1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) International Business Machines Corp., 2000-2004 |
4 | */ |
5 | |
6 | #include <linux/fs.h> |
7 | #include <linux/quotaops.h> |
8 | #include "jfs_incore.h" |
9 | #include "jfs_inode.h" |
10 | #include "jfs_superblock.h" |
11 | #include "jfs_dmap.h" |
12 | #include "jfs_extent.h" |
13 | #include "jfs_debug.h" |
14 | |
15 | /* |
16 | * forward references |
17 | */ |
18 | static int extBalloc(struct inode *, s64, s64 *, s64 *); |
19 | static s64 extRoundDown(s64 nb); |
20 | |
21 | #define DPD(a) (printk("(a): %d\n",(a))) |
22 | #define DPC(a) (printk("(a): %c\n",(a))) |
23 | #define DPL1(a) \ |
24 | { \ |
25 | if ((a) >> 32) \ |
26 | printk("(a): %x%08x ",(a)); \ |
27 | else \ |
28 | printk("(a): %x ",(a) << 32); \ |
29 | } |
30 | #define DPL(a) \ |
31 | { \ |
32 | if ((a) >> 32) \ |
33 | printk("(a): %x%08x\n",(a)); \ |
34 | else \ |
35 | printk("(a): %x\n",(a) << 32); \ |
36 | } |
37 | |
38 | #define DPD1(a) (printk("(a): %d ",(a))) |
39 | #define DPX(a) (printk("(a): %08x\n",(a))) |
40 | #define DPX1(a) (printk("(a): %08x ",(a))) |
41 | #define DPS(a) (printk("%s\n",(a))) |
42 | #define DPE(a) (printk("\nENTERING: %s\n",(a))) |
43 | #define DPE1(a) (printk("\nENTERING: %s",(a))) |
44 | #define DPS1(a) (printk(" %s ",(a))) |
45 | |
46 | |
47 | /* |
48 | * NAME: extAlloc() |
49 | * |
50 | * FUNCTION: allocate an extent for a specified page range within a |
51 | * file. |
52 | * |
53 | * PARAMETERS: |
54 | * ip - the inode of the file. |
55 | * xlen - requested extent length. |
56 | * pno - the starting page number with the file. |
57 | * xp - pointer to an xad. on entry, xad describes an |
58 | * extent that is used as an allocation hint if the |
59 | * xaddr of the xad is non-zero. on successful exit, |
60 | * the xad describes the newly allocated extent. |
61 | * abnr - bool indicating whether the newly allocated extent |
62 | * should be marked as allocated but not recorded. |
63 | * |
64 | * RETURN VALUES: |
65 | * 0 - success |
66 | * -EIO - i/o error. |
67 | * -ENOSPC - insufficient disk resources. |
68 | */ |
69 | int |
70 | extAlloc(struct inode *ip, s64 xlen, s64 pno, xad_t * xp, bool abnr) |
71 | { |
72 | struct jfs_sb_info *sbi = JFS_SBI(sb: ip->i_sb); |
73 | s64 nxlen, nxaddr, xoff, hint, xaddr = 0; |
74 | int rc; |
75 | int xflag; |
76 | |
77 | /* This blocks if we are low on resources */ |
78 | txBeginAnon(ip->i_sb); |
79 | |
80 | /* Avoid race with jfs_commit_inode() */ |
81 | mutex_lock(&JFS_IP(ip)->commit_mutex); |
82 | |
83 | /* validate extent length */ |
84 | if (xlen > MAXXLEN) |
85 | xlen = MAXXLEN; |
86 | |
87 | /* get the page's starting extent offset */ |
88 | xoff = pno << sbi->l2nbperpage; |
89 | |
90 | /* check if an allocation hint was provided */ |
91 | if ((hint = addressXAD(xp))) { |
92 | /* get the size of the extent described by the hint */ |
93 | nxlen = lengthXAD(xp); |
94 | |
95 | /* check if the hint is for the portion of the file |
96 | * immediately previous to the current allocation |
97 | * request and if hint extent has the same abnr |
98 | * value as the current request. if so, we can |
99 | * extend the hint extent to include the current |
100 | * extent if we can allocate the blocks immediately |
101 | * following the hint extent. |
102 | */ |
103 | if (offsetXAD(xp) + nxlen == xoff && |
104 | abnr == ((xp->flag & XAD_NOTRECORDED) ? true : false)) |
105 | xaddr = hint + nxlen; |
106 | |
107 | /* adjust the hint to the last block of the extent */ |
108 | hint += (nxlen - 1); |
109 | } |
110 | |
111 | /* allocate the disk blocks for the extent. initially, extBalloc() |
112 | * will try to allocate disk blocks for the requested size (xlen). |
113 | * if this fails (xlen contiguous free blocks not available), it'll |
114 | * try to allocate a smaller number of blocks (producing a smaller |
115 | * extent), with this smaller number of blocks consisting of the |
116 | * requested number of blocks rounded down to the next smaller |
117 | * power of 2 number (i.e. 16 -> 8). it'll continue to round down |
118 | * and retry the allocation until the number of blocks to allocate |
119 | * is smaller than the number of blocks per page. |
120 | */ |
121 | nxlen = xlen; |
122 | if ((rc = extBalloc(ip, hint ? hint : INOHINT(ip), &nxlen, &nxaddr))) { |
123 | mutex_unlock(lock: &JFS_IP(inode: ip)->commit_mutex); |
124 | return (rc); |
125 | } |
126 | |
127 | /* Allocate blocks to quota. */ |
128 | rc = dquot_alloc_block(inode: ip, nr: nxlen); |
129 | if (rc) { |
130 | dbFree(ipbmap: ip, blkno: nxaddr, nblocks: (s64) nxlen); |
131 | mutex_unlock(lock: &JFS_IP(inode: ip)->commit_mutex); |
132 | return rc; |
133 | } |
134 | |
135 | /* determine the value of the extent flag */ |
136 | xflag = abnr ? XAD_NOTRECORDED : 0; |
137 | |
138 | /* if we can extend the hint extent to cover the current request, |
139 | * extend it. otherwise, insert a new extent to |
140 | * cover the current request. |
141 | */ |
142 | if (xaddr && xaddr == nxaddr) |
143 | rc = xtExtend(tid: 0, ip, xoff, xlen: (int) nxlen, flag: 0); |
144 | else |
145 | rc = xtInsert(tid: 0, ip, xflag, xoff, xlen: (int) nxlen, xaddrp: &nxaddr, flag: 0); |
146 | |
147 | /* if the extend or insert failed, |
148 | * free the newly allocated blocks and return the error. |
149 | */ |
150 | if (rc) { |
151 | dbFree(ipbmap: ip, blkno: nxaddr, nblocks: nxlen); |
152 | dquot_free_block(inode: ip, nr: nxlen); |
153 | mutex_unlock(lock: &JFS_IP(inode: ip)->commit_mutex); |
154 | return (rc); |
155 | } |
156 | |
157 | /* set the results of the extent allocation */ |
158 | XADaddress(xp, nxaddr); |
159 | XADlength(xp, nxlen); |
160 | XADoffset(xp, xoff); |
161 | xp->flag = xflag; |
162 | |
163 | mark_inode_dirty(inode: ip); |
164 | |
165 | mutex_unlock(lock: &JFS_IP(inode: ip)->commit_mutex); |
166 | /* |
167 | * COMMIT_SyncList flags an anonymous tlock on page that is on |
168 | * sync list. |
169 | * We need to commit the inode to get the page written to the disk. |
170 | */ |
171 | if (test_and_clear_cflag(COMMIT_Synclist,ip)) |
172 | jfs_commit_inode(ip, 0); |
173 | |
174 | return (0); |
175 | } |
176 | |
177 | /* |
178 | * NAME: extHint() |
179 | * |
180 | * FUNCTION: produce an extent allocation hint for a file offset. |
181 | * |
182 | * PARAMETERS: |
183 | * ip - the inode of the file. |
184 | * offset - file offset for which the hint is needed. |
185 | * xp - pointer to the xad that is to be filled in with |
186 | * the hint. |
187 | * |
188 | * RETURN VALUES: |
189 | * 0 - success |
190 | * -EIO - i/o error. |
191 | */ |
192 | int extHint(struct inode *ip, s64 offset, xad_t * xp) |
193 | { |
194 | struct super_block *sb = ip->i_sb; |
195 | int nbperpage = JFS_SBI(sb)->nbperpage; |
196 | s64 prev; |
197 | int rc = 0; |
198 | s64 xaddr; |
199 | int xlen; |
200 | int xflag; |
201 | |
202 | /* init the hint as "no hint provided" */ |
203 | XADaddress(xp, 0); |
204 | |
205 | /* determine the starting extent offset of the page previous |
206 | * to the page containing the offset. |
207 | */ |
208 | prev = ((offset & ~POFFSET) >> JFS_SBI(sb)->l2bsize) - nbperpage; |
209 | |
210 | /* if the offset is in the first page of the file, no hint provided. |
211 | */ |
212 | if (prev < 0) |
213 | goto out; |
214 | |
215 | rc = xtLookup(ip, lstart: prev, llen: nbperpage, pflag: &xflag, paddr: &xaddr, plen: &xlen, flag: 0); |
216 | |
217 | if ((rc == 0) && xlen) { |
218 | if (xlen != nbperpage) { |
219 | jfs_error(ip->i_sb, "corrupt xtree\n" ); |
220 | rc = -EIO; |
221 | } |
222 | XADaddress(xp, xaddr); |
223 | XADlength(xp, xlen); |
224 | XADoffset(xp, prev); |
225 | /* |
226 | * only preserve the abnr flag within the xad flags |
227 | * of the returned hint. |
228 | */ |
229 | xp->flag = xflag & XAD_NOTRECORDED; |
230 | } else |
231 | rc = 0; |
232 | |
233 | out: |
234 | return (rc); |
235 | } |
236 | |
237 | |
238 | /* |
239 | * NAME: extRecord() |
240 | * |
241 | * FUNCTION: change a page with a file from not recorded to recorded. |
242 | * |
243 | * PARAMETERS: |
244 | * ip - inode of the file. |
245 | * cp - cbuf of the file page. |
246 | * |
247 | * RETURN VALUES: |
248 | * 0 - success |
249 | * -EIO - i/o error. |
250 | * -ENOSPC - insufficient disk resources. |
251 | */ |
252 | int extRecord(struct inode *ip, xad_t * xp) |
253 | { |
254 | int rc; |
255 | |
256 | txBeginAnon(ip->i_sb); |
257 | |
258 | mutex_lock(&JFS_IP(ip)->commit_mutex); |
259 | |
260 | /* update the extent */ |
261 | rc = xtUpdate(tid: 0, ip, nxad: xp); |
262 | |
263 | mutex_unlock(lock: &JFS_IP(inode: ip)->commit_mutex); |
264 | return rc; |
265 | } |
266 | |
267 | /* |
268 | * NAME: extBalloc() |
269 | * |
270 | * FUNCTION: allocate disk blocks to form an extent. |
271 | * |
272 | * initially, we will try to allocate disk blocks for the |
273 | * requested size (nblocks). if this fails (nblocks |
274 | * contiguous free blocks not available), we'll try to allocate |
275 | * a smaller number of blocks (producing a smaller extent), with |
276 | * this smaller number of blocks consisting of the requested |
277 | * number of blocks rounded down to the next smaller power of 2 |
278 | * number (i.e. 16 -> 8). we'll continue to round down and |
279 | * retry the allocation until the number of blocks to allocate |
280 | * is smaller than the number of blocks per page. |
281 | * |
282 | * PARAMETERS: |
283 | * ip - the inode of the file. |
284 | * hint - disk block number to be used as an allocation hint. |
285 | * *nblocks - pointer to an s64 value. on entry, this value specifies |
286 | * the desired number of block to be allocated. on successful |
287 | * exit, this value is set to the number of blocks actually |
288 | * allocated. |
289 | * blkno - pointer to a block address that is filled in on successful |
290 | * return with the starting block number of the newly |
291 | * allocated block range. |
292 | * |
293 | * RETURN VALUES: |
294 | * 0 - success |
295 | * -EIO - i/o error. |
296 | * -ENOSPC - insufficient disk resources. |
297 | */ |
298 | static int |
299 | extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno) |
300 | { |
301 | struct jfs_inode_info *ji = JFS_IP(inode: ip); |
302 | struct jfs_sb_info *sbi = JFS_SBI(sb: ip->i_sb); |
303 | s64 nb, nblks, daddr, max; |
304 | int rc, nbperpage = sbi->nbperpage; |
305 | struct bmap *bmp = sbi->bmap; |
306 | int ag; |
307 | |
308 | /* get the number of blocks to initially attempt to allocate. |
309 | * we'll first try the number of blocks requested unless this |
310 | * number is greater than the maximum number of contiguous free |
311 | * blocks in the map. in that case, we'll start off with the |
312 | * maximum free. |
313 | */ |
314 | |
315 | /* give up if no space left */ |
316 | if (bmp->db_maxfreebud == -1) |
317 | return -ENOSPC; |
318 | |
319 | max = (s64) 1 << bmp->db_maxfreebud; |
320 | if (*nblocks >= max && *nblocks > nbperpage) |
321 | nb = nblks = (max > nbperpage) ? max : nbperpage; |
322 | else |
323 | nb = nblks = *nblocks; |
324 | |
325 | /* try to allocate blocks */ |
326 | while ((rc = dbAlloc(ipbmap: ip, hint, nblocks: nb, results: &daddr)) != 0) { |
327 | /* if something other than an out of space error, |
328 | * stop and return this error. |
329 | */ |
330 | if (rc != -ENOSPC) |
331 | return (rc); |
332 | |
333 | /* decrease the allocation request size */ |
334 | nb = min(nblks, extRoundDown(nb)); |
335 | |
336 | /* give up if we cannot cover a page */ |
337 | if (nb < nbperpage) |
338 | return (rc); |
339 | } |
340 | |
341 | *nblocks = nb; |
342 | *blkno = daddr; |
343 | |
344 | if (S_ISREG(ip->i_mode) && (ji->fileset == FILESYSTEM_I)) { |
345 | ag = BLKTOAG(daddr, sbi); |
346 | spin_lock_irq(lock: &ji->ag_lock); |
347 | if (ji->active_ag == -1) { |
348 | atomic_inc(v: &bmp->db_active[ag]); |
349 | ji->active_ag = ag; |
350 | } else if (ji->active_ag != ag) { |
351 | atomic_dec(v: &bmp->db_active[ji->active_ag]); |
352 | atomic_inc(v: &bmp->db_active[ag]); |
353 | ji->active_ag = ag; |
354 | } |
355 | spin_unlock_irq(lock: &ji->ag_lock); |
356 | } |
357 | |
358 | return (0); |
359 | } |
360 | |
361 | /* |
362 | * NAME: extRoundDown() |
363 | * |
364 | * FUNCTION: round down a specified number of blocks to the next |
365 | * smallest power of 2 number. |
366 | * |
367 | * PARAMETERS: |
368 | * nb - the inode of the file. |
369 | * |
370 | * RETURN VALUES: |
371 | * next smallest power of 2 number. |
372 | */ |
373 | static s64 extRoundDown(s64 nb) |
374 | { |
375 | int i; |
376 | u64 m, k; |
377 | |
378 | for (i = 0, m = (u64) 1 << 63; i < 64; i++, m >>= 1) { |
379 | if (m & nb) |
380 | break; |
381 | } |
382 | |
383 | i = 63 - i; |
384 | k = (u64) 1 << i; |
385 | k = ((k - 1) & nb) ? k : k >> 1; |
386 | |
387 | return (k); |
388 | } |
389 | |