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/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/gfs2_ondisk.h>
15 #include <linux/crc32.h>
16 #include <trace/events/gfs2.h>
30 /* This doesn't need to be that large as max 64 bit pointers in a 4k
31 * block is 512, so __u16 is fine for that. It saves stack space to
35 struct buffer_head
*mp_bh
[GFS2_MAX_META_HEIGHT
];
36 __u16 mp_list
[GFS2_MAX_META_HEIGHT
];
39 typedef int (*block_call_t
) (struct gfs2_inode
*ip
, struct buffer_head
*dibh
,
40 struct buffer_head
*bh
, __be64
*top
,
41 __be64
*bottom
, unsigned int height
,
46 unsigned int sm_height
;
50 * gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page
52 * @dibh: the dinode buffer
53 * @block: the block number that was allocated
54 * @private: any locked page held by the caller process
59 static int gfs2_unstuffer_page(struct gfs2_inode
*ip
, struct buffer_head
*dibh
,
60 u64 block
, struct page
*page
)
62 struct inode
*inode
= &ip
->i_inode
;
63 struct buffer_head
*bh
;
66 if (!page
|| page
->index
) {
67 page
= grab_cache_page(inode
->i_mapping
, 0);
73 if (!PageUptodate(page
)) {
74 void *kaddr
= kmap(page
);
76 memcpy(kaddr
, dibh
->b_data
+ sizeof(struct gfs2_dinode
),
78 memset(kaddr
+ ip
->i_disksize
, 0,
79 PAGE_CACHE_SIZE
- ip
->i_disksize
);
82 SetPageUptodate(page
);
85 if (!page_has_buffers(page
))
86 create_empty_buffers(page
, 1 << inode
->i_blkbits
,
89 bh
= page_buffers(page
);
91 if (!buffer_mapped(bh
))
92 map_bh(bh
, inode
->i_sb
, block
);
94 set_buffer_uptodate(bh
);
95 if (!gfs2_is_jdata(ip
))
96 mark_buffer_dirty(bh
);
97 if (!gfs2_is_writeback(ip
))
98 gfs2_trans_add_bh(ip
->i_gl
, bh
, 0);
102 page_cache_release(page
);
109 * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big
110 * @ip: The GFS2 inode to unstuff
111 * @unstuffer: the routine that handles unstuffing a non-zero length file
112 * @private: private data for the unstuffer
114 * This routine unstuffs a dinode and returns it to a "normal" state such
115 * that the height can be grown in the traditional way.
120 int gfs2_unstuff_dinode(struct gfs2_inode
*ip
, struct page
*page
)
122 struct buffer_head
*bh
, *dibh
;
123 struct gfs2_dinode
*di
;
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_disksize
) {
135 /* Get a free block, fill it with the stuffed data,
136 and write it out to disk */
139 error
= gfs2_alloc_block(ip
, &block
, &n
);
143 gfs2_trans_add_unrevoke(GFS2_SB(&ip
->i_inode
), block
, 1);
144 error
= gfs2_dir_get_new_buffer(ip
, block
, &bh
);
147 gfs2_buffer_copy_tail(bh
, sizeof(struct gfs2_meta_header
),
148 dibh
, sizeof(struct gfs2_dinode
));
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_disksize
) {
164 *(__be64
*)(di
+ 1) = cpu_to_be64(block
);
165 gfs2_add_inode_blocks(&ip
->i_inode
, 1);
166 di
->di_blocks
= cpu_to_be64(gfs2_get_inode_blocks(&ip
->i_inode
));
170 di
->di_height
= cpu_to_be16(1);
175 up_write(&ip
->i_rw_mutex
);
181 * find_metapath - Find path through the metadata tree
182 * @sdp: The superblock
183 * @mp: The metapath to return the result in
184 * @block: The disk block to look up
185 * @height: The pre-calculated height of the metadata tree
187 * This routine returns a struct metapath structure that defines a path
188 * through the metadata of inode "ip" to get to block "block".
191 * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
192 * filesystem with a blocksize of 4096.
194 * find_metapath() would return a struct metapath structure set to:
195 * mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48,
196 * and mp_list[2] = 165.
198 * That means that in order to get to the block containing the byte at
199 * offset 101342453, we would load the indirect block pointed to by pointer
200 * 0 in the dinode. We would then load the indirect block pointed to by
201 * pointer 48 in that indirect block. We would then load the data block
202 * pointed to by pointer 165 in that indirect block.
204 * ----------------------------------------
209 * ----------------------------------------
213 * ----------------------------------------
217 * |0 5 6 7 8 9 0 1 2|
218 * ----------------------------------------
222 * ----------------------------------------
227 * ----------------------------------------
231 * ----------------------------------------
232 * | Data block containing offset |
236 * ----------------------------------------
240 static void find_metapath(const struct gfs2_sbd
*sdp
, u64 block
,
241 struct metapath
*mp
, unsigned int height
)
245 for (i
= height
; i
--;)
246 mp
->mp_list
[i
] = do_div(block
, sdp
->sd_inptrs
);
250 static inline unsigned int metapath_branch_start(const struct metapath
*mp
)
252 if (mp
->mp_list
[0] == 0)
258 * metapointer - Return pointer to start of metadata in a buffer
259 * @height: The metadata height (0 = dinode)
262 * Return a pointer to the block number of the next height of the metadata
263 * tree given a buffer containing the pointer to the current height of the
267 static inline __be64
*metapointer(unsigned int height
, const struct metapath
*mp
)
269 struct buffer_head
*bh
= mp
->mp_bh
[height
];
270 unsigned int head_size
= (height
> 0) ?
271 sizeof(struct gfs2_meta_header
) : sizeof(struct gfs2_dinode
);
272 return ((__be64
*)(bh
->b_data
+ head_size
)) + mp
->mp_list
[height
];
276 * lookup_metapath - Walk the metadata tree to a specific point
280 * Assumes that the inode's buffer has already been looked up and
281 * hooked onto mp->mp_bh[0] and that the metapath has been initialised
282 * by find_metapath().
284 * If this function encounters part of the tree which has not been
285 * allocated, it returns the current height of the tree at the point
286 * at which it found the unallocated block. Blocks which are found are
287 * added to the mp->mp_bh[] list.
289 * Returns: error or height of metadata tree
292 static int lookup_metapath(struct gfs2_inode
*ip
, struct metapath
*mp
)
294 unsigned int end_of_metadata
= ip
->i_height
- 1;
300 for (x
= 0; x
< end_of_metadata
; x
++) {
301 ptr
= metapointer(x
, mp
);
302 dblock
= be64_to_cpu(*ptr
);
306 ret
= gfs2_meta_indirect_buffer(ip
, x
+1, dblock
, 0, &mp
->mp_bh
[x
+1]);
314 static inline void release_metapath(struct metapath
*mp
)
318 for (i
= 0; i
< GFS2_MAX_META_HEIGHT
; i
++) {
319 if (mp
->mp_bh
[i
] == NULL
)
321 brelse(mp
->mp_bh
[i
]);
326 * gfs2_extent_length - Returns length of an extent of blocks
327 * @start: Start of the buffer
328 * @len: Length of the buffer in bytes
329 * @ptr: Current position in the buffer
330 * @limit: Max extent length to return (0 = unlimited)
331 * @eob: Set to 1 if we hit "end of block"
333 * If the first block is zero (unallocated) it will return the number of
334 * unallocated blocks in the extent, otherwise it will return the number
335 * of contiguous blocks in the extent.
337 * Returns: The length of the extent (minimum of one block)
340 static inline unsigned int gfs2_extent_length(void *start
, unsigned int len
, __be64
*ptr
, unsigned limit
, int *eob
)
342 const __be64
*end
= (start
+ len
);
343 const __be64
*first
= ptr
;
344 u64 d
= be64_to_cpu(*ptr
);
351 if (limit
&& --limit
== 0)
355 } while(be64_to_cpu(*ptr
) == d
);
358 return (ptr
- first
);
361 static inline void bmap_lock(struct gfs2_inode
*ip
, int create
)
364 down_write(&ip
->i_rw_mutex
);
366 down_read(&ip
->i_rw_mutex
);
369 static inline void bmap_unlock(struct gfs2_inode
*ip
, int create
)
372 up_write(&ip
->i_rw_mutex
);
374 up_read(&ip
->i_rw_mutex
);
377 static inline __be64
*gfs2_indirect_init(struct metapath
*mp
,
378 struct gfs2_glock
*gl
, unsigned int i
,
379 unsigned offset
, u64 bn
)
381 __be64
*ptr
= (__be64
*)(mp
->mp_bh
[i
- 1]->b_data
+
382 ((i
> 1) ? sizeof(struct gfs2_meta_header
) :
383 sizeof(struct gfs2_dinode
)));
385 BUG_ON(mp
->mp_bh
[i
] != NULL
);
386 mp
->mp_bh
[i
] = gfs2_meta_new(gl
, bn
);
387 gfs2_trans_add_bh(gl
, mp
->mp_bh
[i
], 1);
388 gfs2_metatype_set(mp
->mp_bh
[i
], GFS2_METATYPE_IN
, GFS2_FORMAT_IN
);
389 gfs2_buffer_clear_tail(mp
->mp_bh
[i
], sizeof(struct gfs2_meta_header
));
391 *ptr
= cpu_to_be64(bn
);
397 ALLOC_GROW_DEPTH
= 1,
398 ALLOC_GROW_HEIGHT
= 2,
399 /* ALLOC_UNSTUFF = 3, TBD and rather complicated */
403 * gfs2_bmap_alloc - Build a metadata tree of the requested height
404 * @inode: The GFS2 inode
405 * @lblock: The logical starting block of the extent
406 * @bh_map: This is used to return the mapping details
408 * @sheight: The starting height (i.e. whats already mapped)
409 * @height: The height to build to
410 * @maxlen: The max number of data blocks to alloc
412 * In this routine we may have to alloc:
413 * i) Indirect blocks to grow the metadata tree height
414 * ii) Indirect blocks to fill in lower part of the metadata tree
417 * The function is in two parts. The first part works out the total
418 * number of blocks which we need. The second part does the actual
419 * allocation asking for an extent at a time (if enough contiguous free
420 * blocks are available, there will only be one request per bmap call)
421 * and uses the state machine to initialise the blocks in order.
423 * Returns: errno on error
426 static int gfs2_bmap_alloc(struct inode
*inode
, const sector_t lblock
,
427 struct buffer_head
*bh_map
, struct metapath
*mp
,
428 const unsigned int sheight
,
429 const unsigned int height
,
430 const unsigned int maxlen
)
432 struct gfs2_inode
*ip
= GFS2_I(inode
);
433 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
434 struct buffer_head
*dibh
= mp
->mp_bh
[0];
436 unsigned n
, i
, blks
, alloced
= 0, iblks
= 0, branch_start
= 0;
438 unsigned ptrs_per_blk
;
439 const unsigned end_of_metadata
= height
- 1;
441 enum alloc_state state
;
446 BUG_ON(dibh
== NULL
);
448 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
450 if (height
== sheight
) {
451 struct buffer_head
*bh
;
452 /* Bottom indirect block exists, find unalloced extent size */
453 ptr
= metapointer(end_of_metadata
, mp
);
454 bh
= mp
->mp_bh
[end_of_metadata
];
455 dblks
= gfs2_extent_length(bh
->b_data
, bh
->b_size
, ptr
, maxlen
,
460 /* Need to allocate indirect blocks */
461 ptrs_per_blk
= height
> 1 ? sdp
->sd_inptrs
: sdp
->sd_diptrs
;
462 dblks
= min(maxlen
, ptrs_per_blk
- mp
->mp_list
[end_of_metadata
]);
463 if (height
== ip
->i_height
) {
464 /* Writing into existing tree, extend tree down */
465 iblks
= height
- sheight
;
466 state
= ALLOC_GROW_DEPTH
;
468 /* Building up tree height */
469 state
= ALLOC_GROW_HEIGHT
;
470 iblks
= height
- ip
->i_height
;
471 branch_start
= metapath_branch_start(mp
);
472 iblks
+= (height
- branch_start
);
476 /* start of the second part of the function (state machine) */
478 blks
= dblks
+ iblks
;
483 error
= gfs2_alloc_block(ip
, &bn
, &n
);
487 if (state
!= ALLOC_DATA
|| gfs2_is_jdata(ip
))
488 gfs2_trans_add_unrevoke(sdp
, bn
, n
);
490 /* Growing height of tree */
491 case ALLOC_GROW_HEIGHT
:
493 ptr
= (__be64
*)(dibh
->b_data
+
494 sizeof(struct gfs2_dinode
));
497 for (; i
- 1 < height
- ip
->i_height
&& n
> 0; i
++, n
--)
498 gfs2_indirect_init(mp
, ip
->i_gl
, i
, 0, bn
++);
499 if (i
- 1 == height
- ip
->i_height
) {
501 gfs2_buffer_copy_tail(mp
->mp_bh
[i
],
502 sizeof(struct gfs2_meta_header
),
503 dibh
, sizeof(struct gfs2_dinode
));
504 gfs2_buffer_clear_tail(dibh
,
505 sizeof(struct gfs2_dinode
) +
507 ptr
= (__be64
*)(mp
->mp_bh
[i
]->b_data
+
508 sizeof(struct gfs2_meta_header
));
510 state
= ALLOC_GROW_DEPTH
;
511 for(i
= branch_start
; i
< height
; i
++) {
512 if (mp
->mp_bh
[i
] == NULL
)
514 brelse(mp
->mp_bh
[i
]);
521 /* Branching from existing tree */
522 case ALLOC_GROW_DEPTH
:
523 if (i
> 1 && i
< height
)
524 gfs2_trans_add_bh(ip
->i_gl
, mp
->mp_bh
[i
-1], 1);
525 for (; i
< height
&& n
> 0; i
++, n
--)
526 gfs2_indirect_init(mp
, ip
->i_gl
, i
,
527 mp
->mp_list
[i
-1], bn
++);
532 /* Tree complete, adding data blocks */
535 BUG_ON(mp
->mp_bh
[end_of_metadata
] == NULL
);
536 gfs2_trans_add_bh(ip
->i_gl
, mp
->mp_bh
[end_of_metadata
], 1);
538 ptr
= metapointer(end_of_metadata
, mp
);
541 *ptr
++ = cpu_to_be64(bn
++);
544 } while (state
!= ALLOC_DATA
);
546 ip
->i_height
= height
;
547 gfs2_add_inode_blocks(&ip
->i_inode
, alloced
);
548 gfs2_dinode_out(ip
, mp
->mp_bh
[0]->b_data
);
549 map_bh(bh_map
, inode
->i_sb
, dblock
);
550 bh_map
->b_size
= dblks
<< inode
->i_blkbits
;
551 set_buffer_new(bh_map
);
556 * gfs2_block_map - Map a block from an inode to a disk block
558 * @lblock: The logical block number
559 * @bh_map: The bh to be mapped
560 * @create: True if its ok to alloc blocks to satify the request
562 * Sets buffer_mapped() if successful, sets buffer_boundary() if a
563 * read of metadata will be required before the next block can be
564 * mapped. Sets buffer_new() if new blocks were allocated.
569 int gfs2_block_map(struct inode
*inode
, sector_t lblock
,
570 struct buffer_head
*bh_map
, int create
)
572 struct gfs2_inode
*ip
= GFS2_I(inode
);
573 struct gfs2_sbd
*sdp
= GFS2_SB(inode
);
574 unsigned int bsize
= sdp
->sd_sb
.sb_bsize
;
575 const unsigned int maxlen
= bh_map
->b_size
>> inode
->i_blkbits
;
576 const u64
*arr
= sdp
->sd_heightsize
;
583 struct buffer_head
*bh
;
588 memset(mp
.mp_bh
, 0, sizeof(mp
.mp_bh
));
589 bmap_lock(ip
, create
);
590 clear_buffer_mapped(bh_map
);
591 clear_buffer_new(bh_map
);
592 clear_buffer_boundary(bh_map
);
593 trace_gfs2_bmap(ip
, bh_map
, lblock
, create
, 1);
594 if (gfs2_is_dir(ip
)) {
595 bsize
= sdp
->sd_jbsize
;
596 arr
= sdp
->sd_jheightsize
;
599 ret
= gfs2_meta_inode_buffer(ip
, &mp
.mp_bh
[0]);
603 height
= ip
->i_height
;
604 size
= (lblock
+ 1) * bsize
;
605 while (size
> arr
[height
])
607 find_metapath(sdp
, lblock
, &mp
, height
);
609 if (height
> ip
->i_height
|| gfs2_is_stuffed(ip
))
611 ret
= lookup_metapath(ip
, &mp
);
614 if (ret
!= ip
->i_height
)
616 ptr
= metapointer(ip
->i_height
- 1, &mp
);
619 map_bh(bh_map
, inode
->i_sb
, be64_to_cpu(*ptr
));
620 bh
= mp
.mp_bh
[ip
->i_height
- 1];
621 len
= gfs2_extent_length(bh
->b_data
, bh
->b_size
, ptr
, maxlen
, &eob
);
622 bh_map
->b_size
= (len
<< inode
->i_blkbits
);
624 set_buffer_boundary(bh_map
);
627 release_metapath(&mp
);
628 trace_gfs2_bmap(ip
, bh_map
, lblock
, create
, ret
);
629 bmap_unlock(ip
, create
);
633 /* All allocations are done here, firstly check create flag */
635 BUG_ON(gfs2_is_stuffed(ip
));
640 /* At this point ret is the tree depth of already allocated blocks */
641 ret
= gfs2_bmap_alloc(inode
, lblock
, bh_map
, &mp
, ret
, height
, maxlen
);
646 * Deprecated: do not use in new code
648 int gfs2_extent_map(struct inode
*inode
, u64 lblock
, int *new, u64
*dblock
, unsigned *extlen
)
650 struct buffer_head bh
= { .b_state
= 0, .b_blocknr
= 0 };
658 bh
.b_size
= 1 << (inode
->i_blkbits
+ (create
? 0 : 5));
659 ret
= gfs2_block_map(inode
, lblock
, &bh
, create
);
660 *extlen
= bh
.b_size
>> inode
->i_blkbits
;
661 *dblock
= bh
.b_blocknr
;
670 * recursive_scan - recursively scan through the end of a file
672 * @dibh: the dinode buffer
673 * @mp: the path through the metadata to the point to start
674 * @height: the height the recursion is at
675 * @block: the indirect block to look at
676 * @first: 1 if this is the first block
677 * @bc: the call to make for each piece of metadata
678 * @data: data opaque to this function to pass to @bc
680 * When this is first called @height and @block should be zero and
681 * @first should be 1.
686 static int recursive_scan(struct gfs2_inode
*ip
, struct buffer_head
*dibh
,
687 struct metapath
*mp
, unsigned int height
,
688 u64 block
, int first
, block_call_t bc
,
691 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
692 struct buffer_head
*bh
= NULL
;
693 __be64
*top
, *bottom
;
696 int mh_size
= sizeof(struct gfs2_meta_header
);
699 error
= gfs2_meta_inode_buffer(ip
, &bh
);
704 top
= (__be64
*)(bh
->b_data
+ sizeof(struct gfs2_dinode
)) + mp
->mp_list
[0];
705 bottom
= (__be64
*)(bh
->b_data
+ sizeof(struct gfs2_dinode
)) + sdp
->sd_diptrs
;
707 error
= gfs2_meta_indirect_buffer(ip
, height
, block
, 0, &bh
);
711 top
= (__be64
*)(bh
->b_data
+ mh_size
) +
712 (first
? mp
->mp_list
[height
] : 0);
714 bottom
= (__be64
*)(bh
->b_data
+ mh_size
) + sdp
->sd_inptrs
;
717 error
= bc(ip
, dibh
, bh
, top
, bottom
, height
, data
);
721 if (height
< ip
->i_height
- 1)
722 for (; top
< bottom
; top
++, first
= 0) {
726 bn
= be64_to_cpu(*top
);
728 error
= recursive_scan(ip
, dibh
, mp
, height
+ 1, bn
,
740 * do_strip - Look for a layer a particular layer of the file and strip it off
742 * @dibh: the dinode buffer
743 * @bh: A buffer of pointers
744 * @top: The first pointer in the buffer
745 * @bottom: One more than the last pointer
746 * @height: the height this buffer is at
747 * @data: a pointer to a struct strip_mine
752 static int do_strip(struct gfs2_inode
*ip
, struct buffer_head
*dibh
,
753 struct buffer_head
*bh
, __be64
*top
, __be64
*bottom
,
754 unsigned int height
, void *data
)
756 struct strip_mine
*sm
= data
;
757 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
758 struct gfs2_rgrp_list rlist
;
762 unsigned int rg_blocks
= 0;
764 unsigned int revokes
= 0;
771 if (height
!= sm
->sm_height
)
779 metadata
= (height
!= ip
->i_height
- 1);
781 revokes
= (height
) ? sdp
->sd_inptrs
: sdp
->sd_diptrs
;
783 error
= gfs2_rindex_hold(sdp
, &ip
->i_alloc
->al_ri_gh
);
787 memset(&rlist
, 0, sizeof(struct gfs2_rgrp_list
));
791 for (p
= top
; p
< bottom
; p
++) {
795 bn
= be64_to_cpu(*p
);
797 if (bstart
+ blen
== bn
)
801 gfs2_rlist_add(sdp
, &rlist
, bstart
);
809 gfs2_rlist_add(sdp
, &rlist
, bstart
);
811 goto out
; /* Nothing to do */
813 gfs2_rlist_alloc(&rlist
, LM_ST_EXCLUSIVE
);
815 for (x
= 0; x
< rlist
.rl_rgrps
; x
++) {
816 struct gfs2_rgrpd
*rgd
;
817 rgd
= rlist
.rl_ghs
[x
].gh_gl
->gl_object
;
818 rg_blocks
+= rgd
->rd_length
;
821 error
= gfs2_glock_nq_m(rlist
.rl_rgrps
, rlist
.rl_ghs
);
825 error
= gfs2_trans_begin(sdp
, rg_blocks
+ RES_DINODE
+
826 RES_INDIRECT
+ RES_STATFS
+ RES_QUOTA
,
831 down_write(&ip
->i_rw_mutex
);
833 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
834 gfs2_trans_add_bh(ip
->i_gl
, bh
, 1);
839 for (p
= top
; p
< bottom
; p
++) {
843 bn
= be64_to_cpu(*p
);
845 if (bstart
+ blen
== bn
)
850 gfs2_free_meta(ip
, bstart
, blen
);
852 gfs2_free_data(ip
, bstart
, blen
);
860 gfs2_add_inode_blocks(&ip
->i_inode
, -1);
864 gfs2_free_meta(ip
, bstart
, blen
);
866 gfs2_free_data(ip
, bstart
, blen
);
869 ip
->i_inode
.i_mtime
= ip
->i_inode
.i_ctime
= CURRENT_TIME
;
871 gfs2_dinode_out(ip
, dibh
->b_data
);
873 up_write(&ip
->i_rw_mutex
);
878 gfs2_glock_dq_m(rlist
.rl_rgrps
, rlist
.rl_ghs
);
880 gfs2_rlist_free(&rlist
);
882 gfs2_glock_dq_uninit(&ip
->i_alloc
->al_ri_gh
);
887 * do_grow - Make a file look bigger than it is
889 * @size: the size to set the file to
891 * Called with an exclusive lock on @ip.
896 static int do_grow(struct gfs2_inode
*ip
, u64 size
)
898 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
899 struct gfs2_alloc
*al
;
900 struct buffer_head
*dibh
;
903 al
= gfs2_alloc_get(ip
);
907 error
= gfs2_quota_lock_check(ip
);
911 al
->al_requested
= sdp
->sd_max_height
+ RES_DATA
;
913 error
= gfs2_inplace_reserve(ip
);
917 error
= gfs2_trans_begin(sdp
,
918 sdp
->sd_max_height
+ al
->al_rgd
->rd_length
+
919 RES_JDATA
+ RES_DINODE
+ RES_STATFS
+ RES_QUOTA
, 0);
923 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
927 if (size
> sdp
->sd_sb
.sb_bsize
- sizeof(struct gfs2_dinode
)) {
928 if (gfs2_is_stuffed(ip
)) {
929 error
= gfs2_unstuff_dinode(ip
, NULL
);
935 ip
->i_disksize
= size
;
936 ip
->i_inode
.i_mtime
= ip
->i_inode
.i_ctime
= CURRENT_TIME
;
937 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
938 gfs2_dinode_out(ip
, dibh
->b_data
);
945 gfs2_inplace_release(ip
);
947 gfs2_quota_unlock(ip
);
955 * gfs2_block_truncate_page - Deal with zeroing out data for truncate
957 * This is partly borrowed from ext3.
959 static int gfs2_block_truncate_page(struct address_space
*mapping
)
961 struct inode
*inode
= mapping
->host
;
962 struct gfs2_inode
*ip
= GFS2_I(inode
);
963 loff_t from
= inode
->i_size
;
964 unsigned long index
= from
>> PAGE_CACHE_SHIFT
;
965 unsigned offset
= from
& (PAGE_CACHE_SIZE
-1);
966 unsigned blocksize
, iblock
, length
, pos
;
967 struct buffer_head
*bh
;
971 page
= grab_cache_page(mapping
, index
);
975 blocksize
= inode
->i_sb
->s_blocksize
;
976 length
= blocksize
- (offset
& (blocksize
- 1));
977 iblock
= index
<< (PAGE_CACHE_SHIFT
- inode
->i_sb
->s_blocksize_bits
);
979 if (!page_has_buffers(page
))
980 create_empty_buffers(page
, blocksize
, 0);
982 /* Find the buffer that contains "offset" */
983 bh
= page_buffers(page
);
985 while (offset
>= pos
) {
986 bh
= bh
->b_this_page
;
993 if (!buffer_mapped(bh
)) {
994 gfs2_block_map(inode
, iblock
, bh
, 0);
995 /* unmapped? It's a hole - nothing to do */
996 if (!buffer_mapped(bh
))
1000 /* Ok, it's mapped. Make sure it's up-to-date */
1001 if (PageUptodate(page
))
1002 set_buffer_uptodate(bh
);
1004 if (!buffer_uptodate(bh
)) {
1006 ll_rw_block(READ
, 1, &bh
);
1008 /* Uhhuh. Read error. Complain and punt. */
1009 if (!buffer_uptodate(bh
))
1014 if (!gfs2_is_writeback(ip
))
1015 gfs2_trans_add_bh(ip
->i_gl
, bh
, 0);
1017 zero_user(page
, offset
, length
);
1018 mark_buffer_dirty(bh
);
1021 page_cache_release(page
);
1025 static int trunc_start(struct gfs2_inode
*ip
, u64 size
)
1027 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1028 struct buffer_head
*dibh
;
1029 int journaled
= gfs2_is_jdata(ip
);
1032 error
= gfs2_trans_begin(sdp
,
1033 RES_DINODE
+ (journaled
? RES_JDATA
: 0), 0);
1037 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
1041 if (gfs2_is_stuffed(ip
)) {
1042 ip
->i_disksize
= size
;
1043 ip
->i_inode
.i_mtime
= ip
->i_inode
.i_ctime
= CURRENT_TIME
;
1044 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
1045 gfs2_dinode_out(ip
, dibh
->b_data
);
1046 gfs2_buffer_clear_tail(dibh
, sizeof(struct gfs2_dinode
) + size
);
1050 if (size
& (u64
)(sdp
->sd_sb
.sb_bsize
- 1))
1051 error
= gfs2_block_truncate_page(ip
->i_inode
.i_mapping
);
1054 ip
->i_disksize
= size
;
1055 ip
->i_inode
.i_mtime
= ip
->i_inode
.i_ctime
= CURRENT_TIME
;
1056 ip
->i_diskflags
|= GFS2_DIF_TRUNC_IN_PROG
;
1057 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
1058 gfs2_dinode_out(ip
, dibh
->b_data
);
1065 gfs2_trans_end(sdp
);
1069 static int trunc_dealloc(struct gfs2_inode
*ip
, u64 size
)
1071 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1072 unsigned int height
= ip
->i_height
;
1080 lblock
= (size
- 1) >> sdp
->sd_sb
.sb_bsize_shift
;
1082 find_metapath(sdp
, lblock
, &mp
, ip
->i_height
);
1083 if (!gfs2_alloc_get(ip
))
1086 error
= gfs2_quota_hold(ip
, NO_QUOTA_CHANGE
, NO_QUOTA_CHANGE
);
1091 struct strip_mine sm
;
1092 sm
.sm_first
= !!size
;
1093 sm
.sm_height
= height
;
1095 error
= recursive_scan(ip
, NULL
, &mp
, 0, 0, 1, do_strip
, &sm
);
1100 gfs2_quota_unhold(ip
);
1107 static int trunc_end(struct gfs2_inode
*ip
)
1109 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1110 struct buffer_head
*dibh
;
1113 error
= gfs2_trans_begin(sdp
, RES_DINODE
, 0);
1117 down_write(&ip
->i_rw_mutex
);
1119 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
1123 if (!ip
->i_disksize
) {
1125 ip
->i_goal
= ip
->i_no_addr
;
1126 gfs2_buffer_clear_tail(dibh
, sizeof(struct gfs2_dinode
));
1128 ip
->i_inode
.i_mtime
= ip
->i_inode
.i_ctime
= CURRENT_TIME
;
1129 ip
->i_diskflags
&= ~GFS2_DIF_TRUNC_IN_PROG
;
1131 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
1132 gfs2_dinode_out(ip
, dibh
->b_data
);
1136 up_write(&ip
->i_rw_mutex
);
1137 gfs2_trans_end(sdp
);
1142 * do_shrink - make a file smaller
1144 * @size: the size to make the file
1145 * @truncator: function to truncate the last partial block
1147 * Called with an exclusive lock on @ip.
1152 static int do_shrink(struct gfs2_inode
*ip
, u64 size
)
1156 error
= trunc_start(ip
, size
);
1162 error
= trunc_dealloc(ip
, size
);
1164 error
= trunc_end(ip
);
1169 static int do_touch(struct gfs2_inode
*ip
, u64 size
)
1171 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1172 struct buffer_head
*dibh
;
1175 error
= gfs2_trans_begin(sdp
, RES_DINODE
, 0);
1179 down_write(&ip
->i_rw_mutex
);
1181 error
= gfs2_meta_inode_buffer(ip
, &dibh
);
1185 ip
->i_inode
.i_mtime
= ip
->i_inode
.i_ctime
= CURRENT_TIME
;
1186 gfs2_trans_add_bh(ip
->i_gl
, dibh
, 1);
1187 gfs2_dinode_out(ip
, dibh
->b_data
);
1191 up_write(&ip
->i_rw_mutex
);
1192 gfs2_trans_end(sdp
);
1197 * gfs2_truncatei - make a file a given size
1199 * @size: the size to make the file
1200 * @truncator: function to truncate the last partial block
1202 * The file size can grow, shrink, or stay the same size.
1207 int gfs2_truncatei(struct gfs2_inode
*ip
, u64 size
)
1211 if (gfs2_assert_warn(GFS2_SB(&ip
->i_inode
), S_ISREG(ip
->i_inode
.i_mode
)))
1214 if (size
> ip
->i_disksize
)
1215 error
= do_grow(ip
, size
);
1216 else if (size
< ip
->i_disksize
)
1217 error
= do_shrink(ip
, size
);
1219 /* update time stamps */
1220 error
= do_touch(ip
, size
);
1225 int gfs2_truncatei_resume(struct gfs2_inode
*ip
)
1228 error
= trunc_dealloc(ip
, ip
->i_disksize
);
1230 error
= trunc_end(ip
);
1234 int gfs2_file_dealloc(struct gfs2_inode
*ip
)
1236 return trunc_dealloc(ip
, 0);
1240 * gfs2_write_alloc_required - figure out if a write will require an allocation
1241 * @ip: the file being written to
1242 * @offset: the offset to write to
1243 * @len: the number of bytes being written
1244 * @alloc_required: set to 1 if an alloc is required, 0 otherwise
1249 int gfs2_write_alloc_required(struct gfs2_inode
*ip
, u64 offset
,
1250 unsigned int len
, int *alloc_required
)
1252 struct gfs2_sbd
*sdp
= GFS2_SB(&ip
->i_inode
);
1253 struct buffer_head bh
;
1255 u64 lblock
, lblock_stop
, size
;
1258 *alloc_required
= 0;
1263 if (gfs2_is_stuffed(ip
)) {
1265 sdp
->sd_sb
.sb_bsize
- sizeof(struct gfs2_dinode
))
1266 *alloc_required
= 1;
1270 *alloc_required
= 1;
1271 shift
= sdp
->sd_sb
.sb_bsize_shift
;
1272 BUG_ON(gfs2_is_dir(ip
));
1273 end_of_file
= (ip
->i_disksize
+ sdp
->sd_sb
.sb_bsize
- 1) >> shift
;
1274 lblock
= offset
>> shift
;
1275 lblock_stop
= (offset
+ len
+ sdp
->sd_sb
.sb_bsize
- 1) >> shift
;
1276 if (lblock_stop
> end_of_file
)
1279 size
= (lblock_stop
- lblock
) << shift
;
1283 gfs2_block_map(&ip
->i_inode
, lblock
, &bh
, 0);
1284 if (!buffer_mapped(&bh
))
1287 lblock
+= (bh
.b_size
>> ip
->i_inode
.i_blkbits
);
1290 *alloc_required
= 0;