blob: e65493a8ac002ad91a68433bf76dbe2243ff08e1 [file] [log] [blame]
David Teiglandb3b94fa2006-01-16 16:50:04 +00001/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
Steven Whitehouse3a8a9a12006-05-18 15:09:15 -04003 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
David Teiglandb3b94fa2006-01-16 16:50:04 +00004 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
Steven Whitehousee9fc2aa2006-09-01 11:05:15 -04007 * of the GNU General Public License version 2.
David Teiglandb3b94fa2006-01-16 16:50:04 +00008 */
9
David Teiglandb3b94fa2006-01-16 16:50:04 +000010#include <linux/spinlock.h>
11#include <linux/completion.h>
12#include <linux/buffer_head.h>
Steven Whitehouse5c676f62006-02-27 17:23:27 -050013#include <linux/gfs2_ondisk.h>
Steven Whitehouse71b86f52006-03-28 14:14:04 -050014#include <linux/crc32.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000015
16#include "gfs2.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050017#include "incore.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000018#include "bmap.h"
19#include "glock.h"
20#include "inode.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000021#include "meta_io.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000022#include "quota.h"
23#include "rgrp.h"
Bob Peterson4c16c362011-02-23 16:11:33 -050024#include "super.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000025#include "trans.h"
Steven Whitehouse18ec7d52006-02-08 11:50:51 +000026#include "dir.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050027#include "util.h"
Steven Whitehouse63997772009-06-12 08:49:20 +010028#include "trace_gfs2.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000029
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
32 * keep it small.
33 */
34struct metapath {
Steven Whitehousedbac6712008-01-29 09:12:55 +000035 struct buffer_head *mp_bh[GFS2_MAX_META_HEIGHT];
David Teiglandb3b94fa2006-01-16 16:50:04 +000036 __u16 mp_list[GFS2_MAX_META_HEIGHT];
37};
38
39typedef int (*block_call_t) (struct gfs2_inode *ip, struct buffer_head *dibh,
Al Virob44b84d2006-10-14 10:46:30 -040040 struct buffer_head *bh, __be64 *top,
41 __be64 *bottom, unsigned int height,
David Teiglandb3b94fa2006-01-16 16:50:04 +000042 void *data);
43
44struct strip_mine {
45 int sm_first;
46 unsigned int sm_height;
47};
48
49/**
Steven Whitehousef25ef0c2006-07-26 10:51:20 -040050 * gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page
51 * @ip: the inode
52 * @dibh: the dinode buffer
53 * @block: the block number that was allocated
Steven Whitehouseff8f33c2010-08-11 09:37:53 +010054 * @page: The (optional) page. This is looked up if @page is NULL
Steven Whitehousef25ef0c2006-07-26 10:51:20 -040055 *
56 * Returns: errno
57 */
58
59static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh,
Steven Whitehousecd915492006-09-04 12:49:07 -040060 u64 block, struct page *page)
Steven Whitehousef25ef0c2006-07-26 10:51:20 -040061{
Steven Whitehousef25ef0c2006-07-26 10:51:20 -040062 struct inode *inode = &ip->i_inode;
63 struct buffer_head *bh;
64 int release = 0;
65
66 if (!page || page->index) {
67 page = grab_cache_page(inode->i_mapping, 0);
68 if (!page)
69 return -ENOMEM;
70 release = 1;
71 }
72
73 if (!PageUptodate(page)) {
74 void *kaddr = kmap(page);
Steven Whitehouse602c89d2010-03-25 14:32:43 +000075 u64 dsize = i_size_read(inode);
76
77 if (dsize > (dibh->b_size - sizeof(struct gfs2_dinode)))
78 dsize = dibh->b_size - sizeof(struct gfs2_dinode);
Steven Whitehousef25ef0c2006-07-26 10:51:20 -040079
Steven Whitehouse602c89d2010-03-25 14:32:43 +000080 memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
81 memset(kaddr + dsize, 0, PAGE_CACHE_SIZE - dsize);
Steven Whitehousef25ef0c2006-07-26 10:51:20 -040082 kunmap(page);
83
84 SetPageUptodate(page);
85 }
86
87 if (!page_has_buffers(page))
88 create_empty_buffers(page, 1 << inode->i_blkbits,
89 (1 << BH_Uptodate));
90
91 bh = page_buffers(page);
92
93 if (!buffer_mapped(bh))
94 map_bh(bh, inode->i_sb, block);
95
96 set_buffer_uptodate(bh);
Steven Whitehouseeaf96522007-08-27 09:49:37 +010097 if (!gfs2_is_jdata(ip))
98 mark_buffer_dirty(bh);
Steven Whitehousebf36a712007-10-17 08:35:19 +010099 if (!gfs2_is_writeback(ip))
Bob Peterson84754872007-09-02 10:55:29 +0100100 gfs2_trans_add_bh(ip->i_gl, bh, 0);
Steven Whitehousef25ef0c2006-07-26 10:51:20 -0400101
102 if (release) {
103 unlock_page(page);
104 page_cache_release(page);
105 }
106
107 return 0;
108}
109
110/**
David Teiglandb3b94fa2006-01-16 16:50:04 +0000111 * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big
112 * @ip: The GFS2 inode to unstuff
Steven Whitehouseff8f33c2010-08-11 09:37:53 +0100113 * @page: The (optional) page. This is looked up if the @page is NULL
David Teiglandb3b94fa2006-01-16 16:50:04 +0000114 *
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.
117 *
118 * Returns: errno
119 */
120
Steven Whitehousef25ef0c2006-07-26 10:51:20 -0400121int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000122{
123 struct buffer_head *bh, *dibh;
Steven Whitehouse48516ce2006-10-02 12:39:19 -0400124 struct gfs2_dinode *di;
Steven Whitehousecd915492006-09-04 12:49:07 -0400125 u64 block = 0;
Steven Whitehouse18ec7d52006-02-08 11:50:51 +0000126 int isdir = gfs2_is_dir(ip);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000127 int error;
128
129 down_write(&ip->i_rw_mutex);
130
131 error = gfs2_meta_inode_buffer(ip, &dibh);
132 if (error)
133 goto out;
Steven Whitehouse907b9bc2006-09-25 09:26:04 -0400134
Steven Whitehousea2e0f792010-08-11 09:53:11 +0100135 if (i_size_read(&ip->i_inode)) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000136 /* Get a free block, fill it with the stuffed data,
137 and write it out to disk */
138
Steven Whitehouseb45e41d2008-02-06 10:11:15 +0000139 unsigned int n = 1;
Steven Whitehouse09010972009-05-20 10:48:47 +0100140 error = gfs2_alloc_block(ip, &block, &n);
141 if (error)
142 goto out_brelse;
Steven Whitehouse18ec7d52006-02-08 11:50:51 +0000143 if (isdir) {
Steven Whitehouse5731be52008-02-01 13:16:55 +0000144 gfs2_trans_add_unrevoke(GFS2_SB(&ip->i_inode), block, 1);
Steven Whitehouse61e085a2006-04-24 10:07:13 -0400145 error = gfs2_dir_get_new_buffer(ip, block, &bh);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000146 if (error)
147 goto out_brelse;
Steven Whitehouse48516ce2006-10-02 12:39:19 -0400148 gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_meta_header),
David Teiglandb3b94fa2006-01-16 16:50:04 +0000149 dibh, sizeof(struct gfs2_dinode));
150 brelse(bh);
151 } else {
Steven Whitehousef25ef0c2006-07-26 10:51:20 -0400152 error = gfs2_unstuffer_page(ip, dibh, block, page);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000153 if (error)
154 goto out_brelse;
155 }
156 }
157
158 /* Set up the pointer to the new block */
159
Steven Whitehoused4e9c4c2006-01-18 11:19:28 +0000160 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
Steven Whitehouse48516ce2006-10-02 12:39:19 -0400161 di = (struct gfs2_dinode *)dibh->b_data;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000162 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
163
Steven Whitehousea2e0f792010-08-11 09:53:11 +0100164 if (i_size_read(&ip->i_inode)) {
Steven Whitehouse48516ce2006-10-02 12:39:19 -0400165 *(__be64 *)(di + 1) = cpu_to_be64(block);
Steven Whitehouse77658aa2008-02-12 14:17:27 +0000166 gfs2_add_inode_blocks(&ip->i_inode, 1);
167 di->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000168 }
169
Steven Whitehouseecc30c72008-01-28 10:37:35 +0000170 ip->i_height = 1;
Steven Whitehouse48516ce2006-10-02 12:39:19 -0400171 di->di_height = cpu_to_be16(1);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000172
Steven Whitehousea91ea692006-09-04 12:04:26 -0400173out_brelse:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000174 brelse(dibh);
Steven Whitehousea91ea692006-09-04 12:04:26 -0400175out:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000176 up_write(&ip->i_rw_mutex);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000177 return error;
178}
179
David Teiglandb3b94fa2006-01-16 16:50:04 +0000180
181/**
182 * find_metapath - Find path through the metadata tree
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000183 * @sdp: The superblock
David Teiglandb3b94fa2006-01-16 16:50:04 +0000184 * @mp: The metapath to return the result in
185 * @block: The disk block to look up
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000186 * @height: The pre-calculated height of the metadata tree
David Teiglandb3b94fa2006-01-16 16:50:04 +0000187 *
188 * This routine returns a struct metapath structure that defines a path
189 * through the metadata of inode "ip" to get to block "block".
190 *
191 * Example:
192 * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a
193 * filesystem with a blocksize of 4096.
194 *
195 * find_metapath() would return a struct metapath structure set to:
196 * mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48,
197 * and mp_list[2] = 165.
198 *
199 * That means that in order to get to the block containing the byte at
200 * offset 101342453, we would load the indirect block pointed to by pointer
201 * 0 in the dinode. We would then load the indirect block pointed to by
202 * pointer 48 in that indirect block. We would then load the data block
203 * pointed to by pointer 165 in that indirect block.
204 *
205 * ----------------------------------------
206 * | Dinode | |
207 * | | 4|
208 * | |0 1 2 3 4 5 9|
209 * | | 6|
210 * ----------------------------------------
211 * |
212 * |
213 * V
214 * ----------------------------------------
215 * | Indirect Block |
216 * | 5|
217 * | 4 4 4 4 4 5 5 1|
218 * |0 5 6 7 8 9 0 1 2|
219 * ----------------------------------------
220 * |
221 * |
222 * V
223 * ----------------------------------------
224 * | Indirect Block |
225 * | 1 1 1 1 1 5|
226 * | 6 6 6 6 6 1|
227 * |0 3 4 5 6 7 2|
228 * ----------------------------------------
229 * |
230 * |
231 * V
232 * ----------------------------------------
233 * | Data block containing offset |
234 * | 101342453 |
235 * | |
236 * | |
237 * ----------------------------------------
238 *
239 */
240
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000241static void find_metapath(const struct gfs2_sbd *sdp, u64 block,
242 struct metapath *mp, unsigned int height)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000243{
David Teiglandb3b94fa2006-01-16 16:50:04 +0000244 unsigned int i;
245
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000246 for (i = height; i--;)
Bob Peterson7eabb772008-01-28 11:24:35 -0600247 mp->mp_list[i] = do_div(block, sdp->sd_inptrs);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000248
249}
250
Benjamin Marzinski5af4e7a2008-06-24 12:53:38 -0500251static inline unsigned int metapath_branch_start(const struct metapath *mp)
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000252{
Benjamin Marzinski5af4e7a2008-06-24 12:53:38 -0500253 if (mp->mp_list[0] == 0)
254 return 2;
255 return 1;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000256}
257
David Teiglandb3b94fa2006-01-16 16:50:04 +0000258/**
259 * metapointer - Return pointer to start of metadata in a buffer
David Teiglandb3b94fa2006-01-16 16:50:04 +0000260 * @height: The metadata height (0 = dinode)
261 * @mp: The metapath
262 *
263 * Return a pointer to the block number of the next height of the metadata
264 * tree given a buffer containing the pointer to the current height of the
265 * metadata tree.
266 */
267
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000268static inline __be64 *metapointer(unsigned int height, const struct metapath *mp)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000269{
Steven Whitehousedbac6712008-01-29 09:12:55 +0000270 struct buffer_head *bh = mp->mp_bh[height];
David Teiglandb3b94fa2006-01-16 16:50:04 +0000271 unsigned int head_size = (height > 0) ?
272 sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode);
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000273 return ((__be64 *)(bh->b_data + head_size)) + mp->mp_list[height];
David Teiglandb3b94fa2006-01-16 16:50:04 +0000274}
275
276/**
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000277 * lookup_metapath - Walk the metadata tree to a specific point
278 * @ip: The inode
David Teiglandb3b94fa2006-01-16 16:50:04 +0000279 * @mp: The metapath
David Teiglandb3b94fa2006-01-16 16:50:04 +0000280 *
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000281 * Assumes that the inode's buffer has already been looked up and
282 * hooked onto mp->mp_bh[0] and that the metapath has been initialised
283 * by find_metapath().
David Teiglandb3b94fa2006-01-16 16:50:04 +0000284 *
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000285 * If this function encounters part of the tree which has not been
286 * allocated, it returns the current height of the tree at the point
287 * at which it found the unallocated block. Blocks which are found are
288 * added to the mp->mp_bh[] list.
289 *
290 * Returns: error or height of metadata tree
David Teiglandb3b94fa2006-01-16 16:50:04 +0000291 */
292
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000293static int lookup_metapath(struct gfs2_inode *ip, struct metapath *mp)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000294{
Steven Whitehouse11707ea2008-01-28 15:10:29 +0000295 unsigned int end_of_metadata = ip->i_height - 1;
296 unsigned int x;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000297 __be64 *ptr;
298 u64 dblock;
Steven Whitehousee23159d2008-02-12 14:48:39 +0000299 int ret;
Steven Whitehouse11707ea2008-01-28 15:10:29 +0000300
301 for (x = 0; x < end_of_metadata; x++) {
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000302 ptr = metapointer(x, mp);
303 dblock = be64_to_cpu(*ptr);
304 if (!dblock)
305 return x + 1;
Steven Whitehouse11707ea2008-01-28 15:10:29 +0000306
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000307 ret = gfs2_meta_indirect_buffer(ip, x+1, dblock, 0, &mp->mp_bh[x+1]);
Steven Whitehouse11707ea2008-01-28 15:10:29 +0000308 if (ret)
309 return ret;
310 }
311
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000312 return ip->i_height;
Steven Whitehousedbac6712008-01-29 09:12:55 +0000313}
314
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000315static inline void release_metapath(struct metapath *mp)
Steven Whitehousedbac6712008-01-29 09:12:55 +0000316{
317 int i;
318
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000319 for (i = 0; i < GFS2_MAX_META_HEIGHT; i++) {
320 if (mp->mp_bh[i] == NULL)
321 break;
322 brelse(mp->mp_bh[i]);
323 }
Steven Whitehouse11707ea2008-01-28 15:10:29 +0000324}
325
Steven Whitehouse30cbf182008-02-08 13:18:11 +0000326/**
327 * gfs2_extent_length - Returns length of an extent of blocks
328 * @start: Start of the buffer
329 * @len: Length of the buffer in bytes
330 * @ptr: Current position in the buffer
331 * @limit: Max extent length to return (0 = unlimited)
332 * @eob: Set to 1 if we hit "end of block"
333 *
334 * If the first block is zero (unallocated) it will return the number of
335 * unallocated blocks in the extent, otherwise it will return the number
336 * of contiguous blocks in the extent.
337 *
338 * Returns: The length of the extent (minimum of one block)
339 */
340
341static inline unsigned int gfs2_extent_length(void *start, unsigned int len, __be64 *ptr, unsigned limit, int *eob)
342{
343 const __be64 *end = (start + len);
344 const __be64 *first = ptr;
345 u64 d = be64_to_cpu(*ptr);
346
347 *eob = 0;
348 do {
349 ptr++;
350 if (ptr >= end)
351 break;
352 if (limit && --limit == 0)
353 break;
354 if (d)
355 d++;
356 } while(be64_to_cpu(*ptr) == d);
357 if (ptr >= end)
358 *eob = 1;
359 return (ptr - first);
360}
361
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000362static inline void bmap_lock(struct gfs2_inode *ip, int create)
Steven Whitehousefd88de562006-05-05 16:59:11 -0400363{
Steven Whitehousefd88de562006-05-05 16:59:11 -0400364 if (create)
365 down_write(&ip->i_rw_mutex);
366 else
367 down_read(&ip->i_rw_mutex);
368}
369
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000370static inline void bmap_unlock(struct gfs2_inode *ip, int create)
Steven Whitehousefd88de562006-05-05 16:59:11 -0400371{
David Teiglandb3b94fa2006-01-16 16:50:04 +0000372 if (create)
373 up_write(&ip->i_rw_mutex);
374 else
375 up_read(&ip->i_rw_mutex);
Steven Whitehousefd88de562006-05-05 16:59:11 -0400376}
David Teiglandb3b94fa2006-01-16 16:50:04 +0000377
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000378static inline __be64 *gfs2_indirect_init(struct metapath *mp,
379 struct gfs2_glock *gl, unsigned int i,
380 unsigned offset, u64 bn)
381{
382 __be64 *ptr = (__be64 *)(mp->mp_bh[i - 1]->b_data +
383 ((i > 1) ? sizeof(struct gfs2_meta_header) :
384 sizeof(struct gfs2_dinode)));
385 BUG_ON(i < 1);
386 BUG_ON(mp->mp_bh[i] != NULL);
387 mp->mp_bh[i] = gfs2_meta_new(gl, bn);
388 gfs2_trans_add_bh(gl, mp->mp_bh[i], 1);
389 gfs2_metatype_set(mp->mp_bh[i], GFS2_METATYPE_IN, GFS2_FORMAT_IN);
390 gfs2_buffer_clear_tail(mp->mp_bh[i], sizeof(struct gfs2_meta_header));
391 ptr += offset;
392 *ptr = cpu_to_be64(bn);
393 return ptr;
394}
395
396enum alloc_state {
397 ALLOC_DATA = 0,
398 ALLOC_GROW_DEPTH = 1,
399 ALLOC_GROW_HEIGHT = 2,
400 /* ALLOC_UNSTUFF = 3, TBD and rather complicated */
401};
402
403/**
404 * gfs2_bmap_alloc - Build a metadata tree of the requested height
405 * @inode: The GFS2 inode
406 * @lblock: The logical starting block of the extent
407 * @bh_map: This is used to return the mapping details
408 * @mp: The metapath
409 * @sheight: The starting height (i.e. whats already mapped)
410 * @height: The height to build to
411 * @maxlen: The max number of data blocks to alloc
412 *
413 * In this routine we may have to alloc:
414 * i) Indirect blocks to grow the metadata tree height
415 * ii) Indirect blocks to fill in lower part of the metadata tree
416 * iii) Data blocks
417 *
418 * The function is in two parts. The first part works out the total
419 * number of blocks which we need. The second part does the actual
420 * allocation asking for an extent at a time (if enough contiguous free
421 * blocks are available, there will only be one request per bmap call)
422 * and uses the state machine to initialise the blocks in order.
423 *
424 * Returns: errno on error
425 */
426
427static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock,
428 struct buffer_head *bh_map, struct metapath *mp,
429 const unsigned int sheight,
430 const unsigned int height,
431 const unsigned int maxlen)
432{
433 struct gfs2_inode *ip = GFS2_I(inode);
434 struct gfs2_sbd *sdp = GFS2_SB(inode);
435 struct buffer_head *dibh = mp->mp_bh[0];
436 u64 bn, dblock = 0;
Benjamin Marzinski5af4e7a2008-06-24 12:53:38 -0500437 unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000438 unsigned dblks = 0;
439 unsigned ptrs_per_blk;
440 const unsigned end_of_metadata = height - 1;
441 int eob = 0;
442 enum alloc_state state;
443 __be64 *ptr;
444 __be64 zero_bn = 0;
445
446 BUG_ON(sheight < 1);
447 BUG_ON(dibh == NULL);
448
449 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
450
451 if (height == sheight) {
452 struct buffer_head *bh;
453 /* Bottom indirect block exists, find unalloced extent size */
454 ptr = metapointer(end_of_metadata, mp);
455 bh = mp->mp_bh[end_of_metadata];
456 dblks = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen,
457 &eob);
458 BUG_ON(dblks < 1);
459 state = ALLOC_DATA;
460 } else {
461 /* Need to allocate indirect blocks */
462 ptrs_per_blk = height > 1 ? sdp->sd_inptrs : sdp->sd_diptrs;
463 dblks = min(maxlen, ptrs_per_blk - mp->mp_list[end_of_metadata]);
464 if (height == ip->i_height) {
465 /* Writing into existing tree, extend tree down */
466 iblks = height - sheight;
467 state = ALLOC_GROW_DEPTH;
468 } else {
469 /* Building up tree height */
470 state = ALLOC_GROW_HEIGHT;
471 iblks = height - ip->i_height;
Benjamin Marzinski5af4e7a2008-06-24 12:53:38 -0500472 branch_start = metapath_branch_start(mp);
473 iblks += (height - branch_start);
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000474 }
475 }
476
477 /* start of the second part of the function (state machine) */
478
479 blks = dblks + iblks;
480 i = sheight;
481 do {
Steven Whitehouse09010972009-05-20 10:48:47 +0100482 int error;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000483 n = blks - alloced;
Steven Whitehouse09010972009-05-20 10:48:47 +0100484 error = gfs2_alloc_block(ip, &bn, &n);
485 if (error)
486 return error;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000487 alloced += n;
488 if (state != ALLOC_DATA || gfs2_is_jdata(ip))
489 gfs2_trans_add_unrevoke(sdp, bn, n);
490 switch (state) {
491 /* Growing height of tree */
492 case ALLOC_GROW_HEIGHT:
493 if (i == 1) {
494 ptr = (__be64 *)(dibh->b_data +
495 sizeof(struct gfs2_dinode));
496 zero_bn = *ptr;
497 }
498 for (; i - 1 < height - ip->i_height && n > 0; i++, n--)
499 gfs2_indirect_init(mp, ip->i_gl, i, 0, bn++);
500 if (i - 1 == height - ip->i_height) {
501 i--;
502 gfs2_buffer_copy_tail(mp->mp_bh[i],
503 sizeof(struct gfs2_meta_header),
504 dibh, sizeof(struct gfs2_dinode));
505 gfs2_buffer_clear_tail(dibh,
506 sizeof(struct gfs2_dinode) +
507 sizeof(__be64));
508 ptr = (__be64 *)(mp->mp_bh[i]->b_data +
509 sizeof(struct gfs2_meta_header));
510 *ptr = zero_bn;
511 state = ALLOC_GROW_DEPTH;
Benjamin Marzinski5af4e7a2008-06-24 12:53:38 -0500512 for(i = branch_start; i < height; i++) {
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000513 if (mp->mp_bh[i] == NULL)
514 break;
515 brelse(mp->mp_bh[i]);
516 mp->mp_bh[i] = NULL;
517 }
Benjamin Marzinski5af4e7a2008-06-24 12:53:38 -0500518 i = branch_start;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000519 }
520 if (n == 0)
521 break;
522 /* Branching from existing tree */
523 case ALLOC_GROW_DEPTH:
524 if (i > 1 && i < height)
525 gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[i-1], 1);
526 for (; i < height && n > 0; i++, n--)
527 gfs2_indirect_init(mp, ip->i_gl, i,
528 mp->mp_list[i-1], bn++);
529 if (i == height)
530 state = ALLOC_DATA;
531 if (n == 0)
532 break;
533 /* Tree complete, adding data blocks */
534 case ALLOC_DATA:
535 BUG_ON(n > dblks);
536 BUG_ON(mp->mp_bh[end_of_metadata] == NULL);
537 gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[end_of_metadata], 1);
538 dblks = n;
539 ptr = metapointer(end_of_metadata, mp);
540 dblock = bn;
541 while (n-- > 0)
542 *ptr++ = cpu_to_be64(bn++);
543 break;
544 }
Steven Whitehouse07ccb7b2010-02-12 10:10:55 +0000545 } while ((state != ALLOC_DATA) || !dblock);
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000546
547 ip->i_height = height;
548 gfs2_add_inode_blocks(&ip->i_inode, alloced);
549 gfs2_dinode_out(ip, mp->mp_bh[0]->b_data);
550 map_bh(bh_map, inode->i_sb, dblock);
551 bh_map->b_size = dblks << inode->i_blkbits;
552 set_buffer_new(bh_map);
553 return 0;
554}
555
Steven Whitehouse4cf1ed82006-11-15 15:21:06 -0500556/**
557 * gfs2_block_map - Map a block from an inode to a disk block
558 * @inode: The inode
559 * @lblock: The logical block number
560 * @bh_map: The bh to be mapped
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000561 * @create: True if its ok to alloc blocks to satify the request
Steven Whitehouse4cf1ed82006-11-15 15:21:06 -0500562 *
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000563 * Sets buffer_mapped() if successful, sets buffer_boundary() if a
564 * read of metadata will be required before the next block can be
565 * mapped. Sets buffer_new() if new blocks were allocated.
Steven Whitehouse4cf1ed82006-11-15 15:21:06 -0500566 *
567 * Returns: errno
568 */
569
Bob Petersone9e1ef22007-12-10 14:13:27 -0600570int gfs2_block_map(struct inode *inode, sector_t lblock,
571 struct buffer_head *bh_map, int create)
Steven Whitehousefd88de562006-05-05 16:59:11 -0400572{
Steven Whitehouse4cf1ed82006-11-15 15:21:06 -0500573 struct gfs2_inode *ip = GFS2_I(inode);
574 struct gfs2_sbd *sdp = GFS2_SB(inode);
Steven Whitehouseecc30c72008-01-28 10:37:35 +0000575 unsigned int bsize = sdp->sd_sb.sb_bsize;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000576 const unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
Steven Whitehouseecc30c72008-01-28 10:37:35 +0000577 const u64 *arr = sdp->sd_heightsize;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000578 __be64 *ptr;
579 u64 size;
580 struct metapath mp;
581 int ret;
582 int eob;
583 unsigned int len;
584 struct buffer_head *bh;
585 u8 height;
586
Steven Whitehouse4cf1ed82006-11-15 15:21:06 -0500587 BUG_ON(maxlen == 0);
588
Steven Whitehousedbac6712008-01-29 09:12:55 +0000589 memset(mp.mp_bh, 0, sizeof(mp.mp_bh));
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000590 bmap_lock(ip, create);
Steven Whitehouse4cf1ed82006-11-15 15:21:06 -0500591 clear_buffer_mapped(bh_map);
592 clear_buffer_new(bh_map);
593 clear_buffer_boundary(bh_map);
Steven Whitehouse63997772009-06-12 08:49:20 +0100594 trace_gfs2_bmap(ip, bh_map, lblock, create, 1);
Steven Whitehouseecc30c72008-01-28 10:37:35 +0000595 if (gfs2_is_dir(ip)) {
596 bsize = sdp->sd_jbsize;
597 arr = sdp->sd_jheightsize;
598 }
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000599
600 ret = gfs2_meta_inode_buffer(ip, &mp.mp_bh[0]);
601 if (ret)
602 goto out;
603
604 height = ip->i_height;
Steven Whitehouse4cf1ed82006-11-15 15:21:06 -0500605 size = (lblock + 1) * bsize;
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000606 while (size > arr[height])
607 height++;
608 find_metapath(sdp, lblock, &mp, height);
609 ret = 1;
610 if (height > ip->i_height || gfs2_is_stuffed(ip))
611 goto do_alloc;
612 ret = lookup_metapath(ip, &mp);
613 if (ret < 0)
614 goto out;
615 if (ret != ip->i_height)
616 goto do_alloc;
617 ptr = metapointer(ip->i_height - 1, &mp);
618 if (*ptr == 0)
619 goto do_alloc;
620 map_bh(bh_map, inode->i_sb, be64_to_cpu(*ptr));
621 bh = mp.mp_bh[ip->i_height - 1];
622 len = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen, &eob);
623 bh_map->b_size = (len << inode->i_blkbits);
624 if (eob)
625 set_buffer_boundary(bh_map);
626 ret = 0;
627out:
Steven Whitehousedbac6712008-01-29 09:12:55 +0000628 release_metapath(&mp);
Steven Whitehouse63997772009-06-12 08:49:20 +0100629 trace_gfs2_bmap(ip, bh_map, lblock, create, ret);
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000630 bmap_unlock(ip, create);
631 return ret;
632
633do_alloc:
634 /* All allocations are done here, firstly check create flag */
635 if (!create) {
636 BUG_ON(gfs2_is_stuffed(ip));
637 ret = 0;
638 goto out;
639 }
640
641 /* At this point ret is the tree depth of already allocated blocks */
642 ret = gfs2_bmap_alloc(inode, lblock, bh_map, &mp, ret, height, maxlen);
643 goto out;
Steven Whitehousefd88de562006-05-05 16:59:11 -0400644}
645
Steven Whitehouse941e6d72008-01-28 08:47:38 +0000646/*
647 * Deprecated: do not use in new code
648 */
Steven Whitehousefd88de562006-05-05 16:59:11 -0400649int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
650{
Steven Whitehouse23591252006-10-13 17:25:45 -0400651 struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 };
Steven Whitehouse7a6bbac2006-09-18 17:18:23 -0400652 int ret;
Steven Whitehousefd88de562006-05-05 16:59:11 -0400653 int create = *new;
654
655 BUG_ON(!extlen);
656 BUG_ON(!dblock);
657 BUG_ON(!new);
658
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +0000659 bh.b_size = 1 << (inode->i_blkbits + (create ? 0 : 5));
Bob Petersone9e1ef22007-12-10 14:13:27 -0600660 ret = gfs2_block_map(inode, lblock, &bh, create);
Steven Whitehouse7a6bbac2006-09-18 17:18:23 -0400661 *extlen = bh.b_size >> inode->i_blkbits;
662 *dblock = bh.b_blocknr;
663 if (buffer_new(&bh))
664 *new = 1;
665 else
666 *new = 0;
667 return ret;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000668}
669
670/**
671 * recursive_scan - recursively scan through the end of a file
672 * @ip: the inode
673 * @dibh: the dinode buffer
674 * @mp: the path through the metadata to the point to start
675 * @height: the height the recursion is at
676 * @block: the indirect block to look at
677 * @first: 1 if this is the first block
678 * @bc: the call to make for each piece of metadata
679 * @data: data opaque to this function to pass to @bc
680 *
681 * When this is first called @height and @block should be zero and
682 * @first should be 1.
683 *
684 * Returns: errno
685 */
686
687static int recursive_scan(struct gfs2_inode *ip, struct buffer_head *dibh,
688 struct metapath *mp, unsigned int height,
Steven Whitehousecd915492006-09-04 12:49:07 -0400689 u64 block, int first, block_call_t bc,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000690 void *data)
691{
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400692 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000693 struct buffer_head *bh = NULL;
Al Virob44b84d2006-10-14 10:46:30 -0400694 __be64 *top, *bottom;
Steven Whitehousecd915492006-09-04 12:49:07 -0400695 u64 bn;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000696 int error;
697 int mh_size = sizeof(struct gfs2_meta_header);
698
699 if (!height) {
700 error = gfs2_meta_inode_buffer(ip, &bh);
701 if (error)
702 return error;
703 dibh = bh;
704
Al Virob44b84d2006-10-14 10:46:30 -0400705 top = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + mp->mp_list[0];
706 bottom = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + sdp->sd_diptrs;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000707 } else {
708 error = gfs2_meta_indirect_buffer(ip, height, block, 0, &bh);
709 if (error)
710 return error;
711
Al Virob44b84d2006-10-14 10:46:30 -0400712 top = (__be64 *)(bh->b_data + mh_size) +
Jan Engelhardtc53921242006-09-05 14:30:40 +0200713 (first ? mp->mp_list[height] : 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000714
Al Virob44b84d2006-10-14 10:46:30 -0400715 bottom = (__be64 *)(bh->b_data + mh_size) + sdp->sd_inptrs;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000716 }
717
718 error = bc(ip, dibh, bh, top, bottom, height, data);
719 if (error)
720 goto out;
721
Steven Whitehouseecc30c72008-01-28 10:37:35 +0000722 if (height < ip->i_height - 1)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000723 for (; top < bottom; top++, first = 0) {
724 if (!*top)
725 continue;
726
727 bn = be64_to_cpu(*top);
728
729 error = recursive_scan(ip, dibh, mp, height + 1, bn,
730 first, bc, data);
731 if (error)
732 break;
733 }
734
Steven Whitehousea91ea692006-09-04 12:04:26 -0400735out:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000736 brelse(bh);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000737 return error;
738}
739
740/**
741 * do_strip - Look for a layer a particular layer of the file and strip it off
742 * @ip: the inode
743 * @dibh: the dinode buffer
744 * @bh: A buffer of pointers
745 * @top: The first pointer in the buffer
746 * @bottom: One more than the last pointer
747 * @height: the height this buffer is at
748 * @data: a pointer to a struct strip_mine
749 *
750 * Returns: errno
751 */
752
753static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh,
Al Virob44b84d2006-10-14 10:46:30 -0400754 struct buffer_head *bh, __be64 *top, __be64 *bottom,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000755 unsigned int height, void *data)
756{
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400757 struct strip_mine *sm = data;
758 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000759 struct gfs2_rgrp_list rlist;
Steven Whitehousecd915492006-09-04 12:49:07 -0400760 u64 bn, bstart;
Bob Peterson4c16c362011-02-23 16:11:33 -0500761 u32 blen, btotal;
Al Virob44b84d2006-10-14 10:46:30 -0400762 __be64 *p;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000763 unsigned int rg_blocks = 0;
764 int metadata;
765 unsigned int revokes = 0;
766 int x;
Steven Whitehousee06dfc42010-11-30 15:46:02 +0000767 int error = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000768
769 if (!*top)
770 sm->sm_first = 0;
771
772 if (height != sm->sm_height)
773 return 0;
774
775 if (sm->sm_first) {
776 top++;
777 sm->sm_first = 0;
778 }
779
Steven Whitehouseecc30c72008-01-28 10:37:35 +0000780 metadata = (height != ip->i_height - 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000781 if (metadata)
782 revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs;
Steven Whitehouse6d3117b2011-05-21 14:05:58 +0100783 else if (ip->i_depth)
784 revokes = sdp->sd_inptrs;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000785
Benjamin Marzinski086d8332010-11-23 23:52:55 -0600786 if (ip != GFS2_I(sdp->sd_rindex))
787 error = gfs2_rindex_hold(sdp, &ip->i_alloc->al_ri_gh);
788 else if (!sdp->sd_rgrps)
789 error = gfs2_ri_update(ip);
790
David Teiglandb3b94fa2006-01-16 16:50:04 +0000791 if (error)
792 return error;
793
794 memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
795 bstart = 0;
796 blen = 0;
797
798 for (p = top; p < bottom; p++) {
799 if (!*p)
800 continue;
801
802 bn = be64_to_cpu(*p);
803
804 if (bstart + blen == bn)
805 blen++;
806 else {
807 if (bstart)
808 gfs2_rlist_add(sdp, &rlist, bstart);
809
810 bstart = bn;
811 blen = 1;
812 }
813 }
814
815 if (bstart)
816 gfs2_rlist_add(sdp, &rlist, bstart);
817 else
818 goto out; /* Nothing to do */
819
Bob Petersonfe6c9912008-01-28 11:13:02 -0600820 gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000821
822 for (x = 0; x < rlist.rl_rgrps; x++) {
823 struct gfs2_rgrpd *rgd;
Steven Whitehouse5c676f62006-02-27 17:23:27 -0500824 rgd = rlist.rl_ghs[x].gh_gl->gl_object;
Steven Whitehousebb8d8a62007-06-01 14:11:58 +0100825 rg_blocks += rgd->rd_length;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000826 }
827
828 error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs);
829 if (error)
830 goto out_rlist;
831
832 error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE +
833 RES_INDIRECT + RES_STATFS + RES_QUOTA,
834 revokes);
835 if (error)
836 goto out_rg_gunlock;
837
838 down_write(&ip->i_rw_mutex);
839
Steven Whitehoused4e9c4c2006-01-18 11:19:28 +0000840 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
841 gfs2_trans_add_bh(ip->i_gl, bh, 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000842
843 bstart = 0;
844 blen = 0;
Bob Peterson4c16c362011-02-23 16:11:33 -0500845 btotal = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000846
847 for (p = top; p < bottom; p++) {
848 if (!*p)
849 continue;
850
851 bn = be64_to_cpu(*p);
852
853 if (bstart + blen == bn)
854 blen++;
855 else {
856 if (bstart) {
857 if (metadata)
Bob Peterson4c16c362011-02-23 16:11:33 -0500858 __gfs2_free_meta(ip, bstart, blen);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000859 else
Bob Peterson4c16c362011-02-23 16:11:33 -0500860 __gfs2_free_data(ip, bstart, blen);
861
862 btotal += blen;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000863 }
864
865 bstart = bn;
866 blen = 1;
867 }
868
869 *p = 0;
Steven Whitehouse77658aa2008-02-12 14:17:27 +0000870 gfs2_add_inode_blocks(&ip->i_inode, -1);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000871 }
872 if (bstart) {
873 if (metadata)
Bob Peterson4c16c362011-02-23 16:11:33 -0500874 __gfs2_free_meta(ip, bstart, blen);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000875 else
Bob Peterson4c16c362011-02-23 16:11:33 -0500876 __gfs2_free_data(ip, bstart, blen);
877
878 btotal += blen;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000879 }
880
Bob Peterson4c16c362011-02-23 16:11:33 -0500881 gfs2_statfs_change(sdp, 0, +btotal, 0);
882 gfs2_quota_change(ip, -(s64)btotal, ip->i_inode.i_uid,
883 ip->i_inode.i_gid);
884
Steven Whitehouse4bd91ba2007-06-05 09:39:18 +0100885 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000886
Steven Whitehouse539e5d62006-10-31 15:07:05 -0500887 gfs2_dinode_out(ip, dibh->b_data);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000888
889 up_write(&ip->i_rw_mutex);
890
891 gfs2_trans_end(sdp);
892
Steven Whitehousea91ea692006-09-04 12:04:26 -0400893out_rg_gunlock:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000894 gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs);
Steven Whitehousea91ea692006-09-04 12:04:26 -0400895out_rlist:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000896 gfs2_rlist_free(&rlist);
Steven Whitehousea91ea692006-09-04 12:04:26 -0400897out:
Benjamin Marzinski086d8332010-11-23 23:52:55 -0600898 if (ip != GFS2_I(sdp->sd_rindex))
899 gfs2_glock_dq_uninit(&ip->i_alloc->al_ri_gh);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000900 return error;
901}
902
903/**
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400904 * gfs2_block_truncate_page - Deal with zeroing out data for truncate
905 *
906 * This is partly borrowed from ext3.
907 */
Steven Whitehouseff8f33c2010-08-11 09:37:53 +0100908static int gfs2_block_truncate_page(struct address_space *mapping, loff_t from)
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400909{
910 struct inode *inode = mapping->host;
911 struct gfs2_inode *ip = GFS2_I(inode);
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400912 unsigned long index = from >> PAGE_CACHE_SHIFT;
913 unsigned offset = from & (PAGE_CACHE_SIZE-1);
914 unsigned blocksize, iblock, length, pos;
915 struct buffer_head *bh;
916 struct page *page;
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400917 int err;
918
919 page = grab_cache_page(mapping, index);
920 if (!page)
921 return 0;
922
923 blocksize = inode->i_sb->s_blocksize;
924 length = blocksize - (offset & (blocksize - 1));
925 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
926
927 if (!page_has_buffers(page))
928 create_empty_buffers(page, blocksize, 0);
929
930 /* Find the buffer that contains "offset" */
931 bh = page_buffers(page);
932 pos = blocksize;
933 while (offset >= pos) {
934 bh = bh->b_this_page;
935 iblock++;
936 pos += blocksize;
937 }
938
939 err = 0;
940
941 if (!buffer_mapped(bh)) {
Bob Petersone9e1ef22007-12-10 14:13:27 -0600942 gfs2_block_map(inode, iblock, bh, 0);
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400943 /* unmapped? It's a hole - nothing to do */
944 if (!buffer_mapped(bh))
945 goto unlock;
946 }
947
948 /* Ok, it's mapped. Make sure it's up-to-date */
949 if (PageUptodate(page))
950 set_buffer_uptodate(bh);
951
952 if (!buffer_uptodate(bh)) {
953 err = -EIO;
954 ll_rw_block(READ, 1, &bh);
955 wait_on_buffer(bh);
956 /* Uhhuh. Read error. Complain and punt. */
957 if (!buffer_uptodate(bh))
958 goto unlock;
S. Wendy Cheng1875f2f2007-06-25 21:14:31 -0400959 err = 0;
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400960 }
961
Steven Whitehousebf36a712007-10-17 08:35:19 +0100962 if (!gfs2_is_writeback(ip))
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400963 gfs2_trans_add_bh(ip->i_gl, bh, 0);
964
Christoph Lametereebd2aa2008-02-04 22:28:29 -0800965 zero_user(page, offset, length);
Steven Whitehouse40bc9a22009-06-10 09:09:40 +0100966 mark_buffer_dirty(bh);
Steven Whitehouseba7f7292006-07-26 11:27:10 -0400967unlock:
968 unlock_page(page);
969 page_cache_release(page);
970 return err;
971}
972
Steven Whitehouseff8f33c2010-08-11 09:37:53 +0100973static int trunc_start(struct inode *inode, u64 oldsize, u64 newsize)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000974{
Steven Whitehouseff8f33c2010-08-11 09:37:53 +0100975 struct gfs2_inode *ip = GFS2_I(inode);
976 struct gfs2_sbd *sdp = GFS2_SB(inode);
977 struct address_space *mapping = inode->i_mapping;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000978 struct buffer_head *dibh;
979 int journaled = gfs2_is_jdata(ip);
980 int error;
981
982 error = gfs2_trans_begin(sdp,
Jan Engelhardtc53921242006-09-05 14:30:40 +0200983 RES_DINODE + (journaled ? RES_JDATA : 0), 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000984 if (error)
985 return error;
986
987 error = gfs2_meta_inode_buffer(ip, &dibh);
988 if (error)
989 goto out;
990
Steven Whitehouseff8f33c2010-08-11 09:37:53 +0100991 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000992
Steven Whitehouseff8f33c2010-08-11 09:37:53 +0100993 if (gfs2_is_stuffed(ip)) {
994 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + newsize);
995 } else {
996 if (newsize & (u64)(sdp->sd_sb.sb_bsize - 1)) {
997 error = gfs2_block_truncate_page(mapping, newsize);
998 if (error)
999 goto out_brelse;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001000 }
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001001 ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001002 }
1003
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001004 i_size_write(inode, newsize);
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001005 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
1006 gfs2_dinode_out(ip, dibh->b_data);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001007
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001008 truncate_pagecache(inode, oldsize, newsize);
1009out_brelse:
1010 brelse(dibh);
Steven Whitehousea91ea692006-09-04 12:04:26 -04001011out:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001012 gfs2_trans_end(sdp);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001013 return error;
1014}
1015
Steven Whitehousecd915492006-09-04 12:49:07 -04001016static int trunc_dealloc(struct gfs2_inode *ip, u64 size)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001017{
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +00001018 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
Steven Whitehouseecc30c72008-01-28 10:37:35 +00001019 unsigned int height = ip->i_height;
Steven Whitehousecd915492006-09-04 12:49:07 -04001020 u64 lblock;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001021 struct metapath mp;
1022 int error;
1023
1024 if (!size)
1025 lblock = 0;
Steven Whitehouse18ec7d52006-02-08 11:50:51 +00001026 else
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +00001027 lblock = (size - 1) >> sdp->sd_sb.sb_bsize_shift;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001028
Steven Whitehouse9b8c81d2008-02-22 16:09:31 +00001029 find_metapath(sdp, lblock, &mp, ip->i_height);
Cyrill Gorcunov182fe5a2008-03-03 21:54:21 +03001030 if (!gfs2_alloc_get(ip))
1031 return -ENOMEM;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001032
1033 error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1034 if (error)
1035 goto out;
1036
1037 while (height--) {
1038 struct strip_mine sm;
1039 sm.sm_first = !!size;
1040 sm.sm_height = height;
1041
1042 error = recursive_scan(ip, NULL, &mp, 0, 0, 1, do_strip, &sm);
1043 if (error)
1044 break;
1045 }
1046
1047 gfs2_quota_unhold(ip);
1048
Steven Whitehousea91ea692006-09-04 12:04:26 -04001049out:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001050 gfs2_alloc_put(ip);
1051 return error;
1052}
1053
1054static int trunc_end(struct gfs2_inode *ip)
1055{
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -04001056 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001057 struct buffer_head *dibh;
1058 int error;
1059
1060 error = gfs2_trans_begin(sdp, RES_DINODE, 0);
1061 if (error)
1062 return error;
1063
1064 down_write(&ip->i_rw_mutex);
1065
1066 error = gfs2_meta_inode_buffer(ip, &dibh);
1067 if (error)
1068 goto out;
1069
Steven Whitehousea2e0f792010-08-11 09:53:11 +01001070 if (!i_size_read(&ip->i_inode)) {
Steven Whitehouseecc30c72008-01-28 10:37:35 +00001071 ip->i_height = 0;
Steven Whitehousece276b02008-02-06 09:25:45 +00001072 ip->i_goal = ip->i_no_addr;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001073 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
1074 }
Steven Whitehouse4bd91ba2007-06-05 09:39:18 +01001075 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
Steven Whitehouse383f01f2008-11-04 10:05:22 +00001076 ip->i_diskflags &= ~GFS2_DIF_TRUNC_IN_PROG;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001077
Steven Whitehoused4e9c4c2006-01-18 11:19:28 +00001078 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
Steven Whitehouse539e5d62006-10-31 15:07:05 -05001079 gfs2_dinode_out(ip, dibh->b_data);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001080 brelse(dibh);
1081
Steven Whitehousea91ea692006-09-04 12:04:26 -04001082out:
David Teiglandb3b94fa2006-01-16 16:50:04 +00001083 up_write(&ip->i_rw_mutex);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001084 gfs2_trans_end(sdp);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001085 return error;
1086}
1087
1088/**
1089 * do_shrink - make a file smaller
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001090 * @inode: the inode
1091 * @oldsize: the current inode size
1092 * @newsize: the size to make the file
David Teiglandb3b94fa2006-01-16 16:50:04 +00001093 *
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001094 * Called with an exclusive lock on @inode. The @size must
1095 * be equal to or smaller than the current inode size.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001096 *
1097 * Returns: errno
1098 */
1099
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001100static int do_shrink(struct inode *inode, u64 oldsize, u64 newsize)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001101{
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001102 struct gfs2_inode *ip = GFS2_I(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001103 int error;
1104
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001105 error = trunc_start(inode, oldsize, newsize);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001106 if (error < 0)
1107 return error;
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001108 if (gfs2_is_stuffed(ip))
David Teiglandb3b94fa2006-01-16 16:50:04 +00001109 return 0;
1110
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001111 error = trunc_dealloc(ip, newsize);
1112 if (error == 0)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001113 error = trunc_end(ip);
1114
1115 return error;
1116}
1117
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001118void gfs2_trim_blocks(struct inode *inode)
Wendy Chenga13b8c52007-08-20 09:29:53 -04001119{
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001120 u64 size = inode->i_size;
1121 int ret;
1122
1123 ret = do_shrink(inode, size, size);
1124 WARN_ON(ret != 0);
1125}
1126
1127/**
1128 * do_grow - Touch and update inode size
1129 * @inode: The inode
1130 * @size: The new size
1131 *
1132 * This function updates the timestamps on the inode and
1133 * may also increase the size of the inode. This function
1134 * must not be called with @size any smaller than the current
1135 * inode size.
1136 *
1137 * Although it is not strictly required to unstuff files here,
1138 * earlier versions of GFS2 have a bug in the stuffed file reading
1139 * code which will result in a buffer overrun if the size is larger
1140 * than the max stuffed file size. In order to prevent this from
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001141 * occurring, such files are unstuffed, but in other cases we can
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001142 * just update the inode size directly.
1143 *
1144 * Returns: 0 on success, or -ve on error
1145 */
1146
1147static int do_grow(struct inode *inode, u64 size)
1148{
1149 struct gfs2_inode *ip = GFS2_I(inode);
1150 struct gfs2_sbd *sdp = GFS2_SB(inode);
Wendy Chenga13b8c52007-08-20 09:29:53 -04001151 struct buffer_head *dibh;
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001152 struct gfs2_alloc *al = NULL;
Wendy Chenga13b8c52007-08-20 09:29:53 -04001153 int error;
1154
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001155 if (gfs2_is_stuffed(ip) &&
1156 (size > (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)))) {
1157 al = gfs2_alloc_get(ip);
1158 if (al == NULL)
1159 return -ENOMEM;
Wendy Chenga13b8c52007-08-20 09:29:53 -04001160
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001161 error = gfs2_quota_lock_check(ip);
1162 if (error)
1163 goto do_grow_alloc_put;
1164
1165 al->al_requested = 1;
1166 error = gfs2_inplace_reserve(ip);
1167 if (error)
1168 goto do_grow_qunlock;
1169 }
1170
Benjamin Marzinskibf97b672010-09-27 16:00:04 -05001171 error = gfs2_trans_begin(sdp, RES_DINODE + RES_STATFS + RES_RG_BIT, 0);
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001172 if (error)
1173 goto do_grow_release;
1174
1175 if (al) {
1176 error = gfs2_unstuff_dinode(ip, NULL);
1177 if (error)
1178 goto do_end_trans;
1179 }
Wendy Chenga13b8c52007-08-20 09:29:53 -04001180
1181 error = gfs2_meta_inode_buffer(ip, &dibh);
1182 if (error)
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001183 goto do_end_trans;
Wendy Chenga13b8c52007-08-20 09:29:53 -04001184
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001185 i_size_write(inode, size);
Wendy Chenga13b8c52007-08-20 09:29:53 -04001186 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME;
1187 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1188 gfs2_dinode_out(ip, dibh->b_data);
1189 brelse(dibh);
1190
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001191do_end_trans:
Wendy Chenga13b8c52007-08-20 09:29:53 -04001192 gfs2_trans_end(sdp);
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001193do_grow_release:
1194 if (al) {
1195 gfs2_inplace_release(ip);
1196do_grow_qunlock:
1197 gfs2_quota_unlock(ip);
1198do_grow_alloc_put:
1199 gfs2_alloc_put(ip);
1200 }
Wendy Chenga13b8c52007-08-20 09:29:53 -04001201 return error;
1202}
1203
David Teiglandb3b94fa2006-01-16 16:50:04 +00001204/**
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001205 * gfs2_setattr_size - make a file a given size
1206 * @inode: the inode
1207 * @newsize: the size to make the file
David Teiglandb3b94fa2006-01-16 16:50:04 +00001208 *
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001209 * The file size can grow, shrink, or stay the same size. This
1210 * is called holding i_mutex and an exclusive glock on the inode
1211 * in question.
David Teiglandb3b94fa2006-01-16 16:50:04 +00001212 *
1213 * Returns: errno
1214 */
1215
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001216int gfs2_setattr_size(struct inode *inode, u64 newsize)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001217{
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001218 int ret;
1219 u64 oldsize;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001220
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001221 BUG_ON(!S_ISREG(inode->i_mode));
David Teiglandb3b94fa2006-01-16 16:50:04 +00001222
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001223 ret = inode_newsize_ok(inode, newsize);
1224 if (ret)
1225 return ret;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001226
Steven Whitehouseff8f33c2010-08-11 09:37:53 +01001227 oldsize = inode->i_size;
1228 if (newsize >= oldsize)
1229 return do_grow(inode, newsize);
1230
1231 return do_shrink(inode, oldsize, newsize);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001232}
1233
1234int gfs2_truncatei_resume(struct gfs2_inode *ip)
1235{
1236 int error;
Steven Whitehousea2e0f792010-08-11 09:53:11 +01001237 error = trunc_dealloc(ip, i_size_read(&ip->i_inode));
David Teiglandb3b94fa2006-01-16 16:50:04 +00001238 if (!error)
1239 error = trunc_end(ip);
1240 return error;
1241}
1242
1243int gfs2_file_dealloc(struct gfs2_inode *ip)
1244{
1245 return trunc_dealloc(ip, 0);
1246}
1247
1248/**
David Teiglandb3b94fa2006-01-16 16:50:04 +00001249 * gfs2_write_alloc_required - figure out if a write will require an allocation
1250 * @ip: the file being written to
1251 * @offset: the offset to write to
1252 * @len: the number of bytes being written
David Teiglandb3b94fa2006-01-16 16:50:04 +00001253 *
Bob Peterson461cb412010-06-24 19:21:20 -04001254 * Returns: 1 if an alloc is required, 0 otherwise
David Teiglandb3b94fa2006-01-16 16:50:04 +00001255 */
1256
Steven Whitehousecd915492006-09-04 12:49:07 -04001257int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
Bob Peterson461cb412010-06-24 19:21:20 -04001258 unsigned int len)
David Teiglandb3b94fa2006-01-16 16:50:04 +00001259{
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -04001260 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
Steven Whitehouse941e6d72008-01-28 08:47:38 +00001261 struct buffer_head bh;
1262 unsigned int shift;
1263 u64 lblock, lblock_stop, size;
Steven Whitehouse7ed122e2008-12-10 10:28:10 +00001264 u64 end_of_file;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001265
David Teiglandb3b94fa2006-01-16 16:50:04 +00001266 if (!len)
1267 return 0;
1268
1269 if (gfs2_is_stuffed(ip)) {
1270 if (offset + len >
1271 sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode))
Bob Peterson461cb412010-06-24 19:21:20 -04001272 return 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001273 return 0;
1274 }
1275
Steven Whitehouse941e6d72008-01-28 08:47:38 +00001276 shift = sdp->sd_sb.sb_bsize_shift;
Steven Whitehouse7ed122e2008-12-10 10:28:10 +00001277 BUG_ON(gfs2_is_dir(ip));
Steven Whitehousea2e0f792010-08-11 09:53:11 +01001278 end_of_file = (i_size_read(&ip->i_inode) + sdp->sd_sb.sb_bsize - 1) >> shift;
Steven Whitehouse7ed122e2008-12-10 10:28:10 +00001279 lblock = offset >> shift;
1280 lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift;
1281 if (lblock_stop > end_of_file)
Bob Peterson461cb412010-06-24 19:21:20 -04001282 return 1;
David Teiglandb3b94fa2006-01-16 16:50:04 +00001283
Steven Whitehouse941e6d72008-01-28 08:47:38 +00001284 size = (lblock_stop - lblock) << shift;
1285 do {
1286 bh.b_state = 0;
1287 bh.b_size = size;
1288 gfs2_block_map(&ip->i_inode, lblock, &bh, 0);
1289 if (!buffer_mapped(&bh))
Bob Peterson461cb412010-06-24 19:21:20 -04001290 return 1;
Steven Whitehouse941e6d72008-01-28 08:47:38 +00001291 size -= bh.b_size;
1292 lblock += (bh.b_size >> ip->i_inode.i_blkbits);
1293 } while(size > 0);
David Teiglandb3b94fa2006-01-16 16:50:04 +00001294
1295 return 0;
1296}
1297