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, __be64 *top,
42 __be64 *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;
124 struct gfs2_dinode *di;
126 int isdir = gfs2_is_dir(ip);
129 down_write(&ip->i_rw_mutex);
131 error = gfs2_meta_inode_buffer(ip, &dibh);
135 if (ip->i_di.di_size) {
136 /* Get a free block, fill it with the stuffed data,
137 and write it out to disk */
140 block = gfs2_alloc_meta(ip);
142 error = gfs2_dir_get_new_buffer(ip, block, &bh);
145 gfs2_buffer_copy_tail(bh, 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);
160 di = (struct gfs2_dinode *)dibh->b_data;
161 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
163 if (ip->i_di.di_size) {
164 *(__be64 *)(di + 1) = cpu_to_be64(block);
165 ip->i_di.di_blocks++;
166 gfs2_set_inode_blocks(&ip->i_inode);
167 di->di_blocks = cpu_to_be64(ip->i_di.di_blocks);
170 ip->i_di.di_height = 1;
171 di->di_height = cpu_to_be16(1);
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];
232 struct gfs2_dinode *di;
238 if (height <= ip->i_di.di_height)
241 error = gfs2_meta_inode_buffer(ip, &dibh);
245 for(n = 0; n < new_height; n++) {
246 bn = gfs2_alloc_meta(ip);
247 blocks[n] = gfs2_meta_new(ip->i_gl, bn);
248 gfs2_trans_add_bh(ip->i_gl, blocks[n], 1);
252 bn = blocks[0]->b_blocknr;
253 if (new_height > 1) {
254 for(; n < new_height-1; n++) {
255 gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN,
257 gfs2_buffer_clear_tail(blocks[n],
258 sizeof(struct gfs2_meta_header));
259 bp = (__be64 *)(blocks[n]->b_data +
260 sizeof(struct gfs2_meta_header));
261 *bp = cpu_to_be64(blocks[n+1]->b_blocknr);
266 gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN, GFS2_FORMAT_IN);
267 gfs2_buffer_copy_tail(blocks[n], sizeof(struct gfs2_meta_header),
268 dibh, sizeof(struct gfs2_dinode));
270 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
271 di = (struct gfs2_dinode *)dibh->b_data;
272 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
273 *(__be64 *)(di + 1) = cpu_to_be64(bn);
274 ip->i_di.di_height += new_height;
275 ip->i_di.di_blocks += new_height;
276 gfs2_set_inode_blocks(&ip->i_inode);
277 di->di_height = cpu_to_be16(ip->i_di.di_height);
278 di->di_blocks = cpu_to_be64(ip->i_di.di_blocks);
284 * find_metapath - Find path through the metadata tree
285 * @ip: The inode pointer
286 * @mp: The metapath to return the result in
287 * @block: The disk block to look up
289 * This routine returns a struct metapath structure that defines a path
290 * through the metadata of inode "ip" to get to block "block".
293 * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
294 * filesystem with a blocksize of 4096.
296 * find_metapath() would return a struct metapath structure set to:
297 * mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48,
298 * and mp_list[2] = 165.
300 * That means that in order to get to the block containing the byte at
301 * offset 101342453, we would load the indirect block pointed to by pointer
302 * 0 in the dinode. We would then load the indirect block pointed to by
303 * pointer 48 in that indirect block. We would then load the data block
304 * pointed to by pointer 165 in that indirect block.
306 * ----------------------------------------
311 * ----------------------------------------
315 * ----------------------------------------
319 * |0 5 6 7 8 9 0 1 2|
320 * ----------------------------------------
324 * ----------------------------------------
329 * ----------------------------------------
333 * ----------------------------------------
334 * | Data block containing offset |
338 * ----------------------------------------
342 static void find_metapath(struct gfs2_inode *ip, u64 block,
345 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
349 for (i = ip->i_di.di_height; i--;)
350 mp->mp_list[i] = do_div(b, sdp->sd_inptrs);
355 * metapointer - Return pointer to start of metadata in a buffer
357 * @height: The metadata height (0 = dinode)
360 * Return a pointer to the block number of the next height of the metadata
361 * tree given a buffer containing the pointer to the current height of the
365 static inline __be64 *metapointer(struct buffer_head *bh, int *boundary,
366 unsigned int height, const struct metapath *mp)
368 unsigned int head_size = (height > 0) ?
369 sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode);
372 ptr = ((__be64 *)(bh->b_data + head_size)) + mp->mp_list[height];
373 if (ptr + 1 == (__be64 *)(bh->b_data + bh->b_size))
379 * lookup_block - Get the next metadata block in metadata tree
380 * @ip: The GFS2 inode
381 * @bh: Buffer containing the pointers to metadata blocks
382 * @height: The height of the tree (0 = dinode)
384 * @create: Non-zero if we may create a new meatdata block
385 * @new: Used to indicate if we did create a new metadata block
386 * @block: the returned disk block number
388 * Given a metatree, complete to a particular height, checks to see if the next
389 * height of the tree exists. If not the next height of the tree is created.
390 * The block number of the next height of the metadata tree is returned.
394 static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh,
395 unsigned int height, struct metapath *mp, int create,
396 int *new, u64 *block)
399 __be64 *ptr = metapointer(bh, &boundary, height, mp);
402 *block = be64_to_cpu(*ptr);
411 if (height == ip->i_di.di_height - 1 && !gfs2_is_dir(ip))
412 *block = gfs2_alloc_data(ip);
414 *block = gfs2_alloc_meta(ip);
416 gfs2_trans_add_bh(ip->i_gl, bh, 1);
418 *ptr = cpu_to_be64(*block);
419 ip->i_di.di_blocks++;
420 gfs2_set_inode_blocks(&ip->i_inode);
427 * gfs2_block_pointers - Map a block from an inode to a disk block
429 * @lblock: The logical block number
430 * @map_bh: The bh to be mapped
431 * @mp: metapath to use
433 * Find the block number on the current device which corresponds to an
434 * inode's block. If the block had to be created, "new" will be set.
439 static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create,
440 struct buffer_head *bh_map, struct metapath *mp)
442 struct gfs2_inode *ip = GFS2_I(inode);
443 struct gfs2_sbd *sdp = GFS2_SB(inode);
444 struct buffer_head *bh;
447 unsigned int end_of_metadata;
453 unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
457 if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip)))
460 bsize = gfs2_is_dir(ip) ? sdp->sd_jbsize : sdp->sd_sb.sb_bsize;
462 height = calc_tree_height(ip, (lblock + 1) * bsize);
463 if (ip->i_di.di_height < height) {
467 error = build_height(inode, height);
472 find_metapath(ip, lblock, mp);
473 end_of_metadata = ip->i_di.di_height - 1;
475 error = gfs2_meta_inode_buffer(ip, &bh);
479 for (x = 0; x < end_of_metadata; x++) {
480 lookup_block(ip, bh, x, mp, create, &new, &dblock);
485 error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh);
490 boundary = lookup_block(ip, bh, end_of_metadata, mp, create, &new, &dblock);
491 clear_buffer_mapped(bh_map);
492 clear_buffer_new(bh_map);
493 clear_buffer_boundary(bh_map);
496 map_bh(bh_map, inode->i_sb, dblock);
498 set_buffer_boundary(bh);
500 struct buffer_head *dibh;
501 error = gfs2_meta_inode_buffer(ip, &dibh);
503 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
504 gfs2_dinode_out(ip, dibh->b_data);
507 set_buffer_new(bh_map);
510 while(--maxlen && !buffer_boundary(bh_map)) {
513 mp->mp_list[end_of_metadata]++;
514 boundary = lookup_block(ip, bh, end_of_metadata, mp, 0, &new, &eblock);
515 if (eblock != ++dblock)
517 bh_map->b_size += (1 << inode->i_blkbits);
519 set_buffer_boundary(bh_map);
528 static inline void bmap_lock(struct inode *inode, int create)
530 struct gfs2_inode *ip = GFS2_I(inode);
532 down_write(&ip->i_rw_mutex);
534 down_read(&ip->i_rw_mutex);
537 static inline void bmap_unlock(struct inode *inode, int create)
539 struct gfs2_inode *ip = GFS2_I(inode);
541 up_write(&ip->i_rw_mutex);
543 up_read(&ip->i_rw_mutex);
546 int gfs2_block_map(struct inode *inode, u64 lblock, int create,
547 struct buffer_head *bh)
552 bmap_lock(inode, create);
553 ret = gfs2_block_pointers(inode, lblock, create, bh, &mp);
554 bmap_unlock(inode, create);
558 int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
561 struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 };
569 bh.b_size = 1 << (inode->i_blkbits + 5);
570 bmap_lock(inode, create);
571 ret = gfs2_block_pointers(inode, lblock, create, &bh, &mp);
572 bmap_unlock(inode, create);
573 *extlen = bh.b_size >> inode->i_blkbits;
574 *dblock = bh.b_blocknr;
583 * recursive_scan - recursively scan through the end of a file
585 * @dibh: the dinode buffer
586 * @mp: the path through the metadata to the point to start
587 * @height: the height the recursion is at
588 * @block: the indirect block to look at
589 * @first: 1 if this is the first block
590 * @bc: the call to make for each piece of metadata
591 * @data: data opaque to this function to pass to @bc
593 * When this is first called @height and @block should be zero and
594 * @first should be 1.
599 static int recursive_scan(struct gfs2_inode *ip, struct buffer_head *dibh,
600 struct metapath *mp, unsigned int height,
601 u64 block, int first, block_call_t bc,
604 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
605 struct buffer_head *bh = NULL;
606 __be64 *top, *bottom;
609 int mh_size = sizeof(struct gfs2_meta_header);
612 error = gfs2_meta_inode_buffer(ip, &bh);
617 top = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + mp->mp_list[0];
618 bottom = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + sdp->sd_diptrs;
620 error = gfs2_meta_indirect_buffer(ip, height, block, 0, &bh);
624 top = (__be64 *)(bh->b_data + mh_size) +
625 (first ? mp->mp_list[height] : 0);
627 bottom = (__be64 *)(bh->b_data + mh_size) + sdp->sd_inptrs;
630 error = bc(ip, dibh, bh, top, bottom, height, data);
634 if (height < ip->i_di.di_height - 1)
635 for (; top < bottom; top++, first = 0) {
639 bn = be64_to_cpu(*top);
641 error = recursive_scan(ip, dibh, mp, height + 1, bn,
653 * do_strip - Look for a layer a particular layer of the file and strip it off
655 * @dibh: the dinode buffer
656 * @bh: A buffer of pointers
657 * @top: The first pointer in the buffer
658 * @bottom: One more than the last pointer
659 * @height: the height this buffer is at
660 * @data: a pointer to a struct strip_mine
665 static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh,
666 struct buffer_head *bh, __be64 *top, __be64 *bottom,
667 unsigned int height, void *data)
669 struct strip_mine *sm = data;
670 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
671 struct gfs2_rgrp_list rlist;
675 unsigned int rg_blocks = 0;
677 unsigned int revokes = 0;
684 if (height != sm->sm_height)
692 metadata = (height != ip->i_di.di_height - 1);
694 revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs;
696 error = gfs2_rindex_hold(sdp, &ip->i_alloc.al_ri_gh);
700 memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
704 for (p = top; p < bottom; p++) {
708 bn = be64_to_cpu(*p);
710 if (bstart + blen == bn)
714 gfs2_rlist_add(sdp, &rlist, bstart);
722 gfs2_rlist_add(sdp, &rlist, bstart);
724 goto out; /* Nothing to do */
726 gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE, 0);
728 for (x = 0; x < rlist.rl_rgrps; x++) {
729 struct gfs2_rgrpd *rgd;
730 rgd = rlist.rl_ghs[x].gh_gl->gl_object;
731 rg_blocks += rgd->rd_ri.ri_length;
734 error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
738 error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE +
739 RES_INDIRECT + RES_STATFS + RES_QUOTA,
744 down_write(&ip->i_rw_mutex);
746 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
747 gfs2_trans_add_bh(ip->i_gl, bh, 1);
752 for (p = top; p < bottom; p++) {
756 bn = be64_to_cpu(*p);
758 if (bstart + blen == bn)
763 gfs2_free_meta(ip, bstart, blen);
765 gfs2_free_data(ip, bstart, blen);
773 if (!ip->i_di.di_blocks)
774 gfs2_consist_inode(ip);
775 ip->i_di.di_blocks--;
776 gfs2_set_inode_blocks(&ip->i_inode);
780 gfs2_free_meta(ip, bstart, blen);
782 gfs2_free_data(ip, bstart, blen);
785 ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds();
787 gfs2_dinode_out(ip, dibh->b_data);
789 up_write(&ip->i_rw_mutex);
794 gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
796 gfs2_rlist_free(&rlist);
798 gfs2_glock_dq_uninit(&ip->i_alloc.al_ri_gh);
803 * do_grow - Make a file look bigger than it is
805 * @size: the size to set the file to
807 * Called with an exclusive lock on @ip.
812 static int do_grow(struct gfs2_inode *ip, u64 size)
814 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
815 struct gfs2_alloc *al;
816 struct buffer_head *dibh;
820 al = gfs2_alloc_get(ip);
822 error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
826 error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
830 al->al_requested = sdp->sd_max_height + RES_DATA;
832 error = gfs2_inplace_reserve(ip);
836 error = gfs2_trans_begin(sdp,
837 sdp->sd_max_height + al->al_rgd->rd_ri.ri_length +
838 RES_JDATA + RES_DINODE + RES_STATFS + RES_QUOTA, 0);
842 if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
843 if (gfs2_is_stuffed(ip)) {
844 error = gfs2_unstuff_dinode(ip, NULL);
849 h = calc_tree_height(ip, size);
850 if (ip->i_di.di_height < h) {
851 down_write(&ip->i_rw_mutex);
852 error = build_height(&ip->i_inode, h);
853 up_write(&ip->i_rw_mutex);
859 ip->i_di.di_size = size;
860 ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds();
862 error = gfs2_meta_inode_buffer(ip, &dibh);
866 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
867 gfs2_dinode_out(ip, dibh->b_data);
873 gfs2_inplace_release(ip);
875 gfs2_quota_unlock(ip);
883 * gfs2_block_truncate_page - Deal with zeroing out data for truncate
885 * This is partly borrowed from ext3.
887 static int gfs2_block_truncate_page(struct address_space *mapping)
889 struct inode *inode = mapping->host;
890 struct gfs2_inode *ip = GFS2_I(inode);
891 struct gfs2_sbd *sdp = GFS2_SB(inode);
892 loff_t from = inode->i_size;
893 unsigned long index = from >> PAGE_CACHE_SHIFT;
894 unsigned offset = from & (PAGE_CACHE_SIZE-1);
895 unsigned blocksize, iblock, length, pos;
896 struct buffer_head *bh;
901 page = grab_cache_page(mapping, index);
905 blocksize = inode->i_sb->s_blocksize;
906 length = blocksize - (offset & (blocksize - 1));
907 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
909 if (!page_has_buffers(page))
910 create_empty_buffers(page, blocksize, 0);
912 /* Find the buffer that contains "offset" */
913 bh = page_buffers(page);
915 while (offset >= pos) {
916 bh = bh->b_this_page;
923 if (!buffer_mapped(bh)) {
924 gfs2_get_block(inode, iblock, bh, 0);
925 /* unmapped? It's a hole - nothing to do */
926 if (!buffer_mapped(bh))
930 /* Ok, it's mapped. Make sure it's up-to-date */
931 if (PageUptodate(page))
932 set_buffer_uptodate(bh);
934 if (!buffer_uptodate(bh)) {
936 ll_rw_block(READ, 1, &bh);
938 /* Uhhuh. Read error. Complain and punt. */
939 if (!buffer_uptodate(bh))
943 if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
944 gfs2_trans_add_bh(ip->i_gl, bh, 0);
946 kaddr = kmap_atomic(page, KM_USER0);
947 memset(kaddr + offset, 0, length);
948 flush_dcache_page(page);
949 kunmap_atomic(kaddr, KM_USER0);
953 page_cache_release(page);
957 static int trunc_start(struct gfs2_inode *ip, u64 size)
959 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
960 struct buffer_head *dibh;
961 int journaled = gfs2_is_jdata(ip);
964 error = gfs2_trans_begin(sdp,
965 RES_DINODE + (journaled ? RES_JDATA : 0), 0);
969 error = gfs2_meta_inode_buffer(ip, &dibh);
973 if (gfs2_is_stuffed(ip)) {
974 ip->i_di.di_size = size;
975 ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds();
976 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
977 gfs2_dinode_out(ip, dibh->b_data);
978 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + size);
982 if (size & (u64)(sdp->sd_sb.sb_bsize - 1))
983 error = gfs2_block_truncate_page(ip->i_inode.i_mapping);
986 ip->i_di.di_size = size;
987 ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds();
988 ip->i_di.di_flags |= GFS2_DIF_TRUNC_IN_PROG;
989 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
990 gfs2_dinode_out(ip, dibh->b_data);
1001 static int trunc_dealloc(struct gfs2_inode *ip, u64 size)
1003 unsigned int height = ip->i_di.di_height;
1011 lblock = (size - 1) >> GFS2_SB(&ip->i_inode)->sd_sb.sb_bsize_shift;
1013 find_metapath(ip, lblock, &mp);
1016 error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1021 struct strip_mine sm;
1022 sm.sm_first = !!size;
1023 sm.sm_height = height;
1025 error = recursive_scan(ip, NULL, &mp, 0, 0, 1, do_strip, &sm);
1030 gfs2_quota_unhold(ip);
1037 static int trunc_end(struct gfs2_inode *ip)
1039 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1040 struct buffer_head *dibh;
1043 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1047 down_write(&ip->i_rw_mutex);
1049 error = gfs2_meta_inode_buffer(ip, &dibh);
1053 if (!ip->i_di.di_size) {
1054 ip->i_di.di_height = 0;
1055 ip->i_di.di_goal_meta =
1056 ip->i_di.di_goal_data =
1058 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
1060 ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds();
1061 ip->i_di.di_flags &= ~GFS2_DIF_TRUNC_IN_PROG;
1063 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1064 gfs2_dinode_out(ip, dibh->b_data);
1068 up_write(&ip->i_rw_mutex);
1069 gfs2_trans_end(sdp);
1074 * do_shrink - make a file smaller
1076 * @size: the size to make the file
1077 * @truncator: function to truncate the last partial block
1079 * Called with an exclusive lock on @ip.
1084 static int do_shrink(struct gfs2_inode *ip, u64 size)
1088 error = trunc_start(ip, size);
1094 error = trunc_dealloc(ip, size);
1096 error = trunc_end(ip);
1102 * gfs2_truncatei - make a file a given size
1104 * @size: the size to make the file
1105 * @truncator: function to truncate the last partial block
1107 * The file size can grow, shrink, or stay the same size.
1112 int gfs2_truncatei(struct gfs2_inode *ip, u64 size)
1116 if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), S_ISREG(ip->i_inode.i_mode)))
1119 if (size > ip->i_di.di_size)
1120 error = do_grow(ip, size);
1122 error = do_shrink(ip, size);
1127 int gfs2_truncatei_resume(struct gfs2_inode *ip)
1130 error = trunc_dealloc(ip, ip->i_di.di_size);
1132 error = trunc_end(ip);
1136 int gfs2_file_dealloc(struct gfs2_inode *ip)
1138 return trunc_dealloc(ip, 0);
1142 * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file
1144 * @len: the number of bytes to be written to the file
1145 * @data_blocks: returns the number of data blocks required
1146 * @ind_blocks: returns the number of indirect blocks required
1150 void gfs2_write_calc_reserv(struct gfs2_inode *ip, unsigned int len,
1151 unsigned int *data_blocks, unsigned int *ind_blocks)
1153 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1156 if (gfs2_is_dir(ip)) {
1157 *data_blocks = DIV_ROUND_UP(len, sdp->sd_jbsize) + 2;
1158 *ind_blocks = 3 * (sdp->sd_max_jheight - 1);
1160 *data_blocks = (len >> sdp->sd_sb.sb_bsize_shift) + 3;
1161 *ind_blocks = 3 * (sdp->sd_max_height - 1);
1164 for (tmp = *data_blocks; tmp > sdp->sd_diptrs;) {
1165 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
1171 * gfs2_write_alloc_required - figure out if a write will require an allocation
1172 * @ip: the file being written to
1173 * @offset: the offset to write to
1174 * @len: the number of bytes being written
1175 * @alloc_required: set to 1 if an alloc is required, 0 otherwise
1180 int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
1181 unsigned int len, int *alloc_required)
1183 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1184 u64 lblock, lblock_stop, dblock;
1189 *alloc_required = 0;
1194 if (gfs2_is_stuffed(ip)) {
1196 sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode))
1197 *alloc_required = 1;
1201 if (gfs2_is_dir(ip)) {
1202 unsigned int bsize = sdp->sd_jbsize;
1204 do_div(lblock, bsize);
1205 lblock_stop = offset + len + bsize - 1;
1206 do_div(lblock_stop, bsize);
1208 unsigned int shift = sdp->sd_sb.sb_bsize_shift;
1209 lblock = offset >> shift;
1210 lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift;
1213 for (; lblock < lblock_stop; lblock += extlen) {
1214 error = gfs2_extent_map(&ip->i_inode, lblock, &new, &dblock, &extlen);
1219 *alloc_required = 1;