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git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - fs/gfs2/bmap.c
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
;
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 di
->di_blocks
= cpu_to_be64(ip
->i_di
.di_blocks
);
169 ip
->i_di
.di_height
= 1;
170 di
->di_height
= cpu_to_be16(1);
175 up_write(&ip
->i_rw_mutex
);
180 * calc_tree_height - Calculate the height of a metadata tree
181 * @ip: The GFS2 inode
182 * @size: The proposed size of the file
184 * Work out how tall a metadata tree needs to be in order to accommodate a
185 * file of a particular size. If size is less than the current size of
186 * the inode, then the current size of the inode is used instead of the
189 * Returns: the height the tree should be
192 static unsigned int calc_tree_height(struct gfs2_inode
*ip
, u64 size
)
194 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
196 unsigned int max
, height
;
198 if (ip
->i_di
.di_size
> size
)
199 size
= ip
->i_di
.di_size
;
201 if (gfs2_is_dir(ip
)) {
202 arr
= sdp
->sd_jheightsize
;
203 max
= sdp
->sd_max_jheight
;
205 arr
= sdp
->sd_heightsize
;
206 max
= sdp
->sd_max_height
;
209 for (height
= 0; height
< max
; height
++)
210 if (arr
[height
] >= size
)
217 * build_height - Build a metadata tree of the requested height
218 * @ip: The GFS2 inode
219 * @height: The height to build to
225 static int build_height(struct inode
*inode
, unsigned height
)
227 struct gfs2_inode
*ip
= GFS2_I(inode
);
228 unsigned new_height
= height
- ip
->i_di
.di_height
;
229 struct buffer_head
*dibh
;
230 struct buffer_head
*blocks
[GFS2_MAX_META_HEIGHT
];
231 struct gfs2_dinode
*di
;
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 di
= (struct gfs2_dinode
*)dibh
->b_data
;
271 gfs2_buffer_clear_tail(dibh
, sizeof(struct gfs2_dinode
));
272 *(__be64
*)(di
+ 1) = cpu_to_be64(bn
);
273 ip
->i_di
.di_height
+= new_height
;
274 ip
->i_di
.di_blocks
+= new_height
;
275 di
->di_height
= cpu_to_be16(ip
->i_di
.di_height
);
276 di
->di_blocks
= cpu_to_be64(ip
->i_di
.di_blocks
);
282 * find_metapath - Find path through the metadata tree
283 * @ip: The inode pointer
284 * @mp: The metapath to return the result in
285 * @block: The disk block to look up
287 * This routine returns a struct metapath structure that defines a path
288 * through the metadata of inode "ip" to get to block "block".
291 * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
292 * filesystem with a blocksize of 4096.
294 * find_metapath() would return a struct metapath structure set to:
295 * mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48,
296 * and mp_list[2] = 165.
298 * That means that in order to get to the block containing the byte at
299 * offset 101342453, we would load the indirect block pointed to by pointer
300 * 0 in the dinode. We would then load the indirect block pointed to by
301 * pointer 48 in that indirect block. We would then load the data block
302 * pointed to by pointer 165 in that indirect block.
304 * ----------------------------------------
309 * ----------------------------------------
313 * ----------------------------------------
317 * |0 5 6 7 8 9 0 1 2|
318 * ----------------------------------------
322 * ----------------------------------------
327 * ----------------------------------------
331 * ----------------------------------------
332 * | Data block containing offset |
336 * ----------------------------------------
340 static void find_metapath(struct gfs2_inode
*ip
, u64 block
,
343 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
347 for (i
= ip
->i_di
.di_height
; i
--;)
348 mp
->mp_list
[i
] = do_div(b
, sdp
->sd_inptrs
);
353 * metapointer - Return pointer to start of metadata in a buffer
355 * @height: The metadata height (0 = dinode)
358 * Return a pointer to the block number of the next height of the metadata
359 * tree given a buffer containing the pointer to the current height of the
363 static inline u64
*metapointer(struct buffer_head
*bh
, int *boundary
,
364 unsigned int height
, const struct metapath
*mp
)
366 unsigned int head_size
= (height
> 0) ?
367 sizeof(struct gfs2_meta_header
) : sizeof(struct gfs2_dinode
);
370 ptr
= ((u64
*)(bh
->b_data
+ head_size
)) + mp
->mp_list
[height
];
371 if (ptr
+ 1 == (u64
*)(bh
->b_data
+ bh
->b_size
))
377 * lookup_block - Get the next metadata block in metadata tree
378 * @ip: The GFS2 inode
379 * @bh: Buffer containing the pointers to metadata blocks
380 * @height: The height of the tree (0 = dinode)
382 * @create: Non-zero if we may create a new meatdata block
383 * @new: Used to indicate if we did create a new metadata block
384 * @block: the returned disk block number
386 * Given a metatree, complete to a particular height, checks to see if the next
387 * height of the tree exists. If not the next height of the tree is created.
388 * The block number of the next height of the metadata tree is returned.
392 static int lookup_block(struct gfs2_inode
*ip
, struct buffer_head
*bh
,
393 unsigned int height
, struct metapath
*mp
, int create
,
394 int *new, u64
*block
)
397 u64
*ptr
= metapointer(bh
, &boundary
, height
, mp
);
400 *block
= be64_to_cpu(*ptr
);
409 if (height
== ip
->i_di
.di_height
- 1 && !gfs2_is_dir(ip
))
410 *block
= gfs2_alloc_data(ip
);
412 *block
= gfs2_alloc_meta(ip
);
414 gfs2_trans_add_bh(ip
->i_gl
, bh
, 1);
416 *ptr
= cpu_to_be64(*block
);
417 ip
->i_di
.di_blocks
++;
424 * gfs2_block_pointers - Map a block from an inode to a disk block
426 * @lblock: The logical block number
427 * @map_bh: The bh to be mapped
428 * @mp: metapath to use
430 * Find the block number on the current device which corresponds to an
431 * inode's block. If the block had to be created, "new" will be set.
436 static int gfs2_block_pointers(struct inode
*inode
, u64 lblock
, int create
,
437 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
;
450 unsigned int maxlen
= bh_map
->b_size
>> inode
->i_blkbits
;
454 if (gfs2_assert_warn(sdp
, !gfs2_is_stuffed(ip
)))
457 bsize
= gfs2_is_dir(ip
) ? sdp
->sd_jbsize
: sdp
->sd_sb
.sb_bsize
;
459 height
= calc_tree_height(ip
, (lblock
+ 1) * bsize
);
460 if (ip
->i_di
.di_height
< height
) {
464 error
= build_height(inode
, height
);
469 find_metapath(ip
, lblock
, mp
);
470 end_of_metadata
= ip
->i_di
.di_height
- 1;
472 error
= gfs2_meta_inode_buffer(ip
, &bh
);
476 for (x
= 0; x
< end_of_metadata
; x
++) {
477 lookup_block(ip
, bh
, x
, mp
, create
, &new, &dblock
);
482 error
= gfs2_meta_indirect_buffer(ip
, x
+1, dblock
, new, &bh
);
487 boundary
= lookup_block(ip
, bh
, end_of_metadata
, mp
, create
, &new, &dblock
);
488 clear_buffer_mapped(bh_map
);
489 clear_buffer_new(bh_map
);
490 clear_buffer_boundary(bh_map
);
493 map_bh(bh_map
, inode
->i_sb
, dblock
);
495 set_buffer_boundary(bh
);
497 struct buffer_head
*dibh
;
498 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
500 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
501 gfs2_dinode_out(&ip
->i_di
, dibh
->b_data
);
504 set_buffer_new(bh_map
);
507 while(--maxlen
&& !buffer_boundary(bh_map
)) {
510 mp
->mp_list
[end_of_metadata
]++;
511 boundary
= lookup_block(ip
, bh
, end_of_metadata
, mp
, 0, &new, &eblock
);
512 if (eblock
!= ++dblock
)
514 bh_map
->b_size
+= (1 << inode
->i_blkbits
);
516 set_buffer_boundary(bh_map
);
525 static inline void bmap_lock(struct inode
*inode
, int create
)
527 struct gfs2_inode
*ip
= GFS2_I(inode
);
529 down_write(&ip
->i_rw_mutex
);
531 down_read(&ip
->i_rw_mutex
);
534 static inline void bmap_unlock(struct inode
*inode
, int create
)
536 struct gfs2_inode
*ip
= GFS2_I(inode
);
538 up_write(&ip
->i_rw_mutex
);
540 up_read(&ip
->i_rw_mutex
);
543 int gfs2_block_map(struct inode
*inode
, u64 lblock
, int create
,
544 struct buffer_head
*bh
)
549 bmap_lock(inode
, create
);
550 ret
= gfs2_block_pointers(inode
, lblock
, create
, bh
, &mp
);
551 bmap_unlock(inode
, create
);
555 int gfs2_extent_map(struct inode
*inode
, u64 lblock
, int *new, u64
*dblock
, unsigned *extlen
)
558 struct buffer_head bh
= { .b_state
= 0, .b_blocknr
= 0 };
566 bh
.b_size
= 1 << (inode
->i_blkbits
+ 5);
567 bmap_lock(inode
, create
);
568 ret
= gfs2_block_pointers(inode
, lblock
, create
, &bh
, &mp
);
569 bmap_unlock(inode
, create
);
570 *extlen
= bh
.b_size
>> inode
->i_blkbits
;
571 *dblock
= bh
.b_blocknr
;
580 * recursive_scan - recursively scan through the end of a file
582 * @dibh: the dinode buffer
583 * @mp: the path through the metadata to the point to start
584 * @height: the height the recursion is at
585 * @block: the indirect block to look at
586 * @first: 1 if this is the first block
587 * @bc: the call to make for each piece of metadata
588 * @data: data opaque to this function to pass to @bc
590 * When this is first called @height and @block should be zero and
591 * @first should be 1.
596 static int recursive_scan(struct gfs2_inode
*ip
, struct buffer_head
*dibh
,
597 struct metapath
*mp
, unsigned int height
,
598 u64 block
, int first
, block_call_t bc
,
601 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
602 struct buffer_head
*bh
= NULL
;
606 int mh_size
= sizeof(struct gfs2_meta_header
);
609 error
= gfs2_meta_inode_buffer(ip
, &bh
);
614 top
= (u64
*)(bh
->b_data
+ sizeof(struct gfs2_dinode
)) + mp
->mp_list
[0];
615 bottom
= (u64
*)(bh
->b_data
+ sizeof(struct gfs2_dinode
)) + sdp
->sd_diptrs
;
617 error
= gfs2_meta_indirect_buffer(ip
, height
, block
, 0, &bh
);
621 top
= (u64
*)(bh
->b_data
+ mh_size
) +
622 (first
? mp
->mp_list
[height
] : 0);
624 bottom
= (u64
*)(bh
->b_data
+ mh_size
) + sdp
->sd_inptrs
;
627 error
= bc(ip
, dibh
, bh
, top
, bottom
, height
, data
);
631 if (height
< ip
->i_di
.di_height
- 1)
632 for (; top
< bottom
; top
++, first
= 0) {
636 bn
= be64_to_cpu(*top
);
638 error
= recursive_scan(ip
, dibh
, mp
, height
+ 1, bn
,
650 * do_strip - Look for a layer a particular layer of the file and strip it off
652 * @dibh: the dinode buffer
653 * @bh: A buffer of pointers
654 * @top: The first pointer in the buffer
655 * @bottom: One more than the last pointer
656 * @height: the height this buffer is at
657 * @data: a pointer to a struct strip_mine
662 static int do_strip(struct gfs2_inode
*ip
, struct buffer_head
*dibh
,
663 struct buffer_head
*bh
, u64
*top
, u64
*bottom
,
664 unsigned int height
, void *data
)
666 struct strip_mine
*sm
= data
;
667 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
668 struct gfs2_rgrp_list rlist
;
672 unsigned int rg_blocks
= 0;
674 unsigned int revokes
= 0;
681 if (height
!= sm
->sm_height
)
689 metadata
= (height
!= ip
->i_di
.di_height
- 1);
691 revokes
= (height
) ? sdp
->sd_inptrs
: sdp
->sd_diptrs
;
693 error
= gfs2_rindex_hold(sdp
, &ip
->i_alloc
.al_ri_gh
);
697 memset(&rlist
, 0, sizeof(struct gfs2_rgrp_list
));
701 for (p
= top
; p
< bottom
; p
++) {
705 bn
= be64_to_cpu(*p
);
707 if (bstart
+ blen
== bn
)
711 gfs2_rlist_add(sdp
, &rlist
, bstart
);
719 gfs2_rlist_add(sdp
, &rlist
, bstart
);
721 goto out
; /* Nothing to do */
723 gfs2_rlist_alloc(&rlist
, LM_ST_EXCLUSIVE
, 0);
725 for (x
= 0; x
< rlist
.rl_rgrps
; x
++) {
726 struct gfs2_rgrpd
*rgd
;
727 rgd
= rlist
.rl_ghs
[x
].gh_gl
->gl_object
;
728 rg_blocks
+= rgd
->rd_ri
.ri_length
;
731 error
= gfs2_glock_nq_m(rlist
.rl_rgrps
, rlist
.rl_ghs
);
735 error
= gfs2_trans_begin(sdp
, rg_blocks
+ RES_DINODE
+
736 RES_INDIRECT
+ RES_STATFS
+ RES_QUOTA
,
741 down_write(&ip
->i_rw_mutex
);
743 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
744 gfs2_trans_add_bh(ip
->i_gl
, bh
, 1);
749 for (p
= top
; p
< bottom
; p
++) {
753 bn
= be64_to_cpu(*p
);
755 if (bstart
+ blen
== bn
)
760 gfs2_free_meta(ip
, bstart
, blen
);
762 gfs2_free_data(ip
, bstart
, blen
);
770 if (!ip
->i_di
.di_blocks
)
771 gfs2_consist_inode(ip
);
772 ip
->i_di
.di_blocks
--;
776 gfs2_free_meta(ip
, bstart
, blen
);
778 gfs2_free_data(ip
, bstart
, blen
);
781 ip
->i_di
.di_mtime
= ip
->i_di
.di_ctime
= get_seconds();
783 gfs2_dinode_out(&ip
->i_di
, dibh
->b_data
);
785 up_write(&ip
->i_rw_mutex
);
790 gfs2_glock_dq_m(rlist
.rl_rgrps
, rlist
.rl_ghs
);
792 gfs2_rlist_free(&rlist
);
794 gfs2_glock_dq_uninit(&ip
->i_alloc
.al_ri_gh
);
799 * do_grow - Make a file look bigger than it is
801 * @size: the size to set the file to
803 * Called with an exclusive lock on @ip.
808 static int do_grow(struct gfs2_inode
*ip
, u64 size
)
810 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
811 struct gfs2_alloc
*al
;
812 struct buffer_head
*dibh
;
816 al
= gfs2_alloc_get(ip
);
818 error
= gfs2_quota_lock(ip
, NO_QUOTA_CHANGE
, NO_QUOTA_CHANGE
);
822 error
= gfs2_quota_check(ip
, ip
->i_di
.di_uid
, ip
->i_di
.di_gid
);
826 al
->al_requested
= sdp
->sd_max_height
+ RES_DATA
;
828 error
= gfs2_inplace_reserve(ip
);
832 error
= gfs2_trans_begin(sdp
,
833 sdp
->sd_max_height
+ al
->al_rgd
->rd_ri
.ri_length
+
834 RES_JDATA
+ RES_DINODE
+ RES_STATFS
+ RES_QUOTA
, 0);
838 if (size
> sdp
->sd_sb
.sb_bsize
- sizeof(struct gfs2_dinode
)) {
839 if (gfs2_is_stuffed(ip
)) {
840 error
= gfs2_unstuff_dinode(ip
, NULL
);
845 h
= calc_tree_height(ip
, size
);
846 if (ip
->i_di
.di_height
< h
) {
847 down_write(&ip
->i_rw_mutex
);
848 error
= build_height(&ip
->i_inode
, h
);
849 up_write(&ip
->i_rw_mutex
);
855 ip
->i_di
.di_size
= size
;
856 ip
->i_di
.di_mtime
= ip
->i_di
.di_ctime
= get_seconds();
858 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
862 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
863 gfs2_dinode_out(&ip
->i_di
, dibh
->b_data
);
869 gfs2_inplace_release(ip
);
871 gfs2_quota_unlock(ip
);
879 * gfs2_block_truncate_page - Deal with zeroing out data for truncate
881 * This is partly borrowed from ext3.
883 static int gfs2_block_truncate_page(struct address_space
*mapping
)
885 struct inode
*inode
= mapping
->host
;
886 struct gfs2_inode
*ip
= GFS2_I(inode
);
887 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
888 loff_t from
= inode
->i_size
;
889 unsigned long index
= from
>> PAGE_CACHE_SHIFT
;
890 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
891 unsigned blocksize
, iblock
, length
, pos
;
892 struct buffer_head
*bh
;
897 page
= grab_cache_page(mapping
, index
);
901 blocksize
= inode
->i_sb
->s_blocksize
;
902 length
= blocksize
- (offset
& (blocksize
- 1));
903 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
905 if (!page_has_buffers(page
))
906 create_empty_buffers(page
, blocksize
, 0);
908 /* Find the buffer that contains "offset" */
909 bh
= page_buffers(page
);
911 while (offset
>= pos
) {
912 bh
= bh
->b_this_page
;
919 if (!buffer_mapped(bh
)) {
920 gfs2_get_block(inode
, iblock
, bh
, 0);
921 /* unmapped? It's a hole - nothing to do */
922 if (!buffer_mapped(bh
))
926 /* Ok, it's mapped. Make sure it's up-to-date */
927 if (PageUptodate(page
))
928 set_buffer_uptodate(bh
);
930 if (!buffer_uptodate(bh
)) {
932 ll_rw_block(READ
, 1, &bh
);
934 /* Uhhuh. Read error. Complain and punt. */
935 if (!buffer_uptodate(bh
))
939 if (sdp
->sd_args
.ar_data
== GFS2_DATA_ORDERED
|| gfs2_is_jdata(ip
))
940 gfs2_trans_add_bh(ip
->i_gl
, bh
, 0);
942 kaddr
= kmap_atomic(page
, KM_USER0
);
943 memset(kaddr
+ offset
, 0, length
);
944 flush_dcache_page(page
);
945 kunmap_atomic(kaddr
, KM_USER0
);
949 page_cache_release(page
);
953 static int trunc_start(struct gfs2_inode
*ip
, u64 size
)
955 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
956 struct buffer_head
*dibh
;
957 int journaled
= gfs2_is_jdata(ip
);
960 error
= gfs2_trans_begin(sdp
,
961 RES_DINODE
+ (journaled
? RES_JDATA
: 0), 0);
965 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
969 if (gfs2_is_stuffed(ip
)) {
970 ip
->i_di
.di_size
= size
;
971 ip
->i_di
.di_mtime
= ip
->i_di
.di_ctime
= get_seconds();
972 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
973 gfs2_dinode_out(&ip
->i_di
, dibh
->b_data
);
974 gfs2_buffer_clear_tail(dibh
, sizeof(struct gfs2_dinode
) + size
);
978 if (size
& (u64
)(sdp
->sd_sb
.sb_bsize
- 1))
979 error
= gfs2_block_truncate_page(ip
->i_inode
.i_mapping
);
982 ip
->i_di
.di_size
= size
;
983 ip
->i_di
.di_mtime
= ip
->i_di
.di_ctime
= get_seconds();
984 ip
->i_di
.di_flags
|= GFS2_DIF_TRUNC_IN_PROG
;
985 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
986 gfs2_dinode_out(&ip
->i_di
, dibh
->b_data
);
997 static int trunc_dealloc(struct gfs2_inode
*ip
, u64 size
)
999 unsigned int height
= ip
->i_di
.di_height
;
1007 lblock
= (size
- 1) >> GFS2_SB(&ip
->i_inode
)->sd_sb
.sb_bsize_shift
;
1009 find_metapath(ip
, lblock
, &mp
);
1012 error
= gfs2_quota_hold(ip
, NO_QUOTA_CHANGE
, NO_QUOTA_CHANGE
);
1017 struct strip_mine sm
;
1018 sm
.sm_first
= !!size
;
1019 sm
.sm_height
= height
;
1021 error
= recursive_scan(ip
, NULL
, &mp
, 0, 0, 1, do_strip
, &sm
);
1026 gfs2_quota_unhold(ip
);
1033 static int trunc_end(struct gfs2_inode
*ip
)
1035 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1036 struct buffer_head
*dibh
;
1039 error
= gfs2_trans_begin(sdp
, RES_DINODE
, 0);
1043 down_write(&ip
->i_rw_mutex
);
1045 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
1049 if (!ip
->i_di
.di_size
) {
1050 ip
->i_di
.di_height
= 0;
1051 ip
->i_di
.di_goal_meta
=
1052 ip
->i_di
.di_goal_data
=
1054 gfs2_buffer_clear_tail(dibh
, sizeof(struct gfs2_dinode
));
1056 ip
->i_di
.di_mtime
= ip
->i_di
.di_ctime
= get_seconds();
1057 ip
->i_di
.di_flags
&= ~GFS2_DIF_TRUNC_IN_PROG
;
1059 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
1060 gfs2_dinode_out(&ip
->i_di
, dibh
->b_data
);
1064 up_write(&ip
->i_rw_mutex
);
1065 gfs2_trans_end(sdp
);
1070 * do_shrink - make a file smaller
1072 * @size: the size to make the file
1073 * @truncator: function to truncate the last partial block
1075 * Called with an exclusive lock on @ip.
1080 static int do_shrink(struct gfs2_inode
*ip
, u64 size
)
1084 error
= trunc_start(ip
, size
);
1090 error
= trunc_dealloc(ip
, size
);
1092 error
= trunc_end(ip
);
1098 * gfs2_truncatei - make a file a given size
1100 * @size: the size to make the file
1101 * @truncator: function to truncate the last partial block
1103 * The file size can grow, shrink, or stay the same size.
1108 int gfs2_truncatei(struct gfs2_inode
*ip
, u64 size
)
1112 if (gfs2_assert_warn(GFS2_SB(&ip
->i_inode
), S_ISREG(ip
->i_di
.di_mode
)))
1115 if (size
> ip
->i_di
.di_size
)
1116 error
= do_grow(ip
, size
);
1118 error
= do_shrink(ip
, size
);
1123 int gfs2_truncatei_resume(struct gfs2_inode
*ip
)
1126 error
= trunc_dealloc(ip
, ip
->i_di
.di_size
);
1128 error
= trunc_end(ip
);
1132 int gfs2_file_dealloc(struct gfs2_inode
*ip
)
1134 return trunc_dealloc(ip
, 0);
1138 * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file
1140 * @len: the number of bytes to be written to the file
1141 * @data_blocks: returns the number of data blocks required
1142 * @ind_blocks: returns the number of indirect blocks required
1146 void gfs2_write_calc_reserv(struct gfs2_inode
*ip
, unsigned int len
,
1147 unsigned int *data_blocks
, unsigned int *ind_blocks
)
1149 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1152 if (gfs2_is_dir(ip
)) {
1153 *data_blocks
= DIV_ROUND_UP(len
, sdp
->sd_jbsize
) + 2;
1154 *ind_blocks
= 3 * (sdp
->sd_max_jheight
- 1);
1156 *data_blocks
= (len
>> sdp
->sd_sb
.sb_bsize_shift
) + 3;
1157 *ind_blocks
= 3 * (sdp
->sd_max_height
- 1);
1160 for (tmp
= *data_blocks
; tmp
> sdp
->sd_diptrs
;) {
1161 tmp
= DIV_ROUND_UP(tmp
, sdp
->sd_inptrs
);
1167 * gfs2_write_alloc_required - figure out if a write will require an allocation
1168 * @ip: the file being written to
1169 * @offset: the offset to write to
1170 * @len: the number of bytes being written
1171 * @alloc_required: set to 1 if an alloc is required, 0 otherwise
1176 int gfs2_write_alloc_required(struct gfs2_inode
*ip
, u64 offset
,
1177 unsigned int len
, int *alloc_required
)
1179 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1180 u64 lblock
, lblock_stop
, dblock
;
1185 *alloc_required
= 0;
1190 if (gfs2_is_stuffed(ip
)) {
1192 sdp
->sd_sb
.sb_bsize
- sizeof(struct gfs2_dinode
))
1193 *alloc_required
= 1;
1197 if (gfs2_is_dir(ip
)) {
1198 unsigned int bsize
= sdp
->sd_jbsize
;
1200 do_div(lblock
, bsize
);
1201 lblock_stop
= offset
+ len
+ bsize
- 1;
1202 do_div(lblock_stop
, bsize
);
1204 unsigned int shift
= sdp
->sd_sb
.sb_bsize_shift
;
1205 lblock
= offset
>> shift
;
1206 lblock_stop
= (offset
+ len
+ sdp
->sd_sb
.sb_bsize
- 1) >> shift
;
1209 for (; lblock
< lblock_stop
; lblock
+= extlen
) {
1210 error
= gfs2_extent_map(&ip
->i_inode
, lblock
, &new, &dblock
, &extlen
);
1215 *alloc_required
= 1;