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/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/gfs2_ondisk.h>
16 #include <linux/crc32.h>
17 #include <linux/lm_interface.h>
30 #include "ops_address.h"
32 /* This doesn't need to be that large as max 64 bit pointers in a 4k
33 * block is 512, so __u16 is fine for that. It saves stack space to
37 __u16 mp_list[GFS2_MAX_META_HEIGHT];
40 typedef int (*block_call_t) (struct gfs2_inode *ip, struct buffer_head *dibh,
41 struct buffer_head *bh, u64 *top,
42 u64 *bottom, unsigned int height,
47 unsigned int sm_height;
51 * gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page
53 * @dibh: the dinode buffer
54 * @block: the block number that was allocated
55 * @private: any locked page held by the caller process
60 static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh,
61 u64 block, struct page *page)
63 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
64 struct inode *inode = &ip->i_inode;
65 struct buffer_head *bh;
68 if (!page || page->index) {
69 page = grab_cache_page(inode->i_mapping, 0);
75 if (!PageUptodate(page)) {
76 void *kaddr = kmap(page);
78 memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode),
80 memset(kaddr + ip->i_di.di_size, 0,
81 PAGE_CACHE_SIZE - ip->i_di.di_size);
84 SetPageUptodate(page);
87 if (!page_has_buffers(page))
88 create_empty_buffers(page, 1 << inode->i_blkbits,
91 bh = page_buffers(page);
93 if (!buffer_mapped(bh))
94 map_bh(bh, inode->i_sb, block);
96 set_buffer_uptodate(bh);
97 if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
98 gfs2_trans_add_bh(ip->i_gl, bh, 0);
99 mark_buffer_dirty(bh);
103 page_cache_release(page);
110 * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big
111 * @ip: The GFS2 inode to unstuff
112 * @unstuffer: the routine that handles unstuffing a non-zero length file
113 * @private: private data for the unstuffer
115 * This routine unstuffs a dinode and returns it to a "normal" state such
116 * that the height can be grown in the traditional way.
121 int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page)
123 struct buffer_head *bh, *dibh;
125 int isdir = gfs2_is_dir(ip);
128 down_write(&ip->i_rw_mutex);
130 error = gfs2_meta_inode_buffer(ip, &dibh);
134 if (ip->i_di.di_size) {
135 /* Get a free block, fill it with the stuffed data,
136 and write it out to disk */
139 block = gfs2_alloc_meta(ip);
141 error = gfs2_dir_get_new_buffer(ip, block, &bh);
144 gfs2_buffer_copy_tail(bh,
145 sizeof(struct gfs2_meta_header),
146 dibh, sizeof(struct gfs2_dinode));
149 block = gfs2_alloc_data(ip);
151 error = gfs2_unstuffer_page(ip, dibh, block, page);
157 /* Set up the pointer to the new block */
159 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
161 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
163 if (ip->i_di.di_size) {
164 *(u64 *)(dibh->b_data + sizeof(struct gfs2_dinode)) =
166 ip->i_di.di_blocks++;
169 ip->i_di.di_height = 1;
171 gfs2_dinode_out(&ip->i_di, dibh->b_data);
176 up_write(&ip->i_rw_mutex);
181 * calc_tree_height - Calculate the height of a metadata tree
182 * @ip: The GFS2 inode
183 * @size: The proposed size of the file
185 * Work out how tall a metadata tree needs to be in order to accommodate a
186 * file of a particular size. If size is less than the current size of
187 * the inode, then the current size of the inode is used instead of the
190 * Returns: the height the tree should be
193 static unsigned int calc_tree_height(struct gfs2_inode *ip, u64 size)
195 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
197 unsigned int max, height;
199 if (ip->i_di.di_size > size)
200 size = ip->i_di.di_size;
202 if (gfs2_is_dir(ip)) {
203 arr = sdp->sd_jheightsize;
204 max = sdp->sd_max_jheight;
206 arr = sdp->sd_heightsize;
207 max = sdp->sd_max_height;
210 for (height = 0; height < max; height++)
211 if (arr[height] >= size)
218 * build_height - Build a metadata tree of the requested height
219 * @ip: The GFS2 inode
220 * @height: The height to build to
226 static int build_height(struct inode *inode, unsigned height)
228 struct gfs2_inode *ip = GFS2_I(inode);
229 unsigned new_height = height - ip->i_di.di_height;
230 struct buffer_head *dibh;
231 struct buffer_head *blocks[GFS2_MAX_META_HEIGHT];
237 if (height <= ip->i_di.di_height)
240 error = gfs2_meta_inode_buffer(ip, &dibh);
244 for(n = 0; n < new_height; n++) {
245 bn = gfs2_alloc_meta(ip);
246 blocks[n] = gfs2_meta_new(ip->i_gl, bn);
247 gfs2_trans_add_bh(ip->i_gl, blocks[n], 1);
251 bn = blocks[0]->b_blocknr;
252 if (new_height > 1) {
253 for(; n < new_height-1; n++) {
254 gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN,
256 gfs2_buffer_clear_tail(blocks[n],
257 sizeof(struct gfs2_meta_header));
258 bp = (u64 *)(blocks[n]->b_data +
259 sizeof(struct gfs2_meta_header));
260 *bp = cpu_to_be64(blocks[n+1]->b_blocknr);
265 gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN, GFS2_FORMAT_IN);
266 gfs2_buffer_copy_tail(blocks[n], sizeof(struct gfs2_meta_header),
267 dibh, sizeof(struct gfs2_dinode));
269 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
270 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
271 bp = (u64 *)(dibh->b_data + sizeof(struct gfs2_dinode));
272 *bp = cpu_to_be64(bn);
273 ip->i_di.di_height += new_height;
274 ip->i_di.di_blocks += new_height;
275 gfs2_dinode_out(&ip->i_di, dibh->b_data);
281 * find_metapath - Find path through the metadata tree
282 * @ip: The inode pointer
283 * @mp: The metapath to return the result in
284 * @block: The disk block to look up
286 * This routine returns a struct metapath structure that defines a path
287 * through the metadata of inode "ip" to get to block "block".
290 * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
291 * filesystem with a blocksize of 4096.
293 * find_metapath() would return a struct metapath structure set to:
294 * mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48,
295 * and mp_list[2] = 165.
297 * That means that in order to get to the block containing the byte at
298 * offset 101342453, we would load the indirect block pointed to by pointer
299 * 0 in the dinode. We would then load the indirect block pointed to by
300 * pointer 48 in that indirect block. We would then load the data block
301 * pointed to by pointer 165 in that indirect block.
303 * ----------------------------------------
308 * ----------------------------------------
312 * ----------------------------------------
316 * |0 5 6 7 8 9 0 1 2|
317 * ----------------------------------------
321 * ----------------------------------------
326 * ----------------------------------------
330 * ----------------------------------------
331 * | Data block containing offset |
335 * ----------------------------------------
339 static void find_metapath(struct gfs2_inode *ip, u64 block,
342 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
346 for (i = ip->i_di.di_height; i--;)
347 mp->mp_list[i] = do_div(b, sdp->sd_inptrs);
352 * metapointer - Return pointer to start of metadata in a buffer
354 * @height: The metadata height (0 = dinode)
357 * Return a pointer to the block number of the next height of the metadata
358 * tree given a buffer containing the pointer to the current height of the
362 static inline u64 *metapointer(struct buffer_head *bh, int *boundary,
363 unsigned int height, const struct metapath *mp)
365 unsigned int head_size = (height > 0) ?
366 sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode);
369 ptr = ((u64 *)(bh->b_data + head_size)) + mp->mp_list[height];
370 if (ptr + 1 == (u64 *)(bh->b_data + bh->b_size))
376 * lookup_block - Get the next metadata block in metadata tree
377 * @ip: The GFS2 inode
378 * @bh: Buffer containing the pointers to metadata blocks
379 * @height: The height of the tree (0 = dinode)
381 * @create: Non-zero if we may create a new meatdata block
382 * @new: Used to indicate if we did create a new metadata block
383 * @block: the returned disk block number
385 * Given a metatree, complete to a particular height, checks to see if the next
386 * height of the tree exists. If not the next height of the tree is created.
387 * The block number of the next height of the metadata tree is returned.
391 static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh,
392 unsigned int height, struct metapath *mp, int create,
393 int *new, u64 *block)
396 u64 *ptr = metapointer(bh, &boundary, height, mp);
399 *block = be64_to_cpu(*ptr);
408 if (height == ip->i_di.di_height - 1 && !gfs2_is_dir(ip))
409 *block = gfs2_alloc_data(ip);
411 *block = gfs2_alloc_meta(ip);
413 gfs2_trans_add_bh(ip->i_gl, bh, 1);
415 *ptr = cpu_to_be64(*block);
416 ip->i_di.di_blocks++;
423 * gfs2_block_pointers - Map a block from an inode to a disk block
425 * @lblock: The logical block number
426 * @map_bh: The bh to be mapped
427 * @mp: metapath to use
429 * Find the block number on the current device which corresponds to an
430 * inode's block. If the block had to be created, "new" will be set.
435 static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create,
436 struct buffer_head *bh_map, struct metapath *mp,
439 struct gfs2_inode *ip = GFS2_I(inode);
440 struct gfs2_sbd *sdp = GFS2_SB(inode);
441 struct buffer_head *bh;
444 unsigned int end_of_metadata;
451 if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip)))
454 bsize = gfs2_is_dir(ip) ? sdp->sd_jbsize : sdp->sd_sb.sb_bsize;
456 height = calc_tree_height(ip, (lblock + 1) * bsize);
457 if (ip->i_di.di_height < height) {
461 error = build_height(inode, height);
466 find_metapath(ip, lblock, mp);
467 end_of_metadata = ip->i_di.di_height - 1;
469 error = gfs2_meta_inode_buffer(ip, &bh);
473 for (x = 0; x < end_of_metadata; x++) {
474 lookup_block(ip, bh, x, mp, create, &new, &dblock);
479 error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh);
484 boundary = lookup_block(ip, bh, end_of_metadata, mp, create, &new, &dblock);
485 clear_buffer_mapped(bh_map);
486 clear_buffer_new(bh_map);
487 clear_buffer_boundary(bh_map);
490 map_bh(bh_map, inode->i_sb, dblock);
492 set_buffer_boundary(bh);
494 struct buffer_head *dibh;
495 error = gfs2_meta_inode_buffer(ip, &dibh);
497 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
498 gfs2_dinode_out(&ip->i_di, dibh->b_data);
501 set_buffer_new(bh_map);
504 while(--maxlen && !buffer_boundary(bh_map)) {
507 mp->mp_list[end_of_metadata]++;
508 boundary = lookup_block(ip, bh, end_of_metadata, mp, 0, &new, &eblock);
509 if (eblock != ++dblock)
511 bh_map->b_size += (1 << inode->i_blkbits);
513 set_buffer_boundary(bh_map);
522 static inline void bmap_lock(struct inode *inode, int create)
524 struct gfs2_inode *ip = GFS2_I(inode);
526 down_write(&ip->i_rw_mutex);
528 down_read(&ip->i_rw_mutex);
531 static inline void bmap_unlock(struct inode *inode, int create)
533 struct gfs2_inode *ip = GFS2_I(inode);
535 up_write(&ip->i_rw_mutex);
537 up_read(&ip->i_rw_mutex);
540 int gfs2_block_map(struct inode *inode, u64 lblock, int create,
541 struct buffer_head *bh, unsigned int maxlen)
546 bmap_lock(inode, create);
547 ret = gfs2_block_pointers(inode, lblock, create, bh, &mp, maxlen);
548 bmap_unlock(inode, create);
552 int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
555 struct buffer_head bh = { .b_state = 0, .b_blocknr = 0, .b_size = 0 };
563 bmap_lock(inode, create);
564 ret = gfs2_block_pointers(inode, lblock, create, &bh, &mp, *extlen);
565 bmap_unlock(inode, create);
566 *extlen = bh.b_size >> inode->i_blkbits;
567 *dblock = bh.b_blocknr;
576 * recursive_scan - recursively scan through the end of a file
578 * @dibh: the dinode buffer
579 * @mp: the path through the metadata to the point to start
580 * @height: the height the recursion is at
581 * @block: the indirect block to look at
582 * @first: 1 if this is the first block
583 * @bc: the call to make for each piece of metadata
584 * @data: data opaque to this function to pass to @bc
586 * When this is first called @height and @block should be zero and
587 * @first should be 1.
592 static int recursive_scan(struct gfs2_inode *ip, struct buffer_head *dibh,
593 struct metapath *mp, unsigned int height,
594 u64 block, int first, block_call_t bc,
597 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
598 struct buffer_head *bh = NULL;
602 int mh_size = sizeof(struct gfs2_meta_header);
605 error = gfs2_meta_inode_buffer(ip, &bh);
610 top = (u64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + mp->mp_list[0];
611 bottom = (u64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + sdp->sd_diptrs;
613 error = gfs2_meta_indirect_buffer(ip, height, block, 0, &bh);
617 top = (u64 *)(bh->b_data + mh_size) +
618 (first ? mp->mp_list[height] : 0);
620 bottom = (u64 *)(bh->b_data + mh_size) + sdp->sd_inptrs;
623 error = bc(ip, dibh, bh, top, bottom, height, data);
627 if (height < ip->i_di.di_height - 1)
628 for (; top < bottom; top++, first = 0) {
632 bn = be64_to_cpu(*top);
634 error = recursive_scan(ip, dibh, mp, height + 1, bn,
646 * do_strip - Look for a layer a particular layer of the file and strip it off
648 * @dibh: the dinode buffer
649 * @bh: A buffer of pointers
650 * @top: The first pointer in the buffer
651 * @bottom: One more than the last pointer
652 * @height: the height this buffer is at
653 * @data: a pointer to a struct strip_mine
658 static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh,
659 struct buffer_head *bh, u64 *top, u64 *bottom,
660 unsigned int height, void *data)
662 struct strip_mine *sm = data;
663 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
664 struct gfs2_rgrp_list rlist;
668 unsigned int rg_blocks = 0;
670 unsigned int revokes = 0;
677 if (height != sm->sm_height)
685 metadata = (height != ip->i_di.di_height - 1);
687 revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs;
689 error = gfs2_rindex_hold(sdp, &ip->i_alloc.al_ri_gh);
693 memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
697 for (p = top; p < bottom; p++) {
701 bn = be64_to_cpu(*p);
703 if (bstart + blen == bn)
707 gfs2_rlist_add(sdp, &rlist, bstart);
715 gfs2_rlist_add(sdp, &rlist, bstart);
717 goto out; /* Nothing to do */
719 gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE, 0);
721 for (x = 0; x < rlist.rl_rgrps; x++) {
722 struct gfs2_rgrpd *rgd;
723 rgd = rlist.rl_ghs[x].gh_gl->gl_object;
724 rg_blocks += rgd->rd_ri.ri_length;
727 error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
731 error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE +
732 RES_INDIRECT + RES_STATFS + RES_QUOTA,
737 down_write(&ip->i_rw_mutex);
739 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
740 gfs2_trans_add_bh(ip->i_gl, bh, 1);
745 for (p = top; p < bottom; p++) {
749 bn = be64_to_cpu(*p);
751 if (bstart + blen == bn)
756 gfs2_free_meta(ip, bstart, blen);
758 gfs2_free_data(ip, bstart, blen);
766 if (!ip->i_di.di_blocks)
767 gfs2_consist_inode(ip);
768 ip->i_di.di_blocks--;
772 gfs2_free_meta(ip, bstart, blen);
774 gfs2_free_data(ip, bstart, blen);
777 ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
779 gfs2_dinode_out(&ip->i_di, dibh->b_data);
781 up_write(&ip->i_rw_mutex);
786 gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
788 gfs2_rlist_free(&rlist);
790 gfs2_glock_dq_uninit(&ip->i_alloc.al_ri_gh);
795 * do_grow - Make a file look bigger than it is
797 * @size: the size to set the file to
799 * Called with an exclusive lock on @ip.
804 static int do_grow(struct gfs2_inode *ip, u64 size)
806 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
807 struct gfs2_alloc *al;
808 struct buffer_head *dibh;
812 al = gfs2_alloc_get(ip);
814 error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
818 error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
822 al->al_requested = sdp->sd_max_height + RES_DATA;
824 error = gfs2_inplace_reserve(ip);
828 error = gfs2_trans_begin(sdp,
829 sdp->sd_max_height + al->al_rgd->rd_ri.ri_length +
830 RES_JDATA + RES_DINODE + RES_STATFS + RES_QUOTA, 0);
834 if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
835 if (gfs2_is_stuffed(ip)) {
836 error = gfs2_unstuff_dinode(ip, NULL);
841 h = calc_tree_height(ip, size);
842 if (ip->i_di.di_height < h) {
843 down_write(&ip->i_rw_mutex);
844 error = build_height(&ip->i_inode, h);
845 up_write(&ip->i_rw_mutex);
851 ip->i_di.di_size = size;
852 ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
854 error = gfs2_meta_inode_buffer(ip, &dibh);
858 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
859 gfs2_dinode_out(&ip->i_di, dibh->b_data);
865 gfs2_inplace_release(ip);
867 gfs2_quota_unlock(ip);
875 * gfs2_block_truncate_page - Deal with zeroing out data for truncate
877 * This is partly borrowed from ext3.
879 static int gfs2_block_truncate_page(struct address_space *mapping)
881 struct inode *inode = mapping->host;
882 struct gfs2_inode *ip = GFS2_I(inode);
883 struct gfs2_sbd *sdp = GFS2_SB(inode);
884 loff_t from = inode->i_size;
885 unsigned long index = from >> PAGE_CACHE_SHIFT;
886 unsigned offset = from & (PAGE_CACHE_SIZE-1);
887 unsigned blocksize, iblock, length, pos;
888 struct buffer_head *bh;
893 page = grab_cache_page(mapping, index);
897 blocksize = inode->i_sb->s_blocksize;
898 length = blocksize - (offset & (blocksize - 1));
899 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
901 if (!page_has_buffers(page))
902 create_empty_buffers(page, blocksize, 0);
904 /* Find the buffer that contains "offset" */
905 bh = page_buffers(page);
907 while (offset >= pos) {
908 bh = bh->b_this_page;
915 if (!buffer_mapped(bh)) {
916 gfs2_get_block(inode, iblock, bh, 0);
917 /* unmapped? It's a hole - nothing to do */
918 if (!buffer_mapped(bh))
922 /* Ok, it's mapped. Make sure it's up-to-date */
923 if (PageUptodate(page))
924 set_buffer_uptodate(bh);
926 if (!buffer_uptodate(bh)) {
928 ll_rw_block(READ, 1, &bh);
930 /* Uhhuh. Read error. Complain and punt. */
931 if (!buffer_uptodate(bh))
935 if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
936 gfs2_trans_add_bh(ip->i_gl, bh, 0);
938 kaddr = kmap_atomic(page, KM_USER0);
939 memset(kaddr + offset, 0, length);
940 flush_dcache_page(page);
941 kunmap_atomic(kaddr, KM_USER0);
945 page_cache_release(page);
949 static int trunc_start(struct gfs2_inode *ip, u64 size)
951 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
952 struct buffer_head *dibh;
953 int journaled = gfs2_is_jdata(ip);
956 error = gfs2_trans_begin(sdp,
957 RES_DINODE + (journaled ? RES_JDATA : 0), 0);
961 error = gfs2_meta_inode_buffer(ip, &dibh);
965 if (gfs2_is_stuffed(ip)) {
966 ip->i_di.di_size = size;
967 ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
968 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
969 gfs2_dinode_out(&ip->i_di, dibh->b_data);
970 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + size);
974 if (size & (u64)(sdp->sd_sb.sb_bsize - 1))
975 error = gfs2_block_truncate_page(ip->i_inode.i_mapping);
978 ip->i_di.di_size = size;
979 ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
980 ip->i_di.di_flags |= GFS2_DIF_TRUNC_IN_PROG;
981 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
982 gfs2_dinode_out(&ip->i_di, dibh->b_data);
993 static int trunc_dealloc(struct gfs2_inode *ip, u64 size)
995 unsigned int height = ip->i_di.di_height;
1003 lblock = (size - 1) >> GFS2_SB(&ip->i_inode)->sd_sb.sb_bsize_shift;
1005 find_metapath(ip, lblock, &mp);
1008 error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1013 struct strip_mine sm;
1014 sm.sm_first = !!size;
1015 sm.sm_height = height;
1017 error = recursive_scan(ip, NULL, &mp, 0, 0, 1, do_strip, &sm);
1022 gfs2_quota_unhold(ip);
1029 static int trunc_end(struct gfs2_inode *ip)
1031 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1032 struct buffer_head *dibh;
1035 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1039 down_write(&ip->i_rw_mutex);
1041 error = gfs2_meta_inode_buffer(ip, &dibh);
1045 if (!ip->i_di.di_size) {
1046 ip->i_di.di_height = 0;
1047 ip->i_di.di_goal_meta =
1048 ip->i_di.di_goal_data =
1050 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
1052 ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
1053 ip->i_di.di_flags &= ~GFS2_DIF_TRUNC_IN_PROG;
1055 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1056 gfs2_dinode_out(&ip->i_di, dibh->b_data);
1060 up_write(&ip->i_rw_mutex);
1061 gfs2_trans_end(sdp);
1066 * do_shrink - make a file smaller
1068 * @size: the size to make the file
1069 * @truncator: function to truncate the last partial block
1071 * Called with an exclusive lock on @ip.
1076 static int do_shrink(struct gfs2_inode *ip, u64 size)
1080 error = trunc_start(ip, size);
1086 error = trunc_dealloc(ip, size);
1088 error = trunc_end(ip);
1094 * gfs2_truncatei - make a file a given size
1096 * @size: the size to make the file
1097 * @truncator: function to truncate the last partial block
1099 * The file size can grow, shrink, or stay the same size.
1104 int gfs2_truncatei(struct gfs2_inode *ip, u64 size)
1108 if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), S_ISREG(ip->i_di.di_mode)))
1111 if (size > ip->i_di.di_size)
1112 error = do_grow(ip, size);
1114 error = do_shrink(ip, size);
1119 int gfs2_truncatei_resume(struct gfs2_inode *ip)
1122 error = trunc_dealloc(ip, ip->i_di.di_size);
1124 error = trunc_end(ip);
1128 int gfs2_file_dealloc(struct gfs2_inode *ip)
1130 return trunc_dealloc(ip, 0);
1134 * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file
1136 * @len: the number of bytes to be written to the file
1137 * @data_blocks: returns the number of data blocks required
1138 * @ind_blocks: returns the number of indirect blocks required
1142 void gfs2_write_calc_reserv(struct gfs2_inode *ip, unsigned int len,
1143 unsigned int *data_blocks, unsigned int *ind_blocks)
1145 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1148 if (gfs2_is_dir(ip)) {
1149 *data_blocks = DIV_ROUND_UP(len, sdp->sd_jbsize) + 2;
1150 *ind_blocks = 3 * (sdp->sd_max_jheight - 1);
1152 *data_blocks = (len >> sdp->sd_sb.sb_bsize_shift) + 3;
1153 *ind_blocks = 3 * (sdp->sd_max_height - 1);
1156 for (tmp = *data_blocks; tmp > sdp->sd_diptrs;) {
1157 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
1163 * gfs2_write_alloc_required - figure out if a write will require an allocation
1164 * @ip: the file being written to
1165 * @offset: the offset to write to
1166 * @len: the number of bytes being written
1167 * @alloc_required: set to 1 if an alloc is required, 0 otherwise
1172 int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
1173 unsigned int len, int *alloc_required)
1175 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1176 u64 lblock, lblock_stop, dblock;
1181 *alloc_required = 0;
1186 if (gfs2_is_stuffed(ip)) {
1188 sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode))
1189 *alloc_required = 1;
1193 if (gfs2_is_dir(ip)) {
1194 unsigned int bsize = sdp->sd_jbsize;
1196 do_div(lblock, bsize);
1197 lblock_stop = offset + len + bsize - 1;
1198 do_div(lblock_stop, bsize);
1200 unsigned int shift = sdp->sd_sb.sb_bsize_shift;
1201 lblock = offset >> shift;
1202 lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift;
1205 for (; lblock < lblock_stop; lblock += extlen) {
1206 error = gfs2_extent_map(&ip->i_inode, lblock, &new, &dblock, &extlen);
1211 *alloc_required = 1;