2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
10 #include <linux/spinlock.h>
11 #include <linux/completion.h>
12 #include <linux/buffer_head.h>
13 #include <linux/blkdev.h>
14 #include <linux/gfs2_ondisk.h>
15 #include <linux/crc32.h>
16 #include <linux/iomap.h>
17 #include <linux/ktime.h>
33 #include "trace_gfs2.h"
35 /* This doesn't need to be that large as max 64 bit pointers in a 4k
36 * block is 512, so __u16 is fine for that. It saves stack space to
40 struct buffer_head *mp_bh[GFS2_MAX_META_HEIGHT];
41 __u16 mp_list[GFS2_MAX_META_HEIGHT];
42 int mp_fheight; /* find_metapath height */
43 int mp_aheight; /* actual height (lookup height) */
46 static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length);
49 * gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page
51 * @dibh: the dinode buffer
52 * @block: the block number that was allocated
53 * @page: The (optional) page. This is looked up if @page is NULL
58 static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh,
59 u64 block, struct page *page)
61 struct inode *inode = &ip->i_inode;
62 struct buffer_head *bh;
65 if (!page || page->index) {
66 page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);
72 if (!PageUptodate(page)) {
73 void *kaddr = kmap(page);
74 u64 dsize = i_size_read(inode);
76 if (dsize > gfs2_max_stuffed_size(ip))
77 dsize = gfs2_max_stuffed_size(ip);
79 memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
80 memset(kaddr + dsize, 0, PAGE_SIZE - dsize);
83 SetPageUptodate(page);
86 if (!page_has_buffers(page))
87 create_empty_buffers(page, BIT(inode->i_blkbits),
90 bh = page_buffers(page);
92 if (!buffer_mapped(bh))
93 map_bh(bh, inode->i_sb, block);
95 set_buffer_uptodate(bh);
96 if (gfs2_is_jdata(ip))
97 gfs2_trans_add_data(ip->i_gl, bh);
99 mark_buffer_dirty(bh);
100 gfs2_ordered_add_inode(ip);
112 * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big
113 * @ip: The GFS2 inode to unstuff
114 * @page: The (optional) page. This is looked up if the @page is NULL
116 * This routine unstuffs a dinode and returns it to a "normal" state such
117 * that the height can be grown in the traditional way.
122 int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page)
124 struct buffer_head *bh, *dibh;
125 struct gfs2_dinode *di;
127 int isdir = gfs2_is_dir(ip);
130 down_write(&ip->i_rw_mutex);
132 error = gfs2_meta_inode_buffer(ip, &dibh);
136 if (i_size_read(&ip->i_inode)) {
137 /* Get a free block, fill it with the stuffed data,
138 and write it out to disk */
141 error = gfs2_alloc_blocks(ip, &block, &n, 0, NULL);
145 gfs2_trans_remove_revoke(GFS2_SB(&ip->i_inode), block, 1);
146 error = gfs2_dir_get_new_buffer(ip, block, &bh);
149 gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_meta_header),
150 dibh, sizeof(struct gfs2_dinode));
153 error = gfs2_unstuffer_page(ip, dibh, block, page);
159 /* Set up the pointer to the new block */
161 gfs2_trans_add_meta(ip->i_gl, dibh);
162 di = (struct gfs2_dinode *)dibh->b_data;
163 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
165 if (i_size_read(&ip->i_inode)) {
166 *(__be64 *)(di + 1) = cpu_to_be64(block);
167 gfs2_add_inode_blocks(&ip->i_inode, 1);
168 di->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
172 di->di_height = cpu_to_be16(1);
177 up_write(&ip->i_rw_mutex);
183 * find_metapath - Find path through the metadata tree
184 * @sdp: The superblock
185 * @block: The disk block to look up
186 * @mp: The metapath to return the result in
187 * @height: The pre-calculated height of the metadata tree
189 * This routine returns a struct metapath structure that defines a path
190 * through the metadata of inode "ip" to get to block "block".
193 * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
194 * filesystem with a blocksize of 4096.
196 * find_metapath() would return a struct metapath structure set to:
197 * mp_fheight = 3, mp_list[0] = 0, mp_list[1] = 48, and mp_list[2] = 165.
199 * That means that in order to get to the block containing the byte at
200 * offset 101342453, we would load the indirect block pointed to by pointer
201 * 0 in the dinode. We would then load the indirect block pointed to by
202 * pointer 48 in that indirect block. We would then load the data block
203 * pointed to by pointer 165 in that indirect block.
205 * ----------------------------------------
210 * ----------------------------------------
214 * ----------------------------------------
218 * |0 5 6 7 8 9 0 1 2|
219 * ----------------------------------------
223 * ----------------------------------------
228 * ----------------------------------------
232 * ----------------------------------------
233 * | Data block containing offset |
237 * ----------------------------------------
241 static void find_metapath(const struct gfs2_sbd *sdp, u64 block,
242 struct metapath *mp, unsigned int height)
246 mp->mp_fheight = height;
247 for (i = height; i--;)
248 mp->mp_list[i] = do_div(block, sdp->sd_inptrs);
251 static inline unsigned int metapath_branch_start(const struct metapath *mp)
253 if (mp->mp_list[0] == 0)
259 * metaptr1 - Return the first possible metadata pointer in a metapath buffer
260 * @height: The metadata height (0 = dinode)
263 static inline __be64 *metaptr1(unsigned int height, const struct metapath *mp)
265 struct buffer_head *bh = mp->mp_bh[height];
267 return ((__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)));
268 return ((__be64 *)(bh->b_data + sizeof(struct gfs2_meta_header)));
272 * metapointer - Return pointer to start of metadata in a buffer
273 * @height: The metadata height (0 = dinode)
276 * Return a pointer to the block number of the next height of the metadata
277 * tree given a buffer containing the pointer to the current height of the
281 static inline __be64 *metapointer(unsigned int height, const struct metapath *mp)
283 __be64 *p = metaptr1(height, mp);
284 return p + mp->mp_list[height];
287 static inline const __be64 *metaend(unsigned int height, const struct metapath *mp)
289 const struct buffer_head *bh = mp->mp_bh[height];
290 return (const __be64 *)(bh->b_data + bh->b_size);
293 static void clone_metapath(struct metapath *clone, struct metapath *mp)
298 for (hgt = 0; hgt < mp->mp_aheight; hgt++)
299 get_bh(clone->mp_bh[hgt]);
302 static void gfs2_metapath_ra(struct gfs2_glock *gl, __be64 *start, __be64 *end)
306 for (t = start; t < end; t++) {
307 struct buffer_head *rabh;
312 rabh = gfs2_getbuf(gl, be64_to_cpu(*t), CREATE);
313 if (trylock_buffer(rabh)) {
314 if (!buffer_uptodate(rabh)) {
315 rabh->b_end_io = end_buffer_read_sync;
316 submit_bh(REQ_OP_READ,
317 REQ_RAHEAD | REQ_META | REQ_PRIO,
327 static int __fillup_metapath(struct gfs2_inode *ip, struct metapath *mp,
328 unsigned int x, unsigned int h)
331 __be64 *ptr = metapointer(x, mp);
332 u64 dblock = be64_to_cpu(*ptr);
337 ret = gfs2_meta_indirect_buffer(ip, x + 1, dblock, &mp->mp_bh[x + 1]);
341 mp->mp_aheight = x + 1;
346 * lookup_metapath - Walk the metadata tree to a specific point
350 * Assumes that the inode's buffer has already been looked up and
351 * hooked onto mp->mp_bh[0] and that the metapath has been initialised
352 * by find_metapath().
354 * If this function encounters part of the tree which has not been
355 * allocated, it returns the current height of the tree at the point
356 * at which it found the unallocated block. Blocks which are found are
357 * added to the mp->mp_bh[] list.
362 static int lookup_metapath(struct gfs2_inode *ip, struct metapath *mp)
364 return __fillup_metapath(ip, mp, 0, ip->i_height - 1);
368 * fillup_metapath - fill up buffers for the metadata path to a specific height
371 * @h: The height to which it should be mapped
373 * Similar to lookup_metapath, but does lookups for a range of heights
375 * Returns: error or the number of buffers filled
378 static int fillup_metapath(struct gfs2_inode *ip, struct metapath *mp, int h)
384 /* find the first buffer we need to look up. */
385 for (x = h - 1; x > 0; x--) {
390 ret = __fillup_metapath(ip, mp, x, h);
393 return mp->mp_aheight - x - 1;
396 static void release_metapath(struct metapath *mp)
400 for (i = 0; i < GFS2_MAX_META_HEIGHT; i++) {
401 if (mp->mp_bh[i] == NULL)
403 brelse(mp->mp_bh[i]);
409 * gfs2_extent_length - Returns length of an extent of blocks
410 * @bh: The metadata block
411 * @ptr: Current position in @bh
412 * @limit: Max extent length to return
413 * @eob: Set to 1 if we hit "end of block"
415 * Returns: The length of the extent (minimum of one block)
418 static inline unsigned int gfs2_extent_length(struct buffer_head *bh, __be64 *ptr, size_t limit, int *eob)
420 const __be64 *end = (__be64 *)(bh->b_data + bh->b_size);
421 const __be64 *first = ptr;
422 u64 d = be64_to_cpu(*ptr);
430 } while(be64_to_cpu(*ptr) == d);
436 typedef const __be64 *(*gfs2_metadata_walker)(
438 const __be64 *start, const __be64 *end,
439 u64 factor, void *data);
441 #define WALK_STOP ((__be64 *)0)
442 #define WALK_NEXT ((__be64 *)1)
444 static int gfs2_walk_metadata(struct inode *inode, sector_t lblock,
445 u64 len, struct metapath *mp, gfs2_metadata_walker walker,
448 struct metapath clone;
449 struct gfs2_inode *ip = GFS2_I(inode);
450 struct gfs2_sbd *sdp = GFS2_SB(inode);
451 const __be64 *start, *end, *ptr;
456 for (hgt = ip->i_height - 1; hgt >= mp->mp_aheight; hgt--)
457 factor *= sdp->sd_inptrs;
462 /* Walk indirect block. */
463 start = metapointer(hgt, mp);
464 end = metaend(hgt, mp);
466 step = (end - start) * factor;
468 end = start + DIV_ROUND_UP_ULL(len, factor);
470 ptr = walker(mp, start, end, factor, data);
471 if (ptr == WALK_STOP)
476 if (ptr != WALK_NEXT) {
478 mp->mp_list[hgt] += ptr - start;
479 goto fill_up_metapath;
483 /* Decrease height of metapath. */
485 clone_metapath(&clone, mp);
488 brelse(mp->mp_bh[hgt]);
489 mp->mp_bh[hgt] = NULL;
493 factor *= sdp->sd_inptrs;
495 /* Advance in metadata tree. */
496 (mp->mp_list[hgt])++;
497 start = metapointer(hgt, mp);
498 end = metaend(hgt, mp);
500 mp->mp_list[hgt] = 0;
507 /* Increase height of metapath. */
509 clone_metapath(&clone, mp);
512 ret = fillup_metapath(ip, mp, ip->i_height - 1);
517 do_div(factor, sdp->sd_inptrs);
518 mp->mp_aheight = hgt + 1;
521 release_metapath(mp);
525 struct gfs2_hole_walker_args {
529 static const __be64 *gfs2_hole_walker(struct metapath *mp,
530 const __be64 *start, const __be64 *end,
531 u64 factor, void *data)
533 struct gfs2_hole_walker_args *args = data;
536 for (ptr = start; ptr < end; ptr++) {
538 args->blocks += (ptr - start) * factor;
539 if (mp->mp_aheight == mp->mp_fheight)
541 return ptr; /* increase height */
544 args->blocks += (end - start) * factor;
549 * gfs2_hole_size - figure out the size of a hole
551 * @lblock: The logical starting block number
552 * @len: How far to look (in blocks)
553 * @mp: The metapath at lblock
554 * @iomap: The iomap to store the hole size in
556 * This function modifies @mp.
558 * Returns: errno on error
560 static int gfs2_hole_size(struct inode *inode, sector_t lblock, u64 len,
561 struct metapath *mp, struct iomap *iomap)
563 struct gfs2_hole_walker_args args = { };
566 ret = gfs2_walk_metadata(inode, lblock, len, mp, gfs2_hole_walker, &args);
568 iomap->length = args.blocks << inode->i_blkbits;
572 static inline __be64 *gfs2_indirect_init(struct metapath *mp,
573 struct gfs2_glock *gl, unsigned int i,
574 unsigned offset, u64 bn)
576 __be64 *ptr = (__be64 *)(mp->mp_bh[i - 1]->b_data +
577 ((i > 1) ? sizeof(struct gfs2_meta_header) :
578 sizeof(struct gfs2_dinode)));
580 BUG_ON(mp->mp_bh[i] != NULL);
581 mp->mp_bh[i] = gfs2_meta_new(gl, bn);
582 gfs2_trans_add_meta(gl, mp->mp_bh[i]);
583 gfs2_metatype_set(mp->mp_bh[i], GFS2_METATYPE_IN, GFS2_FORMAT_IN);
584 gfs2_buffer_clear_tail(mp->mp_bh[i], sizeof(struct gfs2_meta_header));
586 *ptr = cpu_to_be64(bn);
592 ALLOC_GROW_DEPTH = 1,
593 ALLOC_GROW_HEIGHT = 2,
594 /* ALLOC_UNSTUFF = 3, TBD and rather complicated */
598 * gfs2_iomap_alloc - Build a metadata tree of the requested height
599 * @inode: The GFS2 inode
600 * @iomap: The iomap structure
601 * @flags: iomap flags
602 * @mp: The metapath, with proper height information calculated
604 * In this routine we may have to alloc:
605 * i) Indirect blocks to grow the metadata tree height
606 * ii) Indirect blocks to fill in lower part of the metadata tree
609 * This function is called after gfs2_iomap_get, which works out the
610 * total number of blocks which we need via gfs2_alloc_size.
612 * We then do the actual allocation asking for an extent at a time (if
613 * enough contiguous free blocks are available, there will only be one
614 * allocation request per call) and uses the state machine to initialise
615 * the blocks in order.
617 * Right now, this function will allocate at most one indirect block
618 * worth of data -- with a default block size of 4K, that's slightly
619 * less than 2M. If this limitation is ever removed to allow huge
620 * allocations, we would probably still want to limit the iomap size we
621 * return to avoid stalling other tasks during huge writes; the next
622 * iomap iteration would then find the blocks already allocated.
624 * Returns: errno on error
627 static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap,
628 unsigned flags, struct metapath *mp)
630 struct gfs2_inode *ip = GFS2_I(inode);
631 struct gfs2_sbd *sdp = GFS2_SB(inode);
632 struct buffer_head *dibh = mp->mp_bh[0];
634 unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0;
635 size_t dblks = iomap->length >> inode->i_blkbits;
636 const unsigned end_of_metadata = mp->mp_fheight - 1;
638 enum alloc_state state;
642 BUG_ON(mp->mp_aheight < 1);
643 BUG_ON(dibh == NULL);
646 gfs2_trans_add_meta(ip->i_gl, dibh);
648 down_write(&ip->i_rw_mutex);
650 if (mp->mp_fheight == mp->mp_aheight) {
651 /* Bottom indirect block exists */
654 /* Need to allocate indirect blocks */
655 if (mp->mp_fheight == ip->i_height) {
656 /* Writing into existing tree, extend tree down */
657 iblks = mp->mp_fheight - mp->mp_aheight;
658 state = ALLOC_GROW_DEPTH;
660 /* Building up tree height */
661 state = ALLOC_GROW_HEIGHT;
662 iblks = mp->mp_fheight - ip->i_height;
663 branch_start = metapath_branch_start(mp);
664 iblks += (mp->mp_fheight - branch_start);
668 /* start of the second part of the function (state machine) */
670 blks = dblks + iblks;
674 ret = gfs2_alloc_blocks(ip, &bn, &n, 0, NULL);
678 if (state != ALLOC_DATA || gfs2_is_jdata(ip))
679 gfs2_trans_remove_revoke(sdp, bn, n);
681 /* Growing height of tree */
682 case ALLOC_GROW_HEIGHT:
684 ptr = (__be64 *)(dibh->b_data +
685 sizeof(struct gfs2_dinode));
688 for (; i - 1 < mp->mp_fheight - ip->i_height && n > 0;
690 gfs2_indirect_init(mp, ip->i_gl, i, 0, bn++);
691 if (i - 1 == mp->mp_fheight - ip->i_height) {
693 gfs2_buffer_copy_tail(mp->mp_bh[i],
694 sizeof(struct gfs2_meta_header),
695 dibh, sizeof(struct gfs2_dinode));
696 gfs2_buffer_clear_tail(dibh,
697 sizeof(struct gfs2_dinode) +
699 ptr = (__be64 *)(mp->mp_bh[i]->b_data +
700 sizeof(struct gfs2_meta_header));
702 state = ALLOC_GROW_DEPTH;
703 for(i = branch_start; i < mp->mp_fheight; i++) {
704 if (mp->mp_bh[i] == NULL)
706 brelse(mp->mp_bh[i]);
713 /* fall through - To branching from existing tree */
714 case ALLOC_GROW_DEPTH:
715 if (i > 1 && i < mp->mp_fheight)
716 gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[i-1]);
717 for (; i < mp->mp_fheight && n > 0; i++, n--)
718 gfs2_indirect_init(mp, ip->i_gl, i,
719 mp->mp_list[i-1], bn++);
720 if (i == mp->mp_fheight)
724 /* fall through - To tree complete, adding data blocks */
727 BUG_ON(mp->mp_bh[end_of_metadata] == NULL);
728 gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[end_of_metadata]);
730 ptr = metapointer(end_of_metadata, mp);
731 iomap->addr = bn << inode->i_blkbits;
732 iomap->flags |= IOMAP_F_MERGED | IOMAP_F_NEW;
734 *ptr++ = cpu_to_be64(bn++);
737 } while (iomap->addr == IOMAP_NULL_ADDR);
739 iomap->type = IOMAP_MAPPED;
740 iomap->length = (u64)dblks << inode->i_blkbits;
741 ip->i_height = mp->mp_fheight;
742 gfs2_add_inode_blocks(&ip->i_inode, alloced);
743 gfs2_dinode_out(ip, dibh->b_data);
745 up_write(&ip->i_rw_mutex);
749 #define IOMAP_F_GFS2_BOUNDARY IOMAP_F_PRIVATE
752 * gfs2_alloc_size - Compute the maximum allocation size
755 * @size: Requested size in blocks
757 * Compute the maximum size of the next allocation at @mp.
759 * Returns: size in blocks
761 static u64 gfs2_alloc_size(struct inode *inode, struct metapath *mp, u64 size)
763 struct gfs2_inode *ip = GFS2_I(inode);
764 struct gfs2_sbd *sdp = GFS2_SB(inode);
765 const __be64 *first, *ptr, *end;
768 * For writes to stuffed files, this function is called twice via
769 * gfs2_iomap_get, before and after unstuffing. The size we return the
770 * first time needs to be large enough to get the reservation and
771 * allocation sizes right. The size we return the second time must
772 * be exact or else gfs2_iomap_alloc won't do the right thing.
775 if (gfs2_is_stuffed(ip) || mp->mp_fheight != mp->mp_aheight) {
776 unsigned int maxsize = mp->mp_fheight > 1 ?
777 sdp->sd_inptrs : sdp->sd_diptrs;
778 maxsize -= mp->mp_list[mp->mp_fheight - 1];
784 first = metapointer(ip->i_height - 1, mp);
785 end = metaend(ip->i_height - 1, mp);
786 if (end - first > size)
788 for (ptr = first; ptr < end; ptr++) {
796 * gfs2_iomap_get - Map blocks from an inode to disk blocks
798 * @pos: Starting position in bytes
799 * @length: Length to map, in bytes
800 * @flags: iomap flags
801 * @iomap: The iomap structure
806 static int gfs2_iomap_get(struct inode *inode, loff_t pos, loff_t length,
807 unsigned flags, struct iomap *iomap,
810 struct gfs2_inode *ip = GFS2_I(inode);
811 struct gfs2_sbd *sdp = GFS2_SB(inode);
812 loff_t size = i_size_read(inode);
815 sector_t lblock_stop;
819 struct buffer_head *dibh = NULL, *bh;
825 down_read(&ip->i_rw_mutex);
827 ret = gfs2_meta_inode_buffer(ip, &dibh);
832 if (gfs2_is_stuffed(ip)) {
833 if (flags & IOMAP_WRITE) {
834 loff_t max_size = gfs2_max_stuffed_size(ip);
836 if (pos + length > max_size)
838 iomap->length = max_size;
841 if (flags & IOMAP_REPORT) {
847 iomap->length = length;
851 iomap->length = size;
853 iomap->addr = (ip->i_no_addr << inode->i_blkbits) +
854 sizeof(struct gfs2_dinode);
855 iomap->type = IOMAP_INLINE;
856 iomap->inline_data = dibh->b_data + sizeof(struct gfs2_dinode);
861 lblock = pos >> inode->i_blkbits;
862 iomap->offset = lblock << inode->i_blkbits;
863 lblock_stop = (pos + length - 1) >> inode->i_blkbits;
864 len = lblock_stop - lblock + 1;
865 iomap->length = len << inode->i_blkbits;
867 height = ip->i_height;
868 while ((lblock + 1) * sdp->sd_sb.sb_bsize > sdp->sd_heightsize[height])
870 find_metapath(sdp, lblock, mp, height);
871 if (height > ip->i_height || gfs2_is_stuffed(ip))
874 ret = lookup_metapath(ip, mp);
878 if (mp->mp_aheight != ip->i_height)
881 ptr = metapointer(ip->i_height - 1, mp);
885 bh = mp->mp_bh[ip->i_height - 1];
886 len = gfs2_extent_length(bh, ptr, len, &eob);
888 iomap->addr = be64_to_cpu(*ptr) << inode->i_blkbits;
889 iomap->length = len << inode->i_blkbits;
890 iomap->type = IOMAP_MAPPED;
891 iomap->flags |= IOMAP_F_MERGED;
893 iomap->flags |= IOMAP_F_GFS2_BOUNDARY;
896 iomap->bdev = inode->i_sb->s_bdev;
898 up_read(&ip->i_rw_mutex);
902 iomap->addr = IOMAP_NULL_ADDR;
903 iomap->type = IOMAP_HOLE;
904 if (flags & IOMAP_REPORT) {
907 else if (height == ip->i_height)
908 ret = gfs2_hole_size(inode, lblock, len, mp, iomap);
910 iomap->length = size - pos;
911 } else if (flags & IOMAP_WRITE) {
914 if (flags & IOMAP_DIRECT)
915 goto out; /* (see gfs2_file_direct_write) */
917 len = gfs2_alloc_size(inode, mp, len);
918 alloc_size = len << inode->i_blkbits;
919 if (alloc_size < iomap->length)
920 iomap->length = alloc_size;
922 if (pos < size && height == ip->i_height)
923 ret = gfs2_hole_size(inode, lblock, len, mp, iomap);
929 * gfs2_lblk_to_dblk - convert logical block to disk block
930 * @inode: the inode of the file we're mapping
931 * @lblock: the block relative to the start of the file
932 * @dblock: the returned dblock, if no error
934 * This function maps a single block from a file logical block (relative to
935 * the start of the file) to a file system absolute block using iomap.
937 * Returns: the absolute file system block, or an error
939 int gfs2_lblk_to_dblk(struct inode *inode, u32 lblock, u64 *dblock)
941 struct iomap iomap = { };
942 struct metapath mp = { .mp_aheight = 1, };
943 loff_t pos = (loff_t)lblock << inode->i_blkbits;
946 ret = gfs2_iomap_get(inode, pos, i_blocksize(inode), 0, &iomap, &mp);
947 release_metapath(&mp);
949 *dblock = iomap.addr >> inode->i_blkbits;
954 static int gfs2_write_lock(struct inode *inode)
956 struct gfs2_inode *ip = GFS2_I(inode);
957 struct gfs2_sbd *sdp = GFS2_SB(inode);
960 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
961 error = gfs2_glock_nq(&ip->i_gh);
964 if (&ip->i_inode == sdp->sd_rindex) {
965 struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
967 error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE,
968 GL_NOCACHE, &m_ip->i_gh);
975 gfs2_glock_dq(&ip->i_gh);
977 gfs2_holder_uninit(&ip->i_gh);
981 static void gfs2_write_unlock(struct inode *inode)
983 struct gfs2_inode *ip = GFS2_I(inode);
984 struct gfs2_sbd *sdp = GFS2_SB(inode);
986 if (&ip->i_inode == sdp->sd_rindex) {
987 struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
989 gfs2_glock_dq_uninit(&m_ip->i_gh);
991 gfs2_glock_dq_uninit(&ip->i_gh);
994 static int gfs2_iomap_page_prepare(struct inode *inode, loff_t pos,
995 unsigned len, struct iomap *iomap)
997 struct gfs2_sbd *sdp = GFS2_SB(inode);
999 return gfs2_trans_begin(sdp, RES_DINODE + (len >> inode->i_blkbits), 0);
1002 static void gfs2_iomap_page_done(struct inode *inode, loff_t pos,
1003 unsigned copied, struct page *page,
1004 struct iomap *iomap)
1006 struct gfs2_inode *ip = GFS2_I(inode);
1007 struct gfs2_sbd *sdp = GFS2_SB(inode);
1009 if (page && !gfs2_is_stuffed(ip))
1010 gfs2_page_add_databufs(ip, page, offset_in_page(pos), copied);
1011 gfs2_trans_end(sdp);
1014 static const struct iomap_page_ops gfs2_iomap_page_ops = {
1015 .page_prepare = gfs2_iomap_page_prepare,
1016 .page_done = gfs2_iomap_page_done,
1019 static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos,
1020 loff_t length, unsigned flags,
1021 struct iomap *iomap,
1022 struct metapath *mp)
1024 struct gfs2_inode *ip = GFS2_I(inode);
1025 struct gfs2_sbd *sdp = GFS2_SB(inode);
1026 unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
1027 bool unstuff, alloc_required;
1030 ret = gfs2_write_lock(inode);
1034 unstuff = gfs2_is_stuffed(ip) &&
1035 pos + length > gfs2_max_stuffed_size(ip);
1037 ret = gfs2_iomap_get(inode, pos, length, flags, iomap, mp);
1041 alloc_required = unstuff || iomap->type == IOMAP_HOLE;
1043 if (alloc_required || gfs2_is_jdata(ip))
1044 gfs2_write_calc_reserv(ip, iomap->length, &data_blocks,
1047 if (alloc_required) {
1048 struct gfs2_alloc_parms ap = {
1049 .target = data_blocks + ind_blocks
1052 ret = gfs2_quota_lock_check(ip, &ap);
1056 ret = gfs2_inplace_reserve(ip, &ap);
1061 rblocks = RES_DINODE + ind_blocks;
1062 if (gfs2_is_jdata(ip))
1063 rblocks += data_blocks;
1064 if (ind_blocks || data_blocks)
1065 rblocks += RES_STATFS + RES_QUOTA;
1066 if (inode == sdp->sd_rindex)
1067 rblocks += 2 * RES_STATFS;
1069 rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
1071 if (unstuff || iomap->type == IOMAP_HOLE) {
1072 struct gfs2_trans *tr;
1074 ret = gfs2_trans_begin(sdp, rblocks,
1075 iomap->length >> inode->i_blkbits);
1077 goto out_trans_fail;
1080 ret = gfs2_unstuff_dinode(ip, NULL);
1083 release_metapath(mp);
1084 ret = gfs2_iomap_get(inode, iomap->offset,
1085 iomap->length, flags, iomap, mp);
1090 if (iomap->type == IOMAP_HOLE) {
1091 ret = gfs2_iomap_alloc(inode, iomap, flags, mp);
1093 gfs2_trans_end(sdp);
1094 gfs2_inplace_release(ip);
1095 punch_hole(ip, iomap->offset, iomap->length);
1100 tr = current->journal_info;
1101 if (tr->tr_num_buf_new)
1102 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
1104 gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[0]);
1106 gfs2_trans_end(sdp);
1109 if (gfs2_is_stuffed(ip) || gfs2_is_jdata(ip))
1110 iomap->page_ops = &gfs2_iomap_page_ops;
1114 gfs2_trans_end(sdp);
1117 gfs2_inplace_release(ip);
1120 gfs2_quota_unlock(ip);
1122 gfs2_write_unlock(inode);
1126 static int gfs2_iomap_begin(struct inode *inode, loff_t pos, loff_t length,
1127 unsigned flags, struct iomap *iomap)
1129 struct gfs2_inode *ip = GFS2_I(inode);
1130 struct metapath mp = { .mp_aheight = 1, };
1133 iomap->flags |= IOMAP_F_BUFFER_HEAD;
1135 trace_gfs2_iomap_start(ip, pos, length, flags);
1136 if ((flags & IOMAP_WRITE) && !(flags & IOMAP_DIRECT)) {
1137 ret = gfs2_iomap_begin_write(inode, pos, length, flags, iomap, &mp);
1139 ret = gfs2_iomap_get(inode, pos, length, flags, iomap, &mp);
1142 * Silently fall back to buffered I/O for stuffed files or if
1143 * we've hot a hole (see gfs2_file_direct_write).
1145 if ((flags & IOMAP_WRITE) && (flags & IOMAP_DIRECT) &&
1146 iomap->type != IOMAP_MAPPED)
1149 release_metapath(&mp);
1150 trace_gfs2_iomap_end(ip, iomap, ret);
1154 static int gfs2_iomap_end(struct inode *inode, loff_t pos, loff_t length,
1155 ssize_t written, unsigned flags, struct iomap *iomap)
1157 struct gfs2_inode *ip = GFS2_I(inode);
1158 struct gfs2_sbd *sdp = GFS2_SB(inode);
1160 if ((flags & (IOMAP_WRITE | IOMAP_DIRECT)) != IOMAP_WRITE)
1163 if (!gfs2_is_stuffed(ip))
1164 gfs2_ordered_add_inode(ip);
1166 if (inode == sdp->sd_rindex)
1167 adjust_fs_space(inode);
1169 gfs2_inplace_release(ip);
1171 if (length != written && (iomap->flags & IOMAP_F_NEW)) {
1172 /* Deallocate blocks that were just allocated. */
1173 loff_t blockmask = i_blocksize(inode) - 1;
1174 loff_t end = (pos + length) & ~blockmask;
1176 pos = (pos + written + blockmask) & ~blockmask;
1178 truncate_pagecache_range(inode, pos, end - 1);
1179 punch_hole(ip, pos, end - pos);
1183 if (ip->i_qadata && ip->i_qadata->qa_qd_num)
1184 gfs2_quota_unlock(ip);
1185 gfs2_write_unlock(inode);
1191 const struct iomap_ops gfs2_iomap_ops = {
1192 .iomap_begin = gfs2_iomap_begin,
1193 .iomap_end = gfs2_iomap_end,
1197 * gfs2_block_map - Map one or more blocks of an inode to a disk block
1199 * @lblock: The logical block number
1200 * @bh_map: The bh to be mapped
1201 * @create: True if its ok to alloc blocks to satify the request
1203 * The size of the requested mapping is defined in bh_map->b_size.
1205 * Clears buffer_mapped(bh_map) and leaves bh_map->b_size unchanged
1206 * when @lblock is not mapped. Sets buffer_mapped(bh_map) and
1207 * bh_map->b_size to indicate the size of the mapping when @lblock and
1208 * successive blocks are mapped, up to the requested size.
1210 * Sets buffer_boundary() if a read of metadata will be required
1211 * before the next block can be mapped. Sets buffer_new() if new
1212 * blocks were allocated.
1217 int gfs2_block_map(struct inode *inode, sector_t lblock,
1218 struct buffer_head *bh_map, int create)
1220 struct gfs2_inode *ip = GFS2_I(inode);
1221 loff_t pos = (loff_t)lblock << inode->i_blkbits;
1222 loff_t length = bh_map->b_size;
1223 struct metapath mp = { .mp_aheight = 1, };
1224 struct iomap iomap = { };
1227 clear_buffer_mapped(bh_map);
1228 clear_buffer_new(bh_map);
1229 clear_buffer_boundary(bh_map);
1230 trace_gfs2_bmap(ip, bh_map, lblock, create, 1);
1233 ret = gfs2_iomap_get(inode, pos, length, IOMAP_WRITE, &iomap, &mp);
1234 if (!ret && iomap.type == IOMAP_HOLE)
1235 ret = gfs2_iomap_alloc(inode, &iomap, IOMAP_WRITE, &mp);
1236 release_metapath(&mp);
1238 ret = gfs2_iomap_get(inode, pos, length, 0, &iomap, &mp);
1239 release_metapath(&mp);
1244 if (iomap.length > bh_map->b_size) {
1245 iomap.length = bh_map->b_size;
1246 iomap.flags &= ~IOMAP_F_GFS2_BOUNDARY;
1248 if (iomap.addr != IOMAP_NULL_ADDR)
1249 map_bh(bh_map, inode->i_sb, iomap.addr >> inode->i_blkbits);
1250 bh_map->b_size = iomap.length;
1251 if (iomap.flags & IOMAP_F_GFS2_BOUNDARY)
1252 set_buffer_boundary(bh_map);
1253 if (iomap.flags & IOMAP_F_NEW)
1254 set_buffer_new(bh_map);
1257 trace_gfs2_bmap(ip, bh_map, lblock, create, ret);
1262 * Deprecated: do not use in new code
1264 int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
1266 struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 };
1274 bh.b_size = BIT(inode->i_blkbits + (create ? 0 : 5));
1275 ret = gfs2_block_map(inode, lblock, &bh, create);
1276 *extlen = bh.b_size >> inode->i_blkbits;
1277 *dblock = bh.b_blocknr;
1278 if (buffer_new(&bh))
1286 * gfs2_block_zero_range - Deal with zeroing out data
1288 * This is partly borrowed from ext3.
1290 static int gfs2_block_zero_range(struct inode *inode, loff_t from,
1291 unsigned int length)
1293 struct address_space *mapping = inode->i_mapping;
1294 struct gfs2_inode *ip = GFS2_I(inode);
1295 unsigned long index = from >> PAGE_SHIFT;
1296 unsigned offset = from & (PAGE_SIZE-1);
1297 unsigned blocksize, iblock, pos;
1298 struct buffer_head *bh;
1302 page = find_or_create_page(mapping, index, GFP_NOFS);
1306 blocksize = inode->i_sb->s_blocksize;
1307 iblock = index << (PAGE_SHIFT - inode->i_sb->s_blocksize_bits);
1309 if (!page_has_buffers(page))
1310 create_empty_buffers(page, blocksize, 0);
1312 /* Find the buffer that contains "offset" */
1313 bh = page_buffers(page);
1315 while (offset >= pos) {
1316 bh = bh->b_this_page;
1323 if (!buffer_mapped(bh)) {
1324 gfs2_block_map(inode, iblock, bh, 0);
1325 /* unmapped? It's a hole - nothing to do */
1326 if (!buffer_mapped(bh))
1330 /* Ok, it's mapped. Make sure it's up-to-date */
1331 if (PageUptodate(page))
1332 set_buffer_uptodate(bh);
1334 if (!buffer_uptodate(bh)) {
1336 ll_rw_block(REQ_OP_READ, 0, 1, &bh);
1338 /* Uhhuh. Read error. Complain and punt. */
1339 if (!buffer_uptodate(bh))
1344 if (gfs2_is_jdata(ip))
1345 gfs2_trans_add_data(ip->i_gl, bh);
1347 gfs2_ordered_add_inode(ip);
1349 zero_user(page, offset, length);
1350 mark_buffer_dirty(bh);
1357 #define GFS2_JTRUNC_REVOKES 8192
1360 * gfs2_journaled_truncate - Wrapper for truncate_pagecache for jdata files
1361 * @inode: The inode being truncated
1362 * @oldsize: The original (larger) size
1363 * @newsize: The new smaller size
1365 * With jdata files, we have to journal a revoke for each block which is
1366 * truncated. As a result, we need to split this into separate transactions
1367 * if the number of pages being truncated gets too large.
1370 static int gfs2_journaled_truncate(struct inode *inode, u64 oldsize, u64 newsize)
1372 struct gfs2_sbd *sdp = GFS2_SB(inode);
1373 u64 max_chunk = GFS2_JTRUNC_REVOKES * sdp->sd_vfs->s_blocksize;
1377 while (oldsize != newsize) {
1378 struct gfs2_trans *tr;
1381 chunk = oldsize - newsize;
1382 if (chunk > max_chunk)
1385 offs = oldsize & ~PAGE_MASK;
1386 if (offs && chunk > PAGE_SIZE)
1387 chunk = offs + ((chunk - offs) & PAGE_MASK);
1389 truncate_pagecache(inode, oldsize - chunk);
1392 tr = current->journal_info;
1393 if (!test_bit(TR_TOUCHED, &tr->tr_flags))
1396 gfs2_trans_end(sdp);
1397 error = gfs2_trans_begin(sdp, RES_DINODE, GFS2_JTRUNC_REVOKES);
1405 static int trunc_start(struct inode *inode, u64 newsize)
1407 struct gfs2_inode *ip = GFS2_I(inode);
1408 struct gfs2_sbd *sdp = GFS2_SB(inode);
1409 struct buffer_head *dibh = NULL;
1410 int journaled = gfs2_is_jdata(ip);
1411 u64 oldsize = inode->i_size;
1415 error = gfs2_trans_begin(sdp, RES_DINODE + RES_JDATA, GFS2_JTRUNC_REVOKES);
1417 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1421 error = gfs2_meta_inode_buffer(ip, &dibh);
1425 gfs2_trans_add_meta(ip->i_gl, dibh);
1427 if (gfs2_is_stuffed(ip)) {
1428 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + newsize);
1430 unsigned int blocksize = i_blocksize(inode);
1431 unsigned int offs = newsize & (blocksize - 1);
1433 error = gfs2_block_zero_range(inode, newsize,
1438 ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG;
1441 i_size_write(inode, newsize);
1442 ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode);
1443 gfs2_dinode_out(ip, dibh->b_data);
1446 error = gfs2_journaled_truncate(inode, oldsize, newsize);
1448 truncate_pagecache(inode, newsize);
1452 if (current->journal_info)
1453 gfs2_trans_end(sdp);
1457 int gfs2_iomap_get_alloc(struct inode *inode, loff_t pos, loff_t length,
1458 struct iomap *iomap)
1460 struct metapath mp = { .mp_aheight = 1, };
1463 ret = gfs2_iomap_get(inode, pos, length, IOMAP_WRITE, iomap, &mp);
1464 if (!ret && iomap->type == IOMAP_HOLE)
1465 ret = gfs2_iomap_alloc(inode, iomap, IOMAP_WRITE, &mp);
1466 release_metapath(&mp);
1471 * sweep_bh_for_rgrps - find an rgrp in a meta buffer and free blocks therein
1473 * @rg_gh: holder of resource group glock
1474 * @bh: buffer head to sweep
1475 * @start: starting point in bh
1476 * @end: end point in bh
1477 * @meta: true if bh points to metadata (rather than data)
1478 * @btotal: place to keep count of total blocks freed
1480 * We sweep a metadata buffer (provided by the metapath) for blocks we need to
1481 * free, and free them all. However, we do it one rgrp at a time. If this
1482 * block has references to multiple rgrps, we break it into individual
1483 * transactions. This allows other processes to use the rgrps while we're
1484 * focused on a single one, for better concurrency / performance.
1485 * At every transaction boundary, we rewrite the inode into the journal.
1486 * That way the bitmaps are kept consistent with the inode and we can recover
1487 * if we're interrupted by power-outages.
1489 * Returns: 0, or return code if an error occurred.
1490 * *btotal has the total number of blocks freed
1492 static int sweep_bh_for_rgrps(struct gfs2_inode *ip, struct gfs2_holder *rd_gh,
1493 struct buffer_head *bh, __be64 *start, __be64 *end,
1494 bool meta, u32 *btotal)
1496 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1497 struct gfs2_rgrpd *rgd;
1498 struct gfs2_trans *tr;
1500 int blks_outside_rgrp;
1501 u64 bn, bstart, isize_blks;
1502 s64 blen; /* needs to be s64 or gfs2_add_inode_blocks breaks */
1504 bool buf_in_tr = false; /* buffer was added to transaction */
1508 if (gfs2_holder_initialized(rd_gh)) {
1509 rgd = gfs2_glock2rgrp(rd_gh->gh_gl);
1510 gfs2_assert_withdraw(sdp,
1511 gfs2_glock_is_locked_by_me(rd_gh->gh_gl));
1513 blks_outside_rgrp = 0;
1517 for (p = start; p < end; p++) {
1520 bn = be64_to_cpu(*p);
1523 if (!rgrp_contains_block(rgd, bn)) {
1524 blks_outside_rgrp++;
1528 rgd = gfs2_blk2rgrpd(sdp, bn, true);
1529 if (unlikely(!rgd)) {
1533 ret = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE,
1538 /* Must be done with the rgrp glock held: */
1539 if (gfs2_rs_active(&ip->i_res) &&
1540 rgd == ip->i_res.rs_rbm.rgd)
1541 gfs2_rs_deltree(&ip->i_res);
1544 /* The size of our transactions will be unknown until we
1545 actually process all the metadata blocks that relate to
1546 the rgrp. So we estimate. We know it can't be more than
1547 the dinode's i_blocks and we don't want to exceed the
1548 journal flush threshold, sd_log_thresh2. */
1549 if (current->journal_info == NULL) {
1550 unsigned int jblocks_rqsted, revokes;
1552 jblocks_rqsted = rgd->rd_length + RES_DINODE +
1554 isize_blks = gfs2_get_inode_blocks(&ip->i_inode);
1555 if (isize_blks > atomic_read(&sdp->sd_log_thresh2))
1557 atomic_read(&sdp->sd_log_thresh2);
1559 jblocks_rqsted += isize_blks;
1560 revokes = jblocks_rqsted;
1562 revokes += end - start;
1563 else if (ip->i_depth)
1564 revokes += sdp->sd_inptrs;
1565 ret = gfs2_trans_begin(sdp, jblocks_rqsted, revokes);
1568 down_write(&ip->i_rw_mutex);
1570 /* check if we will exceed the transaction blocks requested */
1571 tr = current->journal_info;
1572 if (tr->tr_num_buf_new + RES_STATFS +
1573 RES_QUOTA >= atomic_read(&sdp->sd_log_thresh2)) {
1574 /* We set blks_outside_rgrp to ensure the loop will
1575 be repeated for the same rgrp, but with a new
1577 blks_outside_rgrp++;
1578 /* This next part is tricky. If the buffer was added
1579 to the transaction, we've already set some block
1580 pointers to 0, so we better follow through and free
1581 them, or we will introduce corruption (so break).
1582 This may be impossible, or at least rare, but I
1583 decided to cover the case regardless.
1585 If the buffer was not added to the transaction
1586 (this call), doing so would exceed our transaction
1587 size, so we need to end the transaction and start a
1588 new one (so goto). */
1595 gfs2_trans_add_meta(ip->i_gl, bh);
1598 if (bstart + blen == bn) {
1603 __gfs2_free_blocks(ip, rgd, bstart, (u32)blen, meta);
1605 gfs2_add_inode_blocks(&ip->i_inode, -blen);
1611 __gfs2_free_blocks(ip, rgd, bstart, (u32)blen, meta);
1613 gfs2_add_inode_blocks(&ip->i_inode, -blen);
1616 if (!ret && blks_outside_rgrp) { /* If buffer still has non-zero blocks
1617 outside the rgrp we just processed,
1618 do it all over again. */
1619 if (current->journal_info) {
1620 struct buffer_head *dibh;
1622 ret = gfs2_meta_inode_buffer(ip, &dibh);
1626 /* Every transaction boundary, we rewrite the dinode
1627 to keep its di_blocks current in case of failure. */
1628 ip->i_inode.i_mtime = ip->i_inode.i_ctime =
1629 current_time(&ip->i_inode);
1630 gfs2_trans_add_meta(ip->i_gl, dibh);
1631 gfs2_dinode_out(ip, dibh->b_data);
1633 up_write(&ip->i_rw_mutex);
1634 gfs2_trans_end(sdp);
1636 gfs2_glock_dq_uninit(rd_gh);
1644 static bool mp_eq_to_hgt(struct metapath *mp, __u16 *list, unsigned int h)
1646 if (memcmp(mp->mp_list, list, h * sizeof(mp->mp_list[0])))
1652 * find_nonnull_ptr - find a non-null pointer given a metapath and height
1653 * @mp: starting metapath
1654 * @h: desired height to search
1656 * Assumes the metapath is valid (with buffers) out to height h.
1657 * Returns: true if a non-null pointer was found in the metapath buffer
1658 * false if all remaining pointers are NULL in the buffer
1660 static bool find_nonnull_ptr(struct gfs2_sbd *sdp, struct metapath *mp,
1662 __u16 *end_list, unsigned int end_aligned)
1664 struct buffer_head *bh = mp->mp_bh[h];
1665 __be64 *first, *ptr, *end;
1667 first = metaptr1(h, mp);
1668 ptr = first + mp->mp_list[h];
1669 end = (__be64 *)(bh->b_data + bh->b_size);
1670 if (end_list && mp_eq_to_hgt(mp, end_list, h)) {
1671 bool keep_end = h < end_aligned;
1672 end = first + end_list[h] + keep_end;
1676 if (*ptr) { /* if we have a non-null pointer */
1677 mp->mp_list[h] = ptr - first;
1679 if (h < GFS2_MAX_META_HEIGHT)
1688 enum dealloc_states {
1689 DEALLOC_MP_FULL = 0, /* Strip a metapath with all buffers read in */
1690 DEALLOC_MP_LOWER = 1, /* lower the metapath strip height */
1691 DEALLOC_FILL_MP = 2, /* Fill in the metapath to the given height. */
1692 DEALLOC_DONE = 3, /* process complete */
1696 metapointer_range(struct metapath *mp, int height,
1697 __u16 *start_list, unsigned int start_aligned,
1698 __u16 *end_list, unsigned int end_aligned,
1699 __be64 **start, __be64 **end)
1701 struct buffer_head *bh = mp->mp_bh[height];
1704 first = metaptr1(height, mp);
1706 if (mp_eq_to_hgt(mp, start_list, height)) {
1707 bool keep_start = height < start_aligned;
1708 *start = first + start_list[height] + keep_start;
1710 *end = (__be64 *)(bh->b_data + bh->b_size);
1711 if (end_list && mp_eq_to_hgt(mp, end_list, height)) {
1712 bool keep_end = height < end_aligned;
1713 *end = first + end_list[height] + keep_end;
1717 static inline bool walk_done(struct gfs2_sbd *sdp,
1718 struct metapath *mp, int height,
1719 __u16 *end_list, unsigned int end_aligned)
1724 bool keep_end = height < end_aligned;
1725 if (!mp_eq_to_hgt(mp, end_list, height))
1727 end = end_list[height] + keep_end;
1729 end = (height > 0) ? sdp->sd_inptrs : sdp->sd_diptrs;
1730 return mp->mp_list[height] >= end;
1734 * punch_hole - deallocate blocks in a file
1735 * @ip: inode to truncate
1736 * @offset: the start of the hole
1737 * @length: the size of the hole (or 0 for truncate)
1739 * Punch a hole into a file or truncate a file at a given position. This
1740 * function operates in whole blocks (@offset and @length are rounded
1741 * accordingly); partially filled blocks must be cleared otherwise.
1743 * This function works from the bottom up, and from the right to the left. In
1744 * other words, it strips off the highest layer (data) before stripping any of
1745 * the metadata. Doing it this way is best in case the operation is interrupted
1746 * by power failure, etc. The dinode is rewritten in every transaction to
1747 * guarantee integrity.
1749 static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length)
1751 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1752 u64 maxsize = sdp->sd_heightsize[ip->i_height];
1753 struct metapath mp = {};
1754 struct buffer_head *dibh, *bh;
1755 struct gfs2_holder rd_gh;
1756 unsigned int bsize_shift = sdp->sd_sb.sb_bsize_shift;
1757 u64 lblock = (offset + (1 << bsize_shift) - 1) >> bsize_shift;
1758 __u16 start_list[GFS2_MAX_META_HEIGHT];
1759 __u16 __end_list[GFS2_MAX_META_HEIGHT], *end_list = NULL;
1760 unsigned int start_aligned, uninitialized_var(end_aligned);
1761 unsigned int strip_h = ip->i_height - 1;
1764 int mp_h; /* metapath buffers are read in to this height */
1766 __be64 *start, *end;
1768 if (offset >= maxsize) {
1770 * The starting point lies beyond the allocated meta-data;
1771 * there are no blocks do deallocate.
1777 * The start position of the hole is defined by lblock, start_list, and
1778 * start_aligned. The end position of the hole is defined by lend,
1779 * end_list, and end_aligned.
1781 * start_aligned and end_aligned define down to which height the start
1782 * and end positions are aligned to the metadata tree (i.e., the
1783 * position is a multiple of the metadata granularity at the height
1784 * above). This determines at which heights additional meta pointers
1785 * needs to be preserved for the remaining data.
1789 u64 end_offset = offset + length;
1793 * Clip the end at the maximum file size for the given height:
1794 * that's how far the metadata goes; files bigger than that
1795 * will have additional layers of indirection.
1797 if (end_offset > maxsize)
1798 end_offset = maxsize;
1799 lend = end_offset >> bsize_shift;
1804 find_metapath(sdp, lend, &mp, ip->i_height);
1805 end_list = __end_list;
1806 memcpy(end_list, mp.mp_list, sizeof(mp.mp_list));
1808 for (mp_h = ip->i_height - 1; mp_h > 0; mp_h--) {
1815 find_metapath(sdp, lblock, &mp, ip->i_height);
1816 memcpy(start_list, mp.mp_list, sizeof(start_list));
1818 for (mp_h = ip->i_height - 1; mp_h > 0; mp_h--) {
1819 if (start_list[mp_h])
1822 start_aligned = mp_h;
1824 ret = gfs2_meta_inode_buffer(ip, &dibh);
1829 ret = lookup_metapath(ip, &mp);
1833 /* issue read-ahead on metadata */
1834 for (mp_h = 0; mp_h < mp.mp_aheight - 1; mp_h++) {
1835 metapointer_range(&mp, mp_h, start_list, start_aligned,
1836 end_list, end_aligned, &start, &end);
1837 gfs2_metapath_ra(ip->i_gl, start, end);
1840 if (mp.mp_aheight == ip->i_height)
1841 state = DEALLOC_MP_FULL; /* We have a complete metapath */
1843 state = DEALLOC_FILL_MP; /* deal with partial metapath */
1845 ret = gfs2_rindex_update(sdp);
1849 ret = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1852 gfs2_holder_mark_uninitialized(&rd_gh);
1856 while (state != DEALLOC_DONE) {
1858 /* Truncate a full metapath at the given strip height.
1859 * Note that strip_h == mp_h in order to be in this state. */
1860 case DEALLOC_MP_FULL:
1861 bh = mp.mp_bh[mp_h];
1862 gfs2_assert_withdraw(sdp, bh);
1863 if (gfs2_assert_withdraw(sdp,
1864 prev_bnr != bh->b_blocknr)) {
1865 printk(KERN_EMERG "GFS2: fsid=%s:inode %llu, "
1866 "block:%llu, i_h:%u, s_h:%u, mp_h:%u\n",
1868 (unsigned long long)ip->i_no_addr,
1869 prev_bnr, ip->i_height, strip_h, mp_h);
1871 prev_bnr = bh->b_blocknr;
1873 if (gfs2_metatype_check(sdp, bh,
1874 (mp_h ? GFS2_METATYPE_IN :
1875 GFS2_METATYPE_DI))) {
1881 * Below, passing end_aligned as 0 gives us the
1882 * metapointer range excluding the end point: the end
1883 * point is the first metapath we must not deallocate!
1886 metapointer_range(&mp, mp_h, start_list, start_aligned,
1887 end_list, 0 /* end_aligned */,
1889 ret = sweep_bh_for_rgrps(ip, &rd_gh, mp.mp_bh[mp_h],
1891 mp_h != ip->i_height - 1,
1894 /* If we hit an error or just swept dinode buffer,
1897 state = DEALLOC_DONE;
1900 state = DEALLOC_MP_LOWER;
1903 /* lower the metapath strip height */
1904 case DEALLOC_MP_LOWER:
1905 /* We're done with the current buffer, so release it,
1906 unless it's the dinode buffer. Then back up to the
1907 previous pointer. */
1909 brelse(mp.mp_bh[mp_h]);
1910 mp.mp_bh[mp_h] = NULL;
1912 /* If we can't get any lower in height, we've stripped
1913 off all we can. Next step is to back up and start
1914 stripping the previous level of metadata. */
1917 memcpy(mp.mp_list, start_list, sizeof(start_list));
1919 state = DEALLOC_FILL_MP;
1922 mp.mp_list[mp_h] = 0;
1923 mp_h--; /* search one metadata height down */
1925 if (walk_done(sdp, &mp, mp_h, end_list, end_aligned))
1927 /* Here we've found a part of the metapath that is not
1928 * allocated. We need to search at that height for the
1929 * next non-null pointer. */
1930 if (find_nonnull_ptr(sdp, &mp, mp_h, end_list, end_aligned)) {
1931 state = DEALLOC_FILL_MP;
1934 /* No more non-null pointers at this height. Back up
1935 to the previous height and try again. */
1936 break; /* loop around in the same state */
1938 /* Fill the metapath with buffers to the given height. */
1939 case DEALLOC_FILL_MP:
1940 /* Fill the buffers out to the current height. */
1941 ret = fillup_metapath(ip, &mp, mp_h);
1945 /* On the first pass, issue read-ahead on metadata. */
1946 if (mp.mp_aheight > 1 && strip_h == ip->i_height - 1) {
1947 unsigned int height = mp.mp_aheight - 1;
1949 /* No read-ahead for data blocks. */
1950 if (mp.mp_aheight - 1 == strip_h)
1953 for (; height >= mp.mp_aheight - ret; height--) {
1954 metapointer_range(&mp, height,
1955 start_list, start_aligned,
1956 end_list, end_aligned,
1958 gfs2_metapath_ra(ip->i_gl, start, end);
1962 /* If buffers found for the entire strip height */
1963 if (mp.mp_aheight - 1 == strip_h) {
1964 state = DEALLOC_MP_FULL;
1967 if (mp.mp_aheight < ip->i_height) /* We have a partial height */
1968 mp_h = mp.mp_aheight - 1;
1970 /* If we find a non-null block pointer, crawl a bit
1971 higher up in the metapath and try again, otherwise
1972 we need to look lower for a new starting point. */
1973 if (find_nonnull_ptr(sdp, &mp, mp_h, end_list, end_aligned))
1976 state = DEALLOC_MP_LOWER;
1982 if (current->journal_info == NULL) {
1983 ret = gfs2_trans_begin(sdp, RES_DINODE + RES_STATFS +
1987 down_write(&ip->i_rw_mutex);
1989 gfs2_statfs_change(sdp, 0, +btotal, 0);
1990 gfs2_quota_change(ip, -(s64)btotal, ip->i_inode.i_uid,
1992 ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode);
1993 gfs2_trans_add_meta(ip->i_gl, dibh);
1994 gfs2_dinode_out(ip, dibh->b_data);
1995 up_write(&ip->i_rw_mutex);
1996 gfs2_trans_end(sdp);
2000 if (gfs2_holder_initialized(&rd_gh))
2001 gfs2_glock_dq_uninit(&rd_gh);
2002 if (current->journal_info) {
2003 up_write(&ip->i_rw_mutex);
2004 gfs2_trans_end(sdp);
2007 gfs2_quota_unhold(ip);
2009 release_metapath(&mp);
2013 static int trunc_end(struct gfs2_inode *ip)
2015 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2016 struct buffer_head *dibh;
2019 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
2023 down_write(&ip->i_rw_mutex);
2025 error = gfs2_meta_inode_buffer(ip, &dibh);
2029 if (!i_size_read(&ip->i_inode)) {
2031 ip->i_goal = ip->i_no_addr;
2032 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
2033 gfs2_ordered_del_inode(ip);
2035 ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode);
2036 ip->i_diskflags &= ~GFS2_DIF_TRUNC_IN_PROG;
2038 gfs2_trans_add_meta(ip->i_gl, dibh);
2039 gfs2_dinode_out(ip, dibh->b_data);
2043 up_write(&ip->i_rw_mutex);
2044 gfs2_trans_end(sdp);
2049 * do_shrink - make a file smaller
2051 * @newsize: the size to make the file
2053 * Called with an exclusive lock on @inode. The @size must
2054 * be equal to or smaller than the current inode size.
2059 static int do_shrink(struct inode *inode, u64 newsize)
2061 struct gfs2_inode *ip = GFS2_I(inode);
2064 error = trunc_start(inode, newsize);
2067 if (gfs2_is_stuffed(ip))
2070 error = punch_hole(ip, newsize, 0);
2072 error = trunc_end(ip);
2077 void gfs2_trim_blocks(struct inode *inode)
2081 ret = do_shrink(inode, inode->i_size);
2086 * do_grow - Touch and update inode size
2088 * @size: The new size
2090 * This function updates the timestamps on the inode and
2091 * may also increase the size of the inode. This function
2092 * must not be called with @size any smaller than the current
2095 * Although it is not strictly required to unstuff files here,
2096 * earlier versions of GFS2 have a bug in the stuffed file reading
2097 * code which will result in a buffer overrun if the size is larger
2098 * than the max stuffed file size. In order to prevent this from
2099 * occurring, such files are unstuffed, but in other cases we can
2100 * just update the inode size directly.
2102 * Returns: 0 on success, or -ve on error
2105 static int do_grow(struct inode *inode, u64 size)
2107 struct gfs2_inode *ip = GFS2_I(inode);
2108 struct gfs2_sbd *sdp = GFS2_SB(inode);
2109 struct gfs2_alloc_parms ap = { .target = 1, };
2110 struct buffer_head *dibh;
2114 if (gfs2_is_stuffed(ip) && size > gfs2_max_stuffed_size(ip)) {
2115 error = gfs2_quota_lock_check(ip, &ap);
2119 error = gfs2_inplace_reserve(ip, &ap);
2121 goto do_grow_qunlock;
2125 error = gfs2_trans_begin(sdp, RES_DINODE + RES_STATFS + RES_RG_BIT +
2127 gfs2_is_jdata(ip) ? RES_JDATA : 0) +
2128 (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF ?
2131 goto do_grow_release;
2134 error = gfs2_unstuff_dinode(ip, NULL);
2139 error = gfs2_meta_inode_buffer(ip, &dibh);
2143 i_size_write(inode, size);
2144 ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode);
2145 gfs2_trans_add_meta(ip->i_gl, dibh);
2146 gfs2_dinode_out(ip, dibh->b_data);
2150 gfs2_trans_end(sdp);
2153 gfs2_inplace_release(ip);
2155 gfs2_quota_unlock(ip);
2161 * gfs2_setattr_size - make a file a given size
2163 * @newsize: the size to make the file
2165 * The file size can grow, shrink, or stay the same size. This
2166 * is called holding i_rwsem and an exclusive glock on the inode
2172 int gfs2_setattr_size(struct inode *inode, u64 newsize)
2174 struct gfs2_inode *ip = GFS2_I(inode);
2177 BUG_ON(!S_ISREG(inode->i_mode));
2179 ret = inode_newsize_ok(inode, newsize);
2183 inode_dio_wait(inode);
2185 ret = gfs2_rsqa_alloc(ip);
2189 if (newsize >= inode->i_size) {
2190 ret = do_grow(inode, newsize);
2194 ret = do_shrink(inode, newsize);
2196 gfs2_rsqa_delete(ip, NULL);
2200 int gfs2_truncatei_resume(struct gfs2_inode *ip)
2203 error = punch_hole(ip, i_size_read(&ip->i_inode), 0);
2205 error = trunc_end(ip);
2209 int gfs2_file_dealloc(struct gfs2_inode *ip)
2211 return punch_hole(ip, 0, 0);
2215 * gfs2_free_journal_extents - Free cached journal bmap info
2220 void gfs2_free_journal_extents(struct gfs2_jdesc *jd)
2222 struct gfs2_journal_extent *jext;
2224 while(!list_empty(&jd->extent_list)) {
2225 jext = list_entry(jd->extent_list.next, struct gfs2_journal_extent, list);
2226 list_del(&jext->list);
2232 * gfs2_add_jextent - Add or merge a new extent to extent cache
2233 * @jd: The journal descriptor
2234 * @lblock: The logical block at start of new extent
2235 * @dblock: The physical block at start of new extent
2236 * @blocks: Size of extent in fs blocks
2238 * Returns: 0 on success or -ENOMEM
2241 static int gfs2_add_jextent(struct gfs2_jdesc *jd, u64 lblock, u64 dblock, u64 blocks)
2243 struct gfs2_journal_extent *jext;
2245 if (!list_empty(&jd->extent_list)) {
2246 jext = list_entry(jd->extent_list.prev, struct gfs2_journal_extent, list);
2247 if ((jext->dblock + jext->blocks) == dblock) {
2248 jext->blocks += blocks;
2253 jext = kzalloc(sizeof(struct gfs2_journal_extent), GFP_NOFS);
2256 jext->dblock = dblock;
2257 jext->lblock = lblock;
2258 jext->blocks = blocks;
2259 list_add_tail(&jext->list, &jd->extent_list);
2265 * gfs2_map_journal_extents - Cache journal bmap info
2266 * @sdp: The super block
2267 * @jd: The journal to map
2269 * Create a reusable "extent" mapping from all logical
2270 * blocks to all physical blocks for the given journal. This will save
2271 * us time when writing journal blocks. Most journals will have only one
2272 * extent that maps all their logical blocks. That's because gfs2.mkfs
2273 * arranges the journal blocks sequentially to maximize performance.
2274 * So the extent would map the first block for the entire file length.
2275 * However, gfs2_jadd can happen while file activity is happening, so
2276 * those journals may not be sequential. Less likely is the case where
2277 * the users created their own journals by mounting the metafs and
2278 * laying it out. But it's still possible. These journals might have
2281 * Returns: 0 on success, or error on failure
2284 int gfs2_map_journal_extents(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
2288 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
2289 struct buffer_head bh;
2290 unsigned int shift = sdp->sd_sb.sb_bsize_shift;
2295 start = ktime_get();
2296 lblock_stop = i_size_read(jd->jd_inode) >> shift;
2297 size = (lblock_stop - lblock) << shift;
2299 WARN_ON(!list_empty(&jd->extent_list));
2305 rc = gfs2_block_map(jd->jd_inode, lblock, &bh, 0);
2306 if (rc || !buffer_mapped(&bh))
2308 rc = gfs2_add_jextent(jd, lblock, bh.b_blocknr, bh.b_size >> shift);
2312 lblock += (bh.b_size >> ip->i_inode.i_blkbits);
2316 fs_info(sdp, "journal %d mapped with %u extents in %lldms\n", jd->jd_jid,
2317 jd->nr_extents, ktime_ms_delta(end, start));
2321 fs_warn(sdp, "error %d mapping journal %u at offset %llu (extent %u)\n",
2323 (unsigned long long)(i_size_read(jd->jd_inode) - size),
2325 fs_warn(sdp, "bmap=%d lblock=%llu block=%llu, state=0x%08lx, size=%llu\n",
2326 rc, (unsigned long long)lblock, (unsigned long long)bh.b_blocknr,
2327 bh.b_state, (unsigned long long)bh.b_size);
2328 gfs2_free_journal_extents(jd);
2333 * gfs2_write_alloc_required - figure out if a write will require an allocation
2334 * @ip: the file being written to
2335 * @offset: the offset to write to
2336 * @len: the number of bytes being written
2338 * Returns: 1 if an alloc is required, 0 otherwise
2341 int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
2344 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
2345 struct buffer_head bh;
2347 u64 lblock, lblock_stop, size;
2353 if (gfs2_is_stuffed(ip)) {
2354 if (offset + len > gfs2_max_stuffed_size(ip))
2359 shift = sdp->sd_sb.sb_bsize_shift;
2360 BUG_ON(gfs2_is_dir(ip));
2361 end_of_file = (i_size_read(&ip->i_inode) + sdp->sd_sb.sb_bsize - 1) >> shift;
2362 lblock = offset >> shift;
2363 lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift;
2364 if (lblock_stop > end_of_file && ip != GFS2_I(sdp->sd_rindex))
2367 size = (lblock_stop - lblock) << shift;
2371 gfs2_block_map(&ip->i_inode, lblock, &bh, 0);
2372 if (!buffer_mapped(&bh))
2375 lblock += (bh.b_size >> ip->i_inode.i_blkbits);
2381 static int stuffed_zero_range(struct inode *inode, loff_t offset, loff_t length)
2383 struct gfs2_inode *ip = GFS2_I(inode);
2384 struct buffer_head *dibh;
2387 if (offset >= inode->i_size)
2389 if (offset + length > inode->i_size)
2390 length = inode->i_size - offset;
2392 error = gfs2_meta_inode_buffer(ip, &dibh);
2395 gfs2_trans_add_meta(ip->i_gl, dibh);
2396 memset(dibh->b_data + sizeof(struct gfs2_dinode) + offset, 0,
2402 static int gfs2_journaled_truncate_range(struct inode *inode, loff_t offset,
2405 struct gfs2_sbd *sdp = GFS2_SB(inode);
2406 loff_t max_chunk = GFS2_JTRUNC_REVOKES * sdp->sd_vfs->s_blocksize;
2410 struct gfs2_trans *tr;
2415 if (chunk > max_chunk)
2418 offs = offset & ~PAGE_MASK;
2419 if (offs && chunk > PAGE_SIZE)
2420 chunk = offs + ((chunk - offs) & PAGE_MASK);
2422 truncate_pagecache_range(inode, offset, chunk);
2426 tr = current->journal_info;
2427 if (!test_bit(TR_TOUCHED, &tr->tr_flags))
2430 gfs2_trans_end(sdp);
2431 error = gfs2_trans_begin(sdp, RES_DINODE, GFS2_JTRUNC_REVOKES);
2438 int __gfs2_punch_hole(struct file *file, loff_t offset, loff_t length)
2440 struct inode *inode = file_inode(file);
2441 struct gfs2_inode *ip = GFS2_I(inode);
2442 struct gfs2_sbd *sdp = GFS2_SB(inode);
2445 if (gfs2_is_jdata(ip))
2446 error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_JDATA,
2447 GFS2_JTRUNC_REVOKES);
2449 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
2453 if (gfs2_is_stuffed(ip)) {
2454 error = stuffed_zero_range(inode, offset, length);
2458 unsigned int start_off, end_len, blocksize;
2460 blocksize = i_blocksize(inode);
2461 start_off = offset & (blocksize - 1);
2462 end_len = (offset + length) & (blocksize - 1);
2464 unsigned int len = length;
2465 if (length > blocksize - start_off)
2466 len = blocksize - start_off;
2467 error = gfs2_block_zero_range(inode, offset, len);
2470 if (start_off + length < blocksize)
2474 error = gfs2_block_zero_range(inode,
2475 offset + length - end_len, end_len);
2481 if (gfs2_is_jdata(ip)) {
2482 BUG_ON(!current->journal_info);
2483 gfs2_journaled_truncate_range(inode, offset, length);
2485 truncate_pagecache_range(inode, offset, offset + length - 1);
2487 file_update_time(file);
2488 mark_inode_dirty(inode);
2490 if (current->journal_info)
2491 gfs2_trans_end(sdp);
2493 if (!gfs2_is_stuffed(ip))
2494 error = punch_hole(ip, offset, length);
2497 if (current->journal_info)
2498 gfs2_trans_end(sdp);