK_PTR(ip, whichfork);
total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
xfs_bmbt_get_all(gotp, &got);
startoff = got.br_startoff - offset_shift_fsb;
/* delalloc extents should be prevented by caller */
XFS_WANT_CORRUPTED_RETURN(mp, !isnullstartblock(got.br_startblock));
/*
* Check for merge if we've got an extent to the left, otherwise make
* sure there's enough room at the start of the file for the shift.
*/
if (*current_ext) {
/* grab the left extent and check for a large enough hole */
leftp = xfs_iext_get_ext(ifp, *current_ext - 1);
xfs_bmbt_get_all(leftp, &left);
if (direction == SHIFT_LEFT) {
startoff = got.br_startoff - offset_shift_fsb;
if (startoff < left.br_startoff + left.br_blockcount)
/*
* Check for merge if we've got an extent to the left,
* otherwise make sure there's enough room at the start
* of the file for the shift.
*/
if (!*current_ext) {
if (got.br_startoff < offset_shift_fsb)
return -EINVAL;
goto update_current_ext;
}
/*
* grab the left extent and check for a large
* enough hole.
*/
adj_irecp = xfs_iext_get_ext(ifp, *current_ext - 1);
xfs_bmbt_get_all(adj_irecp, &adj_irec);
if (startoff <
adj_irec.br_startoff + adj_irec.br_blockcount)
return -EINVAL;
/* check whether to merge the extent or shift it down */
if (xfs_bmse_can_merge(&left, &got, offset_shift_fsb)) {
if (xfs_bmse_can_merge(&adj_irec, &got,
offset_shift_fsb)) {
return xfs_bmse_merge(ip, whichfork, offset_shift_fsb,
*current_ext, gotp, leftp, cur,
logflags);
*current_ext, gotp, adj_irecp,
cur, logflags);
}
} else if (got.br_startoff < offset_shift_fsb)
return -EINVAL;
} else {
startoff = got.br_startoff + offset_shift_fsb;
/* nothing to move if this is the last extent */
if (*current_ext >= (total_extents - 1))
goto update_current_ext;
/*
* If this is not the last extent in the file, make sure there
* is enough room between current extent and next extent for
* accommodating the shift.
*/
adj_irecp = xfs_iext_get_ext(ifp, *current_ext + 1);
xfs_bmbt_get_all(adj_irecp, &adj_irec);
if (startoff + got.br_blockcount > adj_irec.br_startoff)
return -EINVAL;
/*
* Unlike a left shift (which involves a hole punch),
* a right shift does not modify extent neighbors
* in any way. We should never find mergeable extents
* in this scenario. Check anyways and warn if we
* encounter two extents that could be one.
*/
if (xfs_bmse_can_merge(&got, &adj_irec, offset_shift_fsb))
WARN_ON_ONCE(1);
}
/*
* Increment the extent index for the next iteration, update the start
* offset of the in-core extent and update the btree if applicable.
*/
(*current_ext)++;
update_current_ext:
if (direction == SHIFT_LEFT)
(*current_ext)++;
else
(*current_ext)--;
xfs_bmbt_set_startoff(gotp, startoff);
*logflags |= XFS_ILOG_CORE;
if (!cur) {
@ -5547,14 +5587,14 @@ xfs_bmse_shift_one(
got.br_startoff = startoff;
return xfs_bmbt_update(cur, got.br_startoff, got.br_startblock,
got.br_blockcount, got.br_state);
got.br_blockcount, got.br_state);
}
/*
* Shift extent records to the left to cover a hole.
* Shift extent records to the left/right to cover/create a hole.
*
* The maximum number of extents to be shifted in a single operation is
* @num_exts. @start_fsb specifies the file offset to start the shift and the
* @num_exts. @stop_fsb specifies the file offset at which to stop shift and the
* file offset where we've left off is returned in @next_fsb. @offset_shift_fsb
* is the length by which each extent is shifted. If there is no hole to shift
* the extents into, this will be considered invalid operation and we abort
@ -5564,12 +5604,13 @@ int
xfs_bmap_shift_extents(
struct xfs_trans *tp,
struct xfs_inode *ip,
xfs_fileoff_t start_fsb,
xfs_fileoff_t *next_fsb,
xfs_fileoff_t offset_shift_fsb,
int *done,
xfs_fileoff_t *next_fsb,
xfs_fileoff_t stop_fsb,
xfs_fsblock_t *firstblock,
struct xfs_bmap_free *flist,
enum shift_direction direction,
int num_exts)
{
struct xfs_btree_cur *cur = NULL;
@ -5579,10 +5620,11 @@ xfs_bmap_shift_extents(
struct xfs_ifork *ifp;
xfs_extnum_t nexts = 0;
xfs_extnum_t current_ext;
xfs_extnum_t total_extents;
xfs_extnum_t stop_extent;
int error = 0;
int whichfork = XFS_DATA_FORK;
int logflags = 0;
int total_extents;
if (unlikely(XFS_TEST_ERROR(
(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
@ -5598,6 +5640,8 @@ xfs_bmap_shift_extents(
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(direction == SHIFT_LEFT || direction == SHIFT_RIGHT);
ASSERT(*next_fsb != NULLFSBLOCK || direction == SHIFT_RIGHT);
ifp = XFS_IFORK_PTR(ip, whichfork);
if (!(ifp->if_flags & XFS_IFEXTENTS)) {
@ -5614,44 +5658,84 @@ xfs_bmap_shift_extents(
cur->bc_private.b.flags = 0;
}
/*
* Look up the extent index for the fsb where we start shifting. We can
* henceforth iterate with current_ext as extent list changes are locked
* out via ilock.
*
* 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.
*/
gotp = xfs_iext_bno_to_ext(ifp, start_fsb, &current_ext);
if (!gotp) {
*done = 1;
goto del_cursor;
}
/*
* There may be delalloc extents in the data fork before the range we
* are collapsing out, so we cannot use the count of real extents here.
* Instead we have to calculate it from the incore fork.
*/
total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
while (nexts++ < num_exts && current_ext < total_extents) {
if (total_extents == 0) {
*done = 1;
goto del_cursor;
}
/*
* In case of first right shift, we need to initialize next_fsb
*/
if (*next_fsb == NULLFSBLOCK) {
gotp = xfs_iext_get_ext(ifp, total_extents - 1);
xfs_bmbt_get_all(gotp, &got);
*next_fsb = got.br_startoff;
if (stop_fsb > *next_fsb) {
*done = 1;
goto del_cursor;
}
}
/* Lookup the extent index at which we have to stop */
if (direction == SHIFT_RIGHT) {
gotp = xfs_iext_bno_to_ext(ifp, stop_fsb, &stop_extent);
/* Make stop_extent exclusive of shift range */
stop_extent--;
} else
stop_extent = total_extents;
/*
* Look up the extent index for the fsb where we start shifting. We can
* henceforth iterate with current_ext as extent list changes are locked
* out via ilock.
*
* gotp can be null in 2 cases: 1) if there are no extents or 2)
* *next_fsb lies in a hole beyond which there are no extents. Either
* way, we are done.
*/
gotp = xfs_iext_bno_to_ext(ifp, *next_fsb, &current_ext);
if (!gotp) {
*done = 1;
goto del_cursor;
}
/* some sanity checking before we finally start shifting extents */
if ((direction == SHIFT_LEFT && current_ext >= stop_extent) ||
(direction == SHIFT_RIGHT && current_ext <= stop_extent)) {
error = -EIO;
goto del_cursor;
}
while (nexts++ < num_exts) {
error = xfs_bmse_shift_one(ip, whichfork, offset_shift_fsb,
&current_ext, gotp, cur, &logflags);
&current_ext, gotp, cur, &logflags,
direction);
if (error)
goto del_cursor;
/*
* If there was an extent merge during the shift, the extent
* count can change. Update the total and grade the next record.
*/
if (direction == SHIFT_LEFT) {
total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
stop_extent = total_extents;
}
/* update total extent count and grab the next record */
total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
if (current_ext >= total_extents)
if (current_ext == stop_extent) {
*done = 1;
*next_fsb = NULLFSBLOCK;
break;
}
gotp = xfs_iext_get_ext(ifp, current_ext);
}
/* Check if we are done */
if (current_ext == total_extents) {
*done = 1;
} else if (next_fsb) {
if (!*done) {
xfs_bmbt_get_all(gotp, &got);
*next_fsb = got.br_startoff;
}
@ -5666,3 +5750,189 @@ del_cursor:
return error;
}
/*
* Splits an extent into two extents at split_fsb block such that it is
* the first block of the current_ext. @current_ext is a target extent
* to be split. @split_fsb is a block where the extents is split.
* If split_fsb lies in a hole or the first block of extents, just return 0.
*/
STATIC int
xfs_bmap_split_extent_at(
struct xfs_trans *tp,
struct xfs_inode *ip,
xfs_fileoff_t split_fsb,
xfs_fsblock_t *firstfsb,
struct xfs_bmap_free *free_list)
{
int whichfork = XFS_DATA_FORK;
struct xfs_btree_cur *cur = NULL;
struct xfs_bmbt_rec_host *gotp;
struct xfs_bmbt_irec got;
struct xfs_bmbt_irec new; /* split extent */
struct xfs_mount *mp = ip->i_mount;
struct xfs_ifork *ifp;
xfs_fsblock_t gotblkcnt; /* new block count for got */
xfs_extnum_t current_ext;
int error = 0;
int logflags = 0;
int i = 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_split_extent_at",
XFS_ERRLEVEL_LOW, mp);
return -EFSCORRUPTED;
}
if (XFS_FORCED_SHUTDOWN(mp))
return -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;
}
/*
* gotp can be null in 2 cases: 1) if there are no extents
* or 2) split_fsb lies in a hole beyond which there are
* no extents. Either way, we are done.
*/
gotp = xfs_iext_bno_to_ext(ifp, split_fsb, &current_ext);
if (!gotp)
return 0;
xfs_bmbt_get_all(gotp, &got);
/*
* Check split_fsb lies in a hole or the start boundary offset
* of the extent.
*/
if (got.br_startoff >= split_fsb)
return 0;
gotblkcnt = split_fsb - got.br_startoff;
new.br_startoff = split_fsb;
new.br_startblock = got.br_startblock + gotblkcnt;
new.br_blockcount = got.br_blockcount - gotblkcnt;
new.br_state = got.br_state;
if (ifp->if_flags & XFS_IFBROOT) {
cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
cur->bc_private.b.firstblock = *firstfsb;
cur->bc_private.b.flist = free_list;
cur->bc_private.b.flags = 0;
error = xfs_bmbt_lookup_eq(cur, got.br_startoff,
got.br_startblock,
got.br_blockcount,
&i);
if (error)
goto del_cursor;
XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
}
xfs_bmbt_set_blockcount(gotp, gotblkcnt);
got.br_blockcount = gotblkcnt;
logflags = XFS_ILOG_CORE;
if (cur) {
error = xfs_bmbt_update(cur, got.br_startoff,
got.br_startblock,
got.br_blockcount,
got.br_state);
if (error)
goto del_cursor;
} else
logflags |= XFS_ILOG_DEXT;
/* Add new extent */
current_ext++;
xfs_iext_insert(ip, current_ext, 1, &new, 0);
XFS_IFORK_NEXT_SET(ip, whichfork,
XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
if (cur) {
error = xfs_bmbt_lookup_eq(cur, new.br_startoff,
new.br_startblock, new.br_blockcount,
&i);
if (error)
goto del_cursor;
XFS_WANT_CORRUPTED_GOTO(mp, i == 0, del_cursor);
cur->bc_rec.b.br_state = new.br_state;
error = xfs_btree_insert(cur, &i);
if (error)
goto del_cursor;
XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
}
/*
* Convert to a btree if necessary.
*/
if (xfs_bmap_needs_btree(ip, whichfork)) {
int tmp_logflags; /* partial log flag return val */
ASSERT(cur == NULL);
error = xfs_bmap_extents_to_btree(tp, ip, firstfsb, free_list,
&cur, 0, &tmp_logflags, whichfork);
logflags |= tmp_logflags;
}
del_cursor:
if (cur) {
cur->bc_private.b.allocated = 0;
xfs_btree_del_cursor(cur,
error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
}
if (logflags)
xfs_trans_log_inode(tp, ip, logflags);
return error;
}
int
xfs_bmap_split_extent(
struct xfs_inode *ip,
xfs_fileoff_t split_fsb)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp;
struct xfs_bmap_free free_list;
xfs_fsblock_t firstfsb;
int committed;
int error;
tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
XFS_DIOSTRAT_SPACE_RES(mp, 0), 0);
if (error) {
xfs_trans_cancel(tp, 0);
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_bmap_init(&free_list, &firstfsb);
error = xfs_bmap_split_extent_at(tp, ip, split_fsb,
&firstfsb, &free_list);
if (error)
goto out;
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error)
goto out;
return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
out:
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
return error;
}

13
fs/xfs/libxfs/xfs_bmap.h
View file

@ -166,6 +166,11 @@ static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
*/
#define XFS_BMAP_MAX_SHIFT_EXTENTS 1
enum shift_direction {
SHIFT_LEFT = 0,
SHIFT_RIGHT,
};
#ifdef DEBUG
void xfs_bmap_trace_exlist(struct xfs_inode *ip, xfs_extnum_t cnt,
int whichfork, unsigned long caller_ip);
@ -211,8 +216,10 @@ 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 *tp, struct xfs_inode *ip,
xfs_fileoff_t start_fsb, xfs_fileoff_t offset_shift_fsb,
int *done, xfs_fileoff_t *next_fsb, xfs_fsblock_t *firstblock,
struct xfs_bmap_free *flist, int num_exts);
xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
int *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
struct xfs_bmap_free *flist, enum shift_direction direction,
int num_exts);
int xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
#endif /* __XFS_BMAP_H__ */

131
fs/xfs/xfs_bmap_util.c
View file

@ -1376,22 +1376,19 @@ out:
}
/*
* xfs_collapse_file_space()
* This routine frees disk space and shift extent for the given file.
* 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. And Shift extent records to the left to cover a hole.
* RETURNS:
* 0 on success
* errno on error
*
* @next_fsb will keep track of the extent currently undergoing shift.
* @stop_fsb will keep track of the extent at which we have to stop.
* If we are shifting left, we will start with block (offset + len) and
* shift each extent till last extent.
* If we are shifting right, we will start with last extent inside file space
* and continue until we reach the block corresponding to offset.
*/
int
xfs_collapse_file_space(
struct xfs_inode *ip,
xfs_off_t offset,
xfs_off_t len)
xfs_shift_file_space(
struct xfs_inode *ip,
xfs_off_t offset,
xfs_off_t len,
enum shift_direction direction)
{
int done = 0;
struct xfs_mount *mp = ip->i_mount;
@ -1400,21 +1397,26 @@ xfs_collapse_file_space(
struct xfs_bmap_free free_list;
xfs_fsblock_t first_block;
int committed;
xfs_fileoff_t start_fsb;
xfs_fileoff_t stop_fsb;
xfs_fileoff_t next_fsb;
xfs_fileoff_t shift_fsb;
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
ASSERT(direction == SHIFT_LEFT || direction == SHIFT_RIGHT);
trace_xfs_collapse_file_space(ip);
if (direction == SHIFT_LEFT) {
next_fsb = XFS_B_TO_FSB(mp, offset + len);
stop_fsb = XFS_B_TO_FSB(mp, VFS_I(ip)->i_size);
} else {
/*
* If right shift, delegate the work of initialization of
* next_fsb to xfs_bmap_shift_extent as it has ilock held.
*/
next_fsb = NULLFSBLOCK;
stop_fsb = XFS_B_TO_FSB(mp, offset);
}
next_fsb = XFS_B_TO_FSB(mp, offset + len);
shift_fsb = XFS_B_TO_FSB(mp, len);
error = xfs_free_file_space(ip, offset, len);
if (error)
return error;
/*
* Trim eofblocks to avoid shifting uninitialized post-eof preallocation
* into the accessible region of the file.
@ -1427,20 +1429,28 @@ xfs_collapse_file_space(
/*
* Writeback and invalidate cache for the remainder of the file as we're
* about to shift down every extent from the collapse range to EOF. The
* free of the collapse range above might have already done some of
* this, but we shouldn't rely on it to do anything outside of the range
* that was freed.
* about to shift down every extent from offset to EOF.
*/
error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
offset + len, -1);
offset, -1);
if (error)
return error;
error = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
(offset + len) >> PAGE_CACHE_SHIFT, -1);
offset >> PAGE_CACHE_SHIFT, -1);
if (error)
return error;
/*
* The extent shiting code works on extent granularity. So, if
* stop_fsb is not the starting block of extent, we need to split
* the extent at stop_fsb.
*/
if (direction == SHIFT_RIGHT) {
error = xfs_bmap_split_extent(ip, stop_fsb);
if (error)
return error;
}
while (!error && !done) {
tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
/*
@ -1464,7 +1474,7 @@ xfs_collapse_file_space(
if (error)
goto out;
xfs_trans_ijoin(tp, ip, 0);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_bmap_init(&free_list, &first_block);
@ -1472,10 +1482,9 @@ xfs_collapse_file_space(
* We are using the write transaction in which max 2 bmbt
* updates are allowed
*/
start_fsb = next_fsb;
error = xfs_bmap_shift_extents(tp, ip, start_fsb, shift_fsb,
&done, &next_fsb, &first_block, &free_list,
XFS_BMAP_MAX_SHIFT_EXTENTS);
error = xfs_bmap_shift_extents(tp, ip, &next_fsb, shift_fsb,
&done, stop_fsb, &first_block, &free_list,
direction, XFS_BMAP_MAX_SHIFT_EXTENTS);
if (error)
goto out;
@ -1484,17 +1493,69 @@ xfs_collapse_file_space(
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_ILOCK_EXCL);
return error;
}
/*
* xfs_collapse_file_space()
* This routine frees disk space and shift extent for the given file.
* 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. And Shift extent records to the left to cover a hole.
* RETURNS:
* 0 on success
* errno on error
*
*/
int
xfs_collapse_file_space(
struct xfs_inode *ip,
xfs_off_t offset,
xfs_off_t len)
{
int error;
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
trace_xfs_collapse_file_space(ip);
error = xfs_free_file_space(ip, offset, len);
if (error)
return error;
return xfs_shift_file_space(ip, offset, len, SHIFT_LEFT);
}
/*
* xfs_insert_file_space()
* This routine create hole space by shifting extents for the given file.
* The first thing we do is to sync dirty data and invalidate page cache
* over the region on which insert range is working. And split an extent
* to two extents at given offset by calling xfs_bmap_split_extent.
* And shift all extent records which are laying between [offset,
* last allocated extent] to the right to reserve hole range.
* RETURNS:
* 0 on success
* errno on error
*/
int
xfs_insert_file_space(
struct xfs_inode *ip,
loff_t offset,
loff_t len)
{
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
trace_xfs_insert_file_space(ip);
return xfs_shift_file_space(ip, offset, len, SHIFT_RIGHT);
}
/*
* 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

2
fs/xfs/xfs_bmap_util.h
View file

@ -63,6 +63,8 @@ int xfs_zero_file_space(struct xfs_inode *ip, xfs_off_t offset,
xfs_off_t len);
int xfs_collapse_file_space(struct xfs_inode *, xfs_off_t offset,
xfs_off_t len);
int xfs_insert_file_space(struct xfs_inode *, xfs_off_t offset,
xfs_off_t len);
/* EOF block manipulation functions */
bool xfs_can_free_eofblocks(struct xfs_inode *ip, bool force);

41
fs/xfs/xfs_file.c
View file

@ -822,6 +822,11 @@ xfs_file_write_iter(
return ret;
}
#define XFS_FALLOC_FL_SUPPORTED \
(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
FALLOC_FL_INSERT_RANGE)
STATIC long
xfs_file_fallocate(
struct file *file,
@ -835,11 +840,11 @@ xfs_file_fallocate(
enum xfs_prealloc_flags flags = 0;
uint iolock = XFS_IOLOCK_EXCL;
loff_t new_size = 0;
bool do_file_insert = 0;
if (!S_ISREG(inode->i_mode))
return -EINVAL;
if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
if (mode & ~XFS_FALLOC_FL_SUPPORTED)
return -EOPNOTSUPP;
xfs_ilock(ip, iolock);
@ -876,6 +881,27 @@ xfs_file_fallocate(
error = xfs_collapse_file_space(ip, offset, len);
if (error)
goto out_unlock;
} else if (mode & FALLOC_FL_INSERT_RANGE) {
unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
new_size = i_size_read(inode) + len;
if (offset & blksize_mask || len & blksize_mask) {
error = -EINVAL;
goto out_unlock;
}
/* check the new inode size does not wrap through zero */
if (new_size > inode->i_sb->s_maxbytes) {
error = -EFBIG;
goto out_unlock;
}
/* Offset should be less than i_size */
if (offset >= i_size_read(inode)) {
error = -EINVAL;
goto out_unlock;
}
do_file_insert = 1;
} else {
flags |= XFS_PREALLOC_SET;
@ -910,8 +936,19 @@ xfs_file_fallocate(
iattr.ia_valid = ATTR_SIZE;
iattr.ia_size = new_size;
error = xfs_setattr_size(ip, &iattr);
if (error)
goto out_unlock;
}
/*
* Perform hole insertion now that the file size has been
* updated so that if we crash during the operation we don't
* leave shifted extents past EOF and hence losing access to
* the data that is contained within them.
*/
if (do_file_insert)
error = xfs_insert_file_space(ip, offset, len);
out_unlock:
xfs_iunlock(ip, iolock);
return error;

1
fs/xfs/xfs_trace.h
View file

@ -664,6 +664,7 @@ DEFINE_INODE_EVENT(xfs_alloc_file_space);
DEFINE_INODE_EVENT(xfs_free_file_space);
DEFINE_INODE_EVENT(xfs_zero_file_space);
DEFINE_INODE_EVENT(xfs_collapse_file_space);
DEFINE_INODE_EVENT(xfs_insert_file_space);
DEFINE_INODE_EVENT(xfs_readdir);
#ifdef CONFIG_XFS_POSIX_ACL
DEFINE_INODE_EVENT(xfs_get_acl);

6
include/linux/falloc.h
View file

@ -21,4 +21,10 @@ struct space_resv {
#define FS_IOC_RESVSP _IOW('X', 40, struct space_resv)
#define FS_IOC_RESVSP64 _IOW('X', 42, struct space_resv)
#define FALLOC_FL_SUPPORTED_MASK (FALLOC_FL_KEEP_SIZE | \
FALLOC_FL_PUNCH_HOLE | \
FALLOC_FL_COLLAPSE_RANGE | \
FALLOC_FL_ZERO_RANGE | \
FALLOC_FL_INSERT_RANGE)
#endif /* _FALLOC_H_ */

17
include/uapi/linux/falloc.h
View file

@ -41,4 +41,21 @@
*/
#define FALLOC_FL_ZERO_RANGE 0x10
/*
* FALLOC_FL_INSERT_RANGE is use to insert space within the file size without
* overwriting any existing data. The contents of the file beyond offset are
* shifted towards right by len bytes to create a hole. As such, this
* operation will increase the size of the file by len bytes.
*
* Different filesystems may implement different limitations on the granularity
* of the operation. Most will limit operations to filesystem block size
* boundaries, but this boundary may be larger or smaller depending on
* the filesystem and/or the configuration of the filesystem or file.
*
* Attempting to insert space using this flag at OR beyond the end of
* the file is considered an illegal operation - just use ftruncate(2) or
* fallocate(2) with mode 0 for such type of operations.
*/
#define FALLOC_FL_INSERT_RANGE 0x20
#endif /* _UAPI_FALLOC_H_ */