Linux-libre 4.19.20-gnu
[librecmc/linux-libre.git] / fs / xfs / libxfs / xfs_ag.c
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4  * Copyright (c) 2018 Red Hat, Inc.
5  * All rights reserved.
6  */
7
8 #include "xfs.h"
9 #include "xfs_fs.h"
10 #include "xfs_shared.h"
11 #include "xfs_format.h"
12 #include "xfs_trans_resv.h"
13 #include "xfs_sb.h"
14 #include "xfs_mount.h"
15 #include "xfs_btree.h"
16 #include "xfs_alloc_btree.h"
17 #include "xfs_rmap_btree.h"
18 #include "xfs_alloc.h"
19 #include "xfs_ialloc.h"
20 #include "xfs_rmap.h"
21 #include "xfs_ag.h"
22
23 static struct xfs_buf *
24 xfs_get_aghdr_buf(
25         struct xfs_mount        *mp,
26         xfs_daddr_t             blkno,
27         size_t                  numblks,
28         int                     flags,
29         const struct xfs_buf_ops *ops)
30 {
31         struct xfs_buf          *bp;
32
33         bp = xfs_buf_get_uncached(mp->m_ddev_targp, numblks, flags);
34         if (!bp)
35                 return NULL;
36
37         xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
38         bp->b_bn = blkno;
39         bp->b_maps[0].bm_bn = blkno;
40         bp->b_ops = ops;
41
42         return bp;
43 }
44
45 /*
46  * Generic btree root block init function
47  */
48 static void
49 xfs_btroot_init(
50         struct xfs_mount        *mp,
51         struct xfs_buf          *bp,
52         struct aghdr_init_data  *id)
53 {
54         xfs_btree_init_block(mp, bp, id->type, 0, 0, id->agno, 0);
55 }
56
57 /*
58  * Alloc btree root block init functions
59  */
60 static void
61 xfs_bnoroot_init(
62         struct xfs_mount        *mp,
63         struct xfs_buf          *bp,
64         struct aghdr_init_data  *id)
65 {
66         struct xfs_alloc_rec    *arec;
67
68         xfs_btree_init_block(mp, bp, XFS_BTNUM_BNO, 0, 1, id->agno, 0);
69         arec = XFS_ALLOC_REC_ADDR(mp, XFS_BUF_TO_BLOCK(bp), 1);
70         arec->ar_startblock = cpu_to_be32(mp->m_ag_prealloc_blocks);
71         arec->ar_blockcount = cpu_to_be32(id->agsize -
72                                           be32_to_cpu(arec->ar_startblock));
73 }
74
75 static void
76 xfs_cntroot_init(
77         struct xfs_mount        *mp,
78         struct xfs_buf          *bp,
79         struct aghdr_init_data  *id)
80 {
81         struct xfs_alloc_rec    *arec;
82
83         xfs_btree_init_block(mp, bp, XFS_BTNUM_CNT, 0, 1, id->agno, 0);
84         arec = XFS_ALLOC_REC_ADDR(mp, XFS_BUF_TO_BLOCK(bp), 1);
85         arec->ar_startblock = cpu_to_be32(mp->m_ag_prealloc_blocks);
86         arec->ar_blockcount = cpu_to_be32(id->agsize -
87                                           be32_to_cpu(arec->ar_startblock));
88 }
89
90 /*
91  * Reverse map root block init
92  */
93 static void
94 xfs_rmaproot_init(
95         struct xfs_mount        *mp,
96         struct xfs_buf          *bp,
97         struct aghdr_init_data  *id)
98 {
99         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
100         struct xfs_rmap_rec     *rrec;
101
102         xfs_btree_init_block(mp, bp, XFS_BTNUM_RMAP, 0, 4, id->agno, 0);
103
104         /*
105          * mark the AG header regions as static metadata The BNO
106          * btree block is the first block after the headers, so
107          * it's location defines the size of region the static
108          * metadata consumes.
109          *
110          * Note: unlike mkfs, we never have to account for log
111          * space when growing the data regions
112          */
113         rrec = XFS_RMAP_REC_ADDR(block, 1);
114         rrec->rm_startblock = 0;
115         rrec->rm_blockcount = cpu_to_be32(XFS_BNO_BLOCK(mp));
116         rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_FS);
117         rrec->rm_offset = 0;
118
119         /* account freespace btree root blocks */
120         rrec = XFS_RMAP_REC_ADDR(block, 2);
121         rrec->rm_startblock = cpu_to_be32(XFS_BNO_BLOCK(mp));
122         rrec->rm_blockcount = cpu_to_be32(2);
123         rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_AG);
124         rrec->rm_offset = 0;
125
126         /* account inode btree root blocks */
127         rrec = XFS_RMAP_REC_ADDR(block, 3);
128         rrec->rm_startblock = cpu_to_be32(XFS_IBT_BLOCK(mp));
129         rrec->rm_blockcount = cpu_to_be32(XFS_RMAP_BLOCK(mp) -
130                                           XFS_IBT_BLOCK(mp));
131         rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_INOBT);
132         rrec->rm_offset = 0;
133
134         /* account for rmap btree root */
135         rrec = XFS_RMAP_REC_ADDR(block, 4);
136         rrec->rm_startblock = cpu_to_be32(XFS_RMAP_BLOCK(mp));
137         rrec->rm_blockcount = cpu_to_be32(1);
138         rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_AG);
139         rrec->rm_offset = 0;
140
141         /* account for refc btree root */
142         if (xfs_sb_version_hasreflink(&mp->m_sb)) {
143                 rrec = XFS_RMAP_REC_ADDR(block, 5);
144                 rrec->rm_startblock = cpu_to_be32(xfs_refc_block(mp));
145                 rrec->rm_blockcount = cpu_to_be32(1);
146                 rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_REFC);
147                 rrec->rm_offset = 0;
148                 be16_add_cpu(&block->bb_numrecs, 1);
149         }
150 }
151
152 /*
153  * Initialise new secondary superblocks with the pre-grow geometry, but mark
154  * them as "in progress" so we know they haven't yet been activated. This will
155  * get cleared when the update with the new geometry information is done after
156  * changes to the primary are committed. This isn't strictly necessary, but we
157  * get it for free with the delayed buffer write lists and it means we can tell
158  * if a grow operation didn't complete properly after the fact.
159  */
160 static void
161 xfs_sbblock_init(
162         struct xfs_mount        *mp,
163         struct xfs_buf          *bp,
164         struct aghdr_init_data  *id)
165 {
166         struct xfs_dsb          *dsb = XFS_BUF_TO_SBP(bp);
167
168         xfs_sb_to_disk(dsb, &mp->m_sb);
169         dsb->sb_inprogress = 1;
170 }
171
172 static void
173 xfs_agfblock_init(
174         struct xfs_mount        *mp,
175         struct xfs_buf          *bp,
176         struct aghdr_init_data  *id)
177 {
178         struct xfs_agf          *agf = XFS_BUF_TO_AGF(bp);
179         xfs_extlen_t            tmpsize;
180
181         agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
182         agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
183         agf->agf_seqno = cpu_to_be32(id->agno);
184         agf->agf_length = cpu_to_be32(id->agsize);
185         agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
186         agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
187         agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
188         agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
189         if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
190                 agf->agf_roots[XFS_BTNUM_RMAPi] =
191                                         cpu_to_be32(XFS_RMAP_BLOCK(mp));
192                 agf->agf_levels[XFS_BTNUM_RMAPi] = cpu_to_be32(1);
193                 agf->agf_rmap_blocks = cpu_to_be32(1);
194         }
195
196         agf->agf_flfirst = cpu_to_be32(1);
197         agf->agf_fllast = 0;
198         agf->agf_flcount = 0;
199         tmpsize = id->agsize - mp->m_ag_prealloc_blocks;
200         agf->agf_freeblks = cpu_to_be32(tmpsize);
201         agf->agf_longest = cpu_to_be32(tmpsize);
202         if (xfs_sb_version_hascrc(&mp->m_sb))
203                 uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid);
204         if (xfs_sb_version_hasreflink(&mp->m_sb)) {
205                 agf->agf_refcount_root = cpu_to_be32(
206                                 xfs_refc_block(mp));
207                 agf->agf_refcount_level = cpu_to_be32(1);
208                 agf->agf_refcount_blocks = cpu_to_be32(1);
209         }
210 }
211
212 static void
213 xfs_agflblock_init(
214         struct xfs_mount        *mp,
215         struct xfs_buf          *bp,
216         struct aghdr_init_data  *id)
217 {
218         struct xfs_agfl         *agfl = XFS_BUF_TO_AGFL(bp);
219         __be32                  *agfl_bno;
220         int                     bucket;
221
222         if (xfs_sb_version_hascrc(&mp->m_sb)) {
223                 agfl->agfl_magicnum = cpu_to_be32(XFS_AGFL_MAGIC);
224                 agfl->agfl_seqno = cpu_to_be32(id->agno);
225                 uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid);
226         }
227
228         agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, bp);
229         for (bucket = 0; bucket < xfs_agfl_size(mp); bucket++)
230                 agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);
231 }
232
233 static void
234 xfs_agiblock_init(
235         struct xfs_mount        *mp,
236         struct xfs_buf          *bp,
237         struct aghdr_init_data  *id)
238 {
239         struct xfs_agi          *agi = XFS_BUF_TO_AGI(bp);
240         int                     bucket;
241
242         agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
243         agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
244         agi->agi_seqno = cpu_to_be32(id->agno);
245         agi->agi_length = cpu_to_be32(id->agsize);
246         agi->agi_count = 0;
247         agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
248         agi->agi_level = cpu_to_be32(1);
249         agi->agi_freecount = 0;
250         agi->agi_newino = cpu_to_be32(NULLAGINO);
251         agi->agi_dirino = cpu_to_be32(NULLAGINO);
252         if (xfs_sb_version_hascrc(&mp->m_sb))
253                 uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid);
254         if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
255                 agi->agi_free_root = cpu_to_be32(XFS_FIBT_BLOCK(mp));
256                 agi->agi_free_level = cpu_to_be32(1);
257         }
258         for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
259                 agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
260 }
261
262 typedef void (*aghdr_init_work_f)(struct xfs_mount *mp, struct xfs_buf *bp,
263                                   struct aghdr_init_data *id);
264 static int
265 xfs_ag_init_hdr(
266         struct xfs_mount        *mp,
267         struct aghdr_init_data  *id,
268         aghdr_init_work_f       work,
269         const struct xfs_buf_ops *ops)
270
271 {
272         struct xfs_buf          *bp;
273
274         bp = xfs_get_aghdr_buf(mp, id->daddr, id->numblks, 0, ops);
275         if (!bp)
276                 return -ENOMEM;
277
278         (*work)(mp, bp, id);
279
280         xfs_buf_delwri_queue(bp, &id->buffer_list);
281         xfs_buf_relse(bp);
282         return 0;
283 }
284
285 struct xfs_aghdr_grow_data {
286         xfs_daddr_t             daddr;
287         size_t                  numblks;
288         const struct xfs_buf_ops *ops;
289         aghdr_init_work_f       work;
290         xfs_btnum_t             type;
291         bool                    need_init;
292 };
293
294 /*
295  * Prepare new AG headers to be written to disk. We use uncached buffers here,
296  * as it is assumed these new AG headers are currently beyond the currently
297  * valid filesystem address space. Using cached buffers would trip over EOFS
298  * corruption detection alogrithms in the buffer cache lookup routines.
299  *
300  * This is a non-transactional function, but the prepared buffers are added to a
301  * delayed write buffer list supplied by the caller so they can submit them to
302  * disk and wait on them as required.
303  */
304 int
305 xfs_ag_init_headers(
306         struct xfs_mount        *mp,
307         struct aghdr_init_data  *id)
308
309 {
310         struct xfs_aghdr_grow_data aghdr_data[] = {
311         { /* SB */
312                 .daddr = XFS_AG_DADDR(mp, id->agno, XFS_SB_DADDR),
313                 .numblks = XFS_FSS_TO_BB(mp, 1),
314                 .ops = &xfs_sb_buf_ops,
315                 .work = &xfs_sbblock_init,
316                 .need_init = true
317         },
318         { /* AGF */
319                 .daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGF_DADDR(mp)),
320                 .numblks = XFS_FSS_TO_BB(mp, 1),
321                 .ops = &xfs_agf_buf_ops,
322                 .work = &xfs_agfblock_init,
323                 .need_init = true
324         },
325         { /* AGFL */
326                 .daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGFL_DADDR(mp)),
327                 .numblks = XFS_FSS_TO_BB(mp, 1),
328                 .ops = &xfs_agfl_buf_ops,
329                 .work = &xfs_agflblock_init,
330                 .need_init = true
331         },
332         { /* AGI */
333                 .daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGI_DADDR(mp)),
334                 .numblks = XFS_FSS_TO_BB(mp, 1),
335                 .ops = &xfs_agi_buf_ops,
336                 .work = &xfs_agiblock_init,
337                 .need_init = true
338         },
339         { /* BNO root block */
340                 .daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_BNO_BLOCK(mp)),
341                 .numblks = BTOBB(mp->m_sb.sb_blocksize),
342                 .ops = &xfs_allocbt_buf_ops,
343                 .work = &xfs_bnoroot_init,
344                 .need_init = true
345         },
346         { /* CNT root block */
347                 .daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_CNT_BLOCK(mp)),
348                 .numblks = BTOBB(mp->m_sb.sb_blocksize),
349                 .ops = &xfs_allocbt_buf_ops,
350                 .work = &xfs_cntroot_init,
351                 .need_init = true
352         },
353         { /* INO root block */
354                 .daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_IBT_BLOCK(mp)),
355                 .numblks = BTOBB(mp->m_sb.sb_blocksize),
356                 .ops = &xfs_inobt_buf_ops,
357                 .work = &xfs_btroot_init,
358                 .type = XFS_BTNUM_INO,
359                 .need_init = true
360         },
361         { /* FINO root block */
362                 .daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_FIBT_BLOCK(mp)),
363                 .numblks = BTOBB(mp->m_sb.sb_blocksize),
364                 .ops = &xfs_inobt_buf_ops,
365                 .work = &xfs_btroot_init,
366                 .type = XFS_BTNUM_FINO,
367                 .need_init =  xfs_sb_version_hasfinobt(&mp->m_sb)
368         },
369         { /* RMAP root block */
370                 .daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_RMAP_BLOCK(mp)),
371                 .numblks = BTOBB(mp->m_sb.sb_blocksize),
372                 .ops = &xfs_rmapbt_buf_ops,
373                 .work = &xfs_rmaproot_init,
374                 .need_init = xfs_sb_version_hasrmapbt(&mp->m_sb)
375         },
376         { /* REFC root block */
377                 .daddr = XFS_AGB_TO_DADDR(mp, id->agno, xfs_refc_block(mp)),
378                 .numblks = BTOBB(mp->m_sb.sb_blocksize),
379                 .ops = &xfs_refcountbt_buf_ops,
380                 .work = &xfs_btroot_init,
381                 .type = XFS_BTNUM_REFC,
382                 .need_init = xfs_sb_version_hasreflink(&mp->m_sb)
383         },
384         { /* NULL terminating block */
385                 .daddr = XFS_BUF_DADDR_NULL,
386         }
387         };
388         struct  xfs_aghdr_grow_data *dp;
389         int                     error = 0;
390
391         /* Account for AG free space in new AG */
392         id->nfree += id->agsize - mp->m_ag_prealloc_blocks;
393         for (dp = &aghdr_data[0]; dp->daddr != XFS_BUF_DADDR_NULL; dp++) {
394                 if (!dp->need_init)
395                         continue;
396
397                 id->daddr = dp->daddr;
398                 id->numblks = dp->numblks;
399                 id->type = dp->type;
400                 error = xfs_ag_init_hdr(mp, id, dp->work, dp->ops);
401                 if (error)
402                         break;
403         }
404         return error;
405 }
406
407 /*
408  * Extent the AG indicated by the @id by the length passed in
409  */
410 int
411 xfs_ag_extend_space(
412         struct xfs_mount        *mp,
413         struct xfs_trans        *tp,
414         struct aghdr_init_data  *id,
415         xfs_extlen_t            len)
416 {
417         struct xfs_owner_info   oinfo;
418         struct xfs_buf          *bp;
419         struct xfs_agi          *agi;
420         struct xfs_agf          *agf;
421         int                     error;
422
423         /*
424          * Change the agi length.
425          */
426         error = xfs_ialloc_read_agi(mp, tp, id->agno, &bp);
427         if (error)
428                 return error;
429
430         agi = XFS_BUF_TO_AGI(bp);
431         be32_add_cpu(&agi->agi_length, len);
432         ASSERT(id->agno == mp->m_sb.sb_agcount - 1 ||
433                be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
434         xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
435
436         /*
437          * Change agf length.
438          */
439         error = xfs_alloc_read_agf(mp, tp, id->agno, 0, &bp);
440         if (error)
441                 return error;
442
443         agf = XFS_BUF_TO_AGF(bp);
444         be32_add_cpu(&agf->agf_length, len);
445         ASSERT(agf->agf_length == agi->agi_length);
446         xfs_alloc_log_agf(tp, bp, XFS_AGF_LENGTH);
447
448         /*
449          * Free the new space.
450          *
451          * XFS_RMAP_OWN_NULL is used here to tell the rmap btree that
452          * this doesn't actually exist in the rmap btree.
453          */
454         xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_NULL);
455         error = xfs_rmap_free(tp, bp, id->agno,
456                                 be32_to_cpu(agf->agf_length) - len,
457                                 len, &oinfo);
458         if (error)
459                 return error;
460
461         return  xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, id->agno,
462                                         be32_to_cpu(agf->agf_length) - len),
463                                 len, &oinfo, XFS_AG_RESV_NONE);
464 }