Bug Summary

File:dev/softraid_raid5.c
Warning:line 729, column 29
Access to field 'swu_dis' results in a dereference of a null pointer (loaded from variable 'wu')

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name softraid_raid5.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model static -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -ffreestanding -mcmodel=kernel -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -target-feature -sse2 -target-feature -sse -target-feature -3dnow -target-feature -mmx -target-feature +save-args -disable-red-zone -no-implicit-float -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/sys/arch/amd64/compile/GENERIC.MP/obj -nostdsysteminc -nobuiltininc -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/sys -I /usr/src/sys/arch/amd64/compile/GENERIC.MP/obj -I /usr/src/sys/arch -I /usr/src/sys/dev/pci/drm/include -I /usr/src/sys/dev/pci/drm/include/uapi -I /usr/src/sys/dev/pci/drm/amd/include/asic_reg -I /usr/src/sys/dev/pci/drm/amd/include -I /usr/src/sys/dev/pci/drm/amd/amdgpu -I /usr/src/sys/dev/pci/drm/amd/display -I /usr/src/sys/dev/pci/drm/amd/display/include -I /usr/src/sys/dev/pci/drm/amd/display/dc -I /usr/src/sys/dev/pci/drm/amd/display/amdgpu_dm -I /usr/src/sys/dev/pci/drm/amd/pm/inc -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/smu11 -I /usr/src/sys/dev/pci/drm/amd/pm/swsmu/smu12 -I /usr/src/sys/dev/pci/drm/amd/pm/powerplay -I /usr/src/sys/dev/pci/drm/amd/pm/powerplay/hwmgr -I /usr/src/sys/dev/pci/drm/amd/pm/powerplay/smumgr -I /usr/src/sys/dev/pci/drm/amd/display/dc/inc -I /usr/src/sys/dev/pci/drm/amd/display/dc/inc/hw -I /usr/src/sys/dev/pci/drm/amd/display/dc/clk_mgr -I /usr/src/sys/dev/pci/drm/amd/display/modules/inc -I /usr/src/sys/dev/pci/drm/amd/display/modules/hdcp -I /usr/src/sys/dev/pci/drm/amd/display/dmub/inc -I /usr/src/sys/dev/pci/drm/i915 -D DDB -D DIAGNOSTIC -D KTRACE -D ACCOUNTING -D KMEMSTATS -D PTRACE -D POOL_DEBUG -D CRYPTO -D SYSVMSG -D SYSVSEM -D SYSVSHM -D UVM_SWAP_ENCRYPT -D FFS -D FFS2 -D FFS_SOFTUPDATES -D UFS_DIRHASH -D QUOTA -D EXT2FS -D MFS -D NFSCLIENT -D NFSSERVER -D CD9660 -D UDF -D MSDOSFS -D FIFO -D FUSE -D SOCKET_SPLICE -D TCP_ECN -D TCP_SIGNATURE -D INET6 -D IPSEC -D PPP_BSDCOMP -D PPP_DEFLATE -D PIPEX -D MROUTING -D MPLS -D BOOT_CONFIG -D USER_PCICONF -D APERTURE -D MTRR -D NTFS -D HIBERNATE -D PCIVERBOSE -D USBVERBOSE -D WSDISPLAY_COMPAT_USL -D WSDISPLAY_COMPAT_RAWKBD -D WSDISPLAY_DEFAULTSCREENS=6 -D X86EMU -D ONEWIREVERBOSE -D MULTIPROCESSOR -D MAXUSERS=80 -D _KERNEL -D CONFIG_DRM_AMD_DC_DCN3_0 -O2 -Wno-pointer-sign -Wno-address-of-packed-member -Wno-constant-conversion -Wno-unused-but-set-variable -Wno-gnu-folding-constant -fdebug-compilation-dir=/usr/src/sys/arch/amd64/compile/GENERIC.MP/obj -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -o /usr/obj/sys/arch/amd64/compile/GENERIC.MP/scan-build/2022-01-12-131800-47421-1 -x c /usr/src/sys/dev/softraid_raid5.c
1/* $OpenBSD: softraid_raid5.c,v 1.32 2021/05/16 15:12:37 deraadt Exp $ */
2/*
3 * Copyright (c) 2014 Joel Sing <jsing@openbsd.org>
4 * Copyright (c) 2009 Marco Peereboom <marco@peereboom.us>
5 * Copyright (c) 2009 Jordan Hargrave <jordan@openbsd.org>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20#include "bio.h"
21
22#include <sys/param.h>
23#include <sys/systm.h>
24#include <sys/buf.h>
25#include <sys/device.h>
26#include <sys/ioctl.h>
27#include <sys/malloc.h>
28#include <sys/kernel.h>
29#include <sys/disk.h>
30#include <sys/rwlock.h>
31#include <sys/queue.h>
32#include <sys/fcntl.h>
33#include <sys/mount.h>
34#include <sys/sensors.h>
35#include <sys/stat.h>
36#include <sys/task.h>
37#include <sys/pool.h>
38#include <sys/conf.h>
39#include <sys/uio.h>
40
41#include <scsi/scsi_all.h>
42#include <scsi/scsiconf.h>
43#include <scsi/scsi_disk.h>
44
45#include <dev/softraidvar.h>
46
47/* RAID 5 functions. */
48int sr_raid5_create(struct sr_discipline *, struct bioc_createraid *,
49 int, int64_t);
50int sr_raid5_assemble(struct sr_discipline *, struct bioc_createraid *,
51 int, void *);
52int sr_raid5_init(struct sr_discipline *);
53int sr_raid5_rw(struct sr_workunit *);
54int sr_raid5_openings(struct sr_discipline *);
55void sr_raid5_intr(struct buf *);
56int sr_raid5_wu_done(struct sr_workunit *);
57void sr_raid5_set_chunk_state(struct sr_discipline *, int, int);
58void sr_raid5_set_vol_state(struct sr_discipline *);
59
60int sr_raid5_addio(struct sr_workunit *wu, int, daddr_t, long,
61 void *, int, int, void *);
62int sr_raid5_regenerate(struct sr_workunit *, int, daddr_t, long,
63 void *);
64int sr_raid5_write(struct sr_workunit *, struct sr_workunit *, int, int,
65 daddr_t, long, void *, int, int);
66void sr_raid5_xor(void *, void *, int);
67
68void sr_raid5_rebuild(struct sr_discipline *);
69void sr_raid5_scrub(struct sr_discipline *);
70
71/* discipline initialisation. */
72void
73sr_raid5_discipline_init(struct sr_discipline *sd)
74{
75 /* Fill out discipline members. */
76 sd->sd_type = SR_MD_RAID52;
77 strlcpy(sd->sd_name, "RAID 5", sizeof(sd->sd_name));
78 sd->sd_capabilities = SR_CAP_SYSTEM_DISK0x00000001 | SR_CAP_AUTO_ASSEMBLE0x00000002 |
79 SR_CAP_REBUILD0x00000004 | SR_CAP_REDUNDANT0x00000010;
80 sd->sd_max_wu = SR_RAID5_NOWU16 + 2; /* Two for scrub/rebuild. */
81
82 /* Setup discipline specific function pointers. */
83 sd->sd_assemble = sr_raid5_assemble;
84 sd->sd_create = sr_raid5_create;
85 sd->sd_openings = sr_raid5_openings;
86 sd->sd_rebuild = sr_raid5_rebuild;
87 sd->sd_scsi_rw = sr_raid5_rw;
88 sd->sd_scsi_intr = sr_raid5_intr;
89 sd->sd_scsi_wu_done = sr_raid5_wu_done;
90 sd->sd_set_chunk_state = sr_raid5_set_chunk_state;
91 sd->sd_set_vol_state = sr_raid5_set_vol_state;
92}
93
94int
95sr_raid5_create(struct sr_discipline *sd, struct bioc_createraid *bc,
96 int no_chunk, int64_t coerced_size)
97{
98 if (no_chunk < 3) {
99 sr_error(sd->sd_sc, "%s requires three or more chunks",
100 sd->sd_name);
101 return EINVAL22;
102 }
103
104 /*
105 * XXX add variable strip size later even though MAXPHYS is really
106 * the clever value, users like to tinker with that type of stuff.
107 */
108 sd->sd_meta->ssdi_sdd_invariant.ssd_strip_size = MAXPHYS(64 * 1024);
109 sd->sd_meta->ssdi_sdd_invariant.ssd_size = (coerced_size &
110 ~(((u_int64_t)sd->sd_meta->ssdi_sdd_invariant.ssd_strip_size >>
111 DEV_BSHIFT9) - 1)) * (no_chunk - 1);
112
113 return sr_raid5_init(sd);
114}
115
116int
117sr_raid5_assemble(struct sr_discipline *sd, struct bioc_createraid *bc,
118 int no_chunk, void *data)
119{
120 return sr_raid5_init(sd);
121}
122
123int
124sr_raid5_init(struct sr_discipline *sd)
125{
126 /* Initialise runtime values. */
127 sd->mdssd_dis_specific.mdd_raid5.sr5_strip_bits =
128 sr_validate_stripsize(sd->sd_meta->ssdi_sdd_invariant.ssd_strip_size);
129 if (sd->mdssd_dis_specific.mdd_raid5.sr5_strip_bits == -1) {
130 sr_error(sd->sd_sc, "invalid strip size");
131 return EINVAL22;
132 }
133
134 sd->sd_max_ccb_per_wu = sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no;
135
136 return 0;
137}
138
139int
140sr_raid5_openings(struct sr_discipline *sd)
141{
142 /* Two work units per I/O, two for rebuild/scrub. */
143 return ((sd->sd_max_wu - 2) >> 1);
144}
145
146void
147sr_raid5_set_chunk_state(struct sr_discipline *sd, int c, int new_state)
148{
149 int old_state, s;
150
151 DNPRINTF(SR_D_STATE, "%s: %s: %s: sr_raid_set_chunk_state %d -> %d\n",
152 DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
153 sd->sd_vol.sv_chunks[c]->src_meta.scmi.scm_devname, c, new_state);
154
155 /* ok to go to splbio since this only happens in error path */
156 s = splbio()splraise(0x6);
157 old_state = sd->sd_vol.sv_chunks[c]->src_meta.scm_status;
158
159 /* multiple IOs to the same chunk that fail will come through here */
160 if (old_state == new_state)
161 goto done;
162
163 switch (old_state) {
164 case BIOC_SDONLINE0x00:
165 switch (new_state) {
166 case BIOC_SDOFFLINE0x01:
167 case BIOC_SDSCRUB0x06:
168 break;
169 default:
170 goto die;
171 }
172 break;
173
174 case BIOC_SDOFFLINE0x01:
175 if (new_state == BIOC_SDREBUILD0x03) {
176 ;
177 } else
178 goto die;
179 break;
180
181 case BIOC_SDSCRUB0x06:
182 switch (new_state) {
183 case BIOC_SDONLINE0x00:
184 case BIOC_SDOFFLINE0x01:
185 break;
186 default:
187 goto die;
188 }
189 break;
190
191 case BIOC_SDREBUILD0x03:
192 switch (new_state) {
193 case BIOC_SDONLINE0x00:
194 case BIOC_SDOFFLINE0x01:
195 break;
196 default:
197 goto die;
198 }
199 break;
200
201 default:
202die:
203 splx(s)spllower(s); /* XXX */
204 panic("%s: %s: %s: invalid chunk state transition %d -> %d",
205 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname),
206 sd->sd_meta->ssd_devname,
207 sd->sd_vol.sv_chunks[c]->src_meta.scmi_scm_invariant.scm_devname,
208 old_state, new_state);
209 /* NOTREACHED */
210 }
211
212 sd->sd_vol.sv_chunks[c]->src_meta.scm_status = new_state;
213 sd->sd_set_vol_state(sd);
214
215 sd->sd_must_flush = 1;
216 task_add(systq, &sd->sd_meta_save_task);
217done:
218 splx(s)spllower(s);
219}
220
221void
222sr_raid5_set_vol_state(struct sr_discipline *sd)
223{
224 int states[SR_MAX_STATES7];
225 int new_state, i, s, nd;
226 int old_state = sd->sd_vol_status;
227
228 DNPRINTF(SR_D_STATE, "%s: %s: sr_raid_set_vol_state\n",
229 DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname);
230
231 nd = sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no;
232
233 for (i = 0; i < SR_MAX_STATES7; i++)
234 states[i] = 0;
235
236 for (i = 0; i < nd; i++) {
237 s = sd->sd_vol.sv_chunks[i]->src_meta.scm_status;
238 if (s >= SR_MAX_STATES7)
239 panic("%s: %s: %s: invalid chunk state",
240 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname),
241 sd->sd_meta->ssd_devname,
242 sd->sd_vol.sv_chunks[i]->src_meta.scmi_scm_invariant.scm_devname);
243 states[s]++;
244 }
245
246 if (states[BIOC_SDONLINE0x00] == nd)
247 new_state = BIOC_SVONLINE0x00;
248 else if (states[BIOC_SDONLINE0x00] < nd - 1)
249 new_state = BIOC_SVOFFLINE0x01;
250 else if (states[BIOC_SDSCRUB0x06] != 0)
251 new_state = BIOC_SVSCRUB0x04;
252 else if (states[BIOC_SDREBUILD0x03] != 0)
253 new_state = BIOC_SVREBUILD0x05;
254 else if (states[BIOC_SDONLINE0x00] == nd - 1)
255 new_state = BIOC_SVDEGRADED0x02;
256 else {
257#ifdef SR_DEBUG
258 DNPRINTF(SR_D_STATE, "%s: invalid volume state, old state "
259 "was %d\n", DEVNAME(sd->sd_sc), old_state);
260 for (i = 0; i < nd; i++)
261 DNPRINTF(SR_D_STATE, "%s: chunk %d status = %d\n",
262 DEVNAME(sd->sd_sc), i,
263 sd->sd_vol.sv_chunks[i]->src_meta.scm_status);
264#endif
265 panic("invalid volume state");
266 }
267
268 DNPRINTF(SR_D_STATE, "%s: %s: sr_raid5_set_vol_state %d -> %d\n",
269 DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
270 old_state, new_state);
271
272 switch (old_state) {
273 case BIOC_SVONLINE0x00:
274 switch (new_state) {
275 case BIOC_SVONLINE0x00: /* can go to same state */
276 case BIOC_SVOFFLINE0x01:
277 case BIOC_SVDEGRADED0x02:
278 case BIOC_SVREBUILD0x05: /* happens on boot */
279 break;
280 default:
281 goto die;
282 }
283 break;
284
285 case BIOC_SVOFFLINE0x01:
286 /* XXX this might be a little too much */
287 goto die;
288
289 case BIOC_SVDEGRADED0x02:
290 switch (new_state) {
291 case BIOC_SVOFFLINE0x01:
292 case BIOC_SVREBUILD0x05:
293 case BIOC_SVDEGRADED0x02: /* can go to the same state */
294 break;
295 default:
296 goto die;
297 }
298 break;
299
300 case BIOC_SVBUILDING0x03:
301 switch (new_state) {
302 case BIOC_SVONLINE0x00:
303 case BIOC_SVOFFLINE0x01:
304 case BIOC_SVBUILDING0x03: /* can go to the same state */
305 break;
306 default:
307 goto die;
308 }
309 break;
310
311 case BIOC_SVSCRUB0x04:
312 switch (new_state) {
313 case BIOC_SVONLINE0x00:
314 case BIOC_SVOFFLINE0x01:
315 case BIOC_SVDEGRADED0x02:
316 case BIOC_SVSCRUB0x04: /* can go to same state */
317 break;
318 default:
319 goto die;
320 }
321 break;
322
323 case BIOC_SVREBUILD0x05:
324 switch (new_state) {
325 case BIOC_SVONLINE0x00:
326 case BIOC_SVOFFLINE0x01:
327 case BIOC_SVDEGRADED0x02:
328 case BIOC_SVREBUILD0x05: /* can go to the same state */
329 break;
330 default:
331 goto die;
332 }
333 break;
334
335 default:
336die:
337 panic("%s: %s: invalid volume state transition %d -> %d",
338 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname), sd->sd_meta->ssd_devname,
339 old_state, new_state);
340 /* NOTREACHED */
341 }
342
343 sd->sd_vol_status = new_state;
344}
345
346static inline int
347sr_raid5_chunk_online(struct sr_discipline *sd, int chunk)
348{
349 switch (sd->sd_vol.sv_chunks[chunk]->src_meta.scm_status) {
18
←
Control jumps to 'case 6:' at line 351
→
350 case BIOC_SDONLINE0x00:
351 case BIOC_SDSCRUB0x06:
352 return 1;
19
←
Returning the value 1, which participates in a condition later
→
353 default:
354 return 0;
355 }
356}
357
358static inline int
359sr_raid5_chunk_rebuild(struct sr_discipline *sd, int chunk)
360{
361 switch (sd->sd_vol.sv_chunks[chunk]->src_meta.scm_status) {
362 case BIOC_SDREBUILD0x03:
363 return 1;
364 default:
365 return 0;
366 }
367}
368
369int
370sr_raid5_rw(struct sr_workunit *wu)
371{
372 struct sr_workunit *wu_r = NULL((void *)0);
1
'wu_r' initialized to a null pointer value
→
373 struct sr_discipline *sd = wu->swu_dis;
374 struct scsi_xfer *xs = wu->swu_xs;
375 struct sr_chunk *scp;
376 daddr_t blkno, lba;
377 int64_t chunk_offs, lbaoffs, offset, strip_offs;
378 int64_t strip_bits, strip_no, strip_size;
379 int64_t chunk, no_chunk;
380 int64_t parity, row_size;
381 long length, datalen;
382 void *data;
383 int s;
384
385 /* blkno and scsi error will be handled by sr_validate_io */
386 if (sr_validate_io(wu, &blkno, "sr_raid5_rw"))
2
←
Assuming the condition is false
→
3
←
Taking false branch
→
387 goto bad;
388
389 DNPRINTF(SR_D_DIS, "%s: %s sr_raid5_rw %s: blkno %lld size %d\n",
390 DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
391 (xs->flags & SCSI_DATA_IN) ? "read" : "write",
392 (long long)blkno, xs->datalen);
393
394 strip_size = sd->sd_meta->ssdi_sdd_invariant.ssd_strip_size;
395 strip_bits = sd->mdssd_dis_specific.mdd_raid5.sr5_strip_bits;
396 no_chunk = sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no - 1;
397 row_size = (no_chunk << strip_bits) >> DEV_BSHIFT9;
398
399 data = xs->data;
400 datalen = xs->datalen;
401 lbaoffs = blkno << DEV_BSHIFT9;
402
403 if (xs->flags & SCSI_DATA_OUT0x01000) {
4
←
Assuming the condition is false
→
5
←
Taking false branch
→
404 if ((wu_r = sr_scsi_wu_get(sd, SCSI_NOSLEEP0x00001)) == NULL((void *)0)){
405 printf("%s: %s failed to get read work unit",
406 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname), sd->sd_meta->ssd_devname);
407 goto bad;
408 }
409 wu_r->swu_state = SR_WU_INPROGRESS1;
410 wu_r->swu_flags |= SR_WUF_DISCIPLINE(1<<5);
411 }
412
413 wu->swu_blk_start = 0;
414 while (datalen != 0) {
6
←
Assuming 'datalen' is not equal to 0
→
7
←
Loop condition is true. Entering loop body
→
415 strip_no = lbaoffs >> strip_bits;
416 strip_offs = lbaoffs & (strip_size - 1);
417 chunk_offs = (strip_no / no_chunk) << strip_bits;
418 offset = chunk_offs + strip_offs;
419
420 /* get size remaining in this stripe */
421 length = MIN(strip_size - strip_offs, datalen)(((strip_size - strip_offs)<(datalen))?(strip_size - strip_offs
):(datalen));
8
←
Assuming the condition is false
→
9
←
'?' condition is false
→
422
423 /*
424 * Map disk offset to data and parity chunks, using a left
425 * asymmetric algorithm for the parity assignment.
426 */
427 chunk = strip_no % no_chunk;
428 parity = no_chunk - ((strip_no / no_chunk) % (no_chunk + 1));
429 if (chunk >= parity)
10
←
Assuming 'chunk' is < 'parity'
→
11
←
Taking false branch
→
430 chunk++;
431
432 lba = offset >> DEV_BSHIFT9;
433
434 /* XXX big hammer.. exclude I/O from entire stripe */
435 if (wu->swu_blk_start
11.1
Field 'swu_blk_start' is equal to 0
 == 0)
12
←
Taking true branch
→
436 wu->swu_blk_start = (strip_no / no_chunk) * row_size;
437 wu->swu_blk_end = (strip_no / no_chunk) * row_size +
438 (row_size - 1);
439
440 scp = sd->sd_vol.sv_chunks[chunk];
441 if (xs->flags & SCSI_DATA_IN0x00800) {
13
←
Assuming the condition is false
→
14
←
Taking false branch
→
442 switch (scp->src_meta.scm_status) {
443 case BIOC_SDONLINE0x00:
444 case BIOC_SDSCRUB0x06:
445 /*
446 * Chunk is online, issue a single read
447 * request.
448 */
449 if (sr_raid5_addio(wu, chunk, lba, length,
450 data, xs->flags, 0, NULL((void *)0)))
451 goto bad;
452 break;
453 case BIOC_SDOFFLINE0x01:
454 case BIOC_SDREBUILD0x03:
455 case BIOC_SDHOTSPARE0x04:
456 if (sr_raid5_regenerate(wu, chunk, lba,
457 length, data))
458 goto bad;
459 break;
460 default:
461 printf("%s: is offline, can't read\n",
462 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname));
463 goto bad;
464 }
465 } else {
466 if (sr_raid5_write(wu, wu_r, chunk, parity, lba,
15
←
Passing null pointer value via 2nd parameter 'wu_r'
→
16
←
Calling 'sr_raid5_write'
→
467 length, data, xs->flags, 0))
468 goto bad;
469 }
470
471 /* advance to next block */
472 lbaoffs += length;
473 datalen -= length;
474 data += length;
475 }
476
477 s = splbio()splraise(0x6);
478 if (wu_r) {
479 if (wu_r->swu_io_count > 0) {
480 /* collide write request with reads */
481 wu_r->swu_blk_start = wu->swu_blk_start;
482 wu_r->swu_blk_end = wu->swu_blk_end;
483
484 wu->swu_state = SR_WU_DEFERRED5;
485 wu_r->swu_collider = wu;
486 TAILQ_INSERT_TAIL(&sd->sd_wu_defq, wu, swu_link)do { (wu)->swu_link.tqe_next = ((void *)0); (wu)->swu_link
.tqe_prev = (&sd->sd_wu_defq)->tqh_last; *(&sd->
sd_wu_defq)->tqh_last = (wu); (&sd->sd_wu_defq)->
tqh_last = &(wu)->swu_link.tqe_next; } while (0);
487
488 wu = wu_r;
489 } else {
490 sr_scsi_wu_put(sd, wu_r);
491 }
492 }
493 splx(s)spllower(s);
494
495 sr_schedule_wu(wu);
496
497 return (0);
498
499bad:
500 /* wu is unwound by sr_wu_put */
501 if (wu_r)
502 sr_scsi_wu_put(sd, wu_r);
503 return (1);
504}
505
506int
507sr_raid5_regenerate(struct sr_workunit *wu, int chunk, daddr_t blkno,
508 long len, void *data)
509{
510 struct sr_discipline *sd = wu->swu_dis;
511 int i;
512
513 /*
514 * Regenerate a block on a RAID 5 volume by xoring the data and parity
515 * from all of the remaining online chunks. This requires the parity
516 * to already be correct.
517 */
518
519 DNPRINTF(SR_D_DIS, "%s: %s sr_raid5_regenerate chunk %d offline, "
520 "regenerating block %llu\n",
521 DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname, chunk, blkno);
522
523 memset(data, 0, len)__builtin_memset((data), (0), (len));
524 for (i = 0; i < sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no; i++) {
525 if (i == chunk)
526 continue;
527 if (!sr_raid5_chunk_online(sd, i))
528 goto bad;
529 if (sr_raid5_addio(wu, i, blkno, len, NULL((void *)0), SCSI_DATA_IN0x00800,
530 0, data))
531 goto bad;
532 }
533 return (0);
534
535bad:
536 return (1);
537}
538
539int
540sr_raid5_write(struct sr_workunit *wu, struct sr_workunit *wu_r, int chunk,
541 int parity, daddr_t blkno, long len, void *data, int xsflags,
542 int ccbflags)
543{
544 struct sr_discipline *sd = wu->swu_dis;
545 struct scsi_xfer *xs = wu->swu_xs;
546 void *xorbuf;
547 int chunk_online, chunk_rebuild;
548 int parity_online, parity_rebuild;
549 int other_offline = 0, other_rebuild = 0;
550 int i;
551
552 /*
553 * Perform a write to a RAID 5 volume. This write routine does not
554 * require the parity to already be correct and will operate on a
555 * uninitialised volume.
556 *
557 * There are four possible cases:
558 *
559 * 1) All data chunks and parity are online. In this case we read the
560 * data from all data chunks, except the one we are writing to, in
561 * order to calculate and write the new parity.
562 *
563 * 2) The parity chunk is offline. In this case we only need to write
564 * to the data chunk. No parity calculation is required.
565 *
566 * 3) The data chunk is offline. In this case we read the data from all
567 * online chunks in order to calculate and write the new parity.
568 * This is the same as (1) except we do not write the data chunk.
569 *
570 * 4) A different data chunk is offline. The new parity is calculated
571 * by taking the existing parity, xoring the original data and
572 * xoring in the new data. This requires that the parity already be
573 * correct, which it will be if any of the data chunks has
574 * previously been written.
575 *
576 * There is an additional complication introduced by a chunk that is
577 * being rebuilt. If this is the data or parity chunk, then we want
578 * to write to it as per normal. If it is another data chunk then we
579 * need to presume that it has not yet been regenerated and use the
580 * same method as detailed in (4) above.
581 */
582
583 DNPRINTF(SR_D_DIS, "%s: %s sr_raid5_write chunk %i parity %i "
584 "blkno %llu\n", DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
585 chunk, parity, (unsigned long long)blkno);
586
587 chunk_online = sr_raid5_chunk_online(sd, chunk);
588 chunk_rebuild = sr_raid5_chunk_rebuild(sd, chunk);
589 parity_online = sr_raid5_chunk_online(sd, parity);
17
←
Calling 'sr_raid5_chunk_online'
→
20
←
Returning from 'sr_raid5_chunk_online'
→
590 parity_rebuild = sr_raid5_chunk_rebuild(sd, parity);
591
592 for (i = 0; i < sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no; i++) {
21
←
Assuming 'i' is >= field 'ssd_chunk_no'
→
22
←
Loop condition is false. Execution continues on line 605
→
593 if (i == chunk || i == parity)
594 continue;
595 if (sr_raid5_chunk_rebuild(sd, i))
596 other_rebuild = 1;
597 else if (!sr_raid5_chunk_online(sd, i))
598 other_offline = 1;
599 }
600
601 DNPRINTF(SR_D_DIS, "%s: %s chunk online %d, parity online %d, "
602 "other offline %d\n", DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
603 chunk_online, parity_online, other_offline);
604
605 if (!parity_online
22.1
'parity_online' is 1
 && !parity_rebuild)
606 goto data_write;
607
608 xorbuf = sr_block_get(sd, len);
609 if (xorbuf == NULL((void *)0))
23
←
Assuming 'xorbuf' is not equal to NULL
→
24
←
Taking false branch
→
610 goto bad;
611 memcpy(xorbuf, data, len)__builtin_memcpy((xorbuf), (data), (len));
612
613 if (other_offline
24.1
'other_offline' is 0
 || other_rebuild
24.2
'other_rebuild' is 0
) {
25
←
Taking false branch
→
614
615 /*
616 * XXX - If we can guarantee that this LBA has been scrubbed
617 * then we can also take this faster path.
618 */
619
620 /* Read in existing data and existing parity. */
621 if (sr_raid5_addio(wu_r, chunk, blkno, len, NULL((void *)0),
622 SCSI_DATA_IN0x00800, 0, xorbuf))
623 goto bad;
624 if (sr_raid5_addio(wu_r, parity, blkno, len, NULL((void *)0),
625 SCSI_DATA_IN0x00800, 0, xorbuf))
626 goto bad;
627
628 } else {
629
630 /* Read in existing data from all other chunks. */
631 for (i = 0; i < sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no; i++) {
26
←
Assuming 'i' is < field 'ssd_chunk_no'
→
27
←
Loop condition is true. Entering loop body
→
632 if (i == chunk || i == parity)
28
←
Assuming 'i' is not equal to 'chunk'
→
29
←
Assuming 'i' is not equal to 'parity'
→
30
←
Taking false branch
→
633 continue;
634 if (sr_raid5_addio(wu_r, i, blkno, len, NULL((void *)0),
31
←
Passing null pointer value via 1st parameter 'wu'
→
32
←
Calling 'sr_raid5_addio'
→
635 SCSI_DATA_IN0x00800, 0, xorbuf))
636 goto bad;
637 }
638
639 }
640
641 /* Write new parity. */
642 if (sr_raid5_addio(wu, parity, blkno, len, xorbuf, xs->flags,
643 SR_CCBF_FREEBUF(1<<0), NULL((void *)0)))
644 goto bad;
645
646data_write:
647 /* Write new data. */
648 if (chunk_online || chunk_rebuild)
649 if (sr_raid5_addio(wu, chunk, blkno, len, data, xs->flags,
650 0, NULL((void *)0)))
651 goto bad;
652
653 return (0);
654
655bad:
656 return (1);
657}
658
659void
660sr_raid5_intr(struct buf *bp)
661{
662 struct sr_ccb *ccb = (struct sr_ccb *)bp;
663 struct sr_workunit *wu = ccb->ccb_wu;
664 struct sr_discipline *sd = wu->swu_dis;
665 int s;
666
667 DNPRINTF(SR_D_INTR, "%s: sr_raid5_intr bp %p xs %p\n",
668 DEVNAME(sd->sd_sc), bp, wu->swu_xs);
669
670 s = splbio()splraise(0x6);
671 sr_ccb_done(ccb);
672
673 /* XXX - Should this be done via the taskq? */
674
675 /* XOR data to result. */
676 if (ccb->ccb_state == SR_CCB_OK2 && ccb->ccb_opaque)
677 sr_raid5_xor(ccb->ccb_opaque, ccb->ccb_buf.b_data,
678 ccb->ccb_buf.b_bcount);
679
680 /* Free allocated data buffer. */
681 if (ccb->ccb_flags & SR_CCBF_FREEBUF(1<<0)) {
682 sr_block_put(sd, ccb->ccb_buf.b_data, ccb->ccb_buf.b_bcount);
683 ccb->ccb_buf.b_data = NULL((void *)0);
684 }
685
686 sr_wu_done(wu);
687 splx(s)spllower(s);
688}
689
690int
691sr_raid5_wu_done(struct sr_workunit *wu)
692{
693 struct sr_discipline *sd = wu->swu_dis;
694 struct scsi_xfer *xs = wu->swu_xs;
695
696 /* XXX - we have no way of propagating errors... */
697 if (wu->swu_flags & (SR_WUF_DISCIPLINE(1<<5) | SR_WUF_REBUILD(1<<0)))
698 return SR_WU_OK2;
699
700 /* XXX - This is insufficient for RAID 5. */
701 if (wu->swu_ios_succeeded > 0) {
702 xs->error = XS_NOERROR0;
703 return SR_WU_OK2;
704 }
705
706 if (xs->flags & SCSI_DATA_IN0x00800) {
707 printf("%s: retrying read on block %lld\n",
708 sd->sd_meta->ssd_devname, (long long)wu->swu_blk_start);
709 sr_wu_release_ccbs(wu);
710 wu->swu_state = SR_WU_RESTART7;
711 if (sd->sd_scsi_rw(wu) == 0)
712 return SR_WU_RESTART7;
713 } else {
714 /* XXX - retry write if we just went from online to degraded. */
715 printf("%s: permanently fail write on block %lld\n",
716 sd->sd_meta->ssd_devname, (long long)wu->swu_blk_start);
717 }
718
719 wu->swu_state = SR_WU_FAILED3;
720 xs->error = XS_DRIVER_STUFFUP2;
721
722 return SR_WU_FAILED3;
723}
724
725int
726sr_raid5_addio(struct sr_workunit *wu, int chunk, daddr_t blkno,
727 long len, void *data, int xsflags, int ccbflags, void *xorbuf)
728{
729 struct sr_discipline *sd = wu->swu_dis;
33
←
Access to field 'swu_dis' results in a dereference of a null pointer (loaded from variable 'wu')
730 struct sr_ccb *ccb;
731
732 DNPRINTF(SR_D_DIS, "sr_raid5_addio: %s chunk %d block %lld "
733 "length %ld %s\n", (xsflags & SCSI_DATA_IN) ? "read" : "write",
734 chunk, (long long)blkno, len, xorbuf ? "X0R" : "-");
735
736 /* Allocate temporary buffer. */
737 if (data == NULL((void *)0)) {
738 data = sr_block_get(sd, len);
739 if (data == NULL((void *)0))
740 return (-1);
741 ccbflags |= SR_CCBF_FREEBUF(1<<0);
742 }
743
744 ccb = sr_ccb_rw(sd, chunk, blkno, len, data, xsflags, ccbflags);
745 if (ccb == NULL((void *)0)) {
746 if (ccbflags & SR_CCBF_FREEBUF(1<<0))
747 sr_block_put(sd, data, len);
748 return (-1);
749 }
750 ccb->ccb_opaque = xorbuf;
751 sr_wu_enqueue_ccb(wu, ccb);
752
753 return (0);
754}
755
756void
757sr_raid5_xor(void *a, void *b, int len)
758{
759 uint32_t *xa = a, *xb = b;
760
761 len >>= 2;
762 while (len--)
763 *xa++ ^= *xb++;
764}
765
766void
767sr_raid5_rebuild(struct sr_discipline *sd)
768{
769 int64_t strip_no, strip_size, strip_bits, i, restart;
770 int64_t chunk_count, chunk_strips, chunk_lba, chunk_size, row_size;
771 struct sr_workunit *wu_r, *wu_w;
772 int s, slept, percent = 0, old_percent = -1;
773 int rebuild_chunk = -1;
774 void *xorbuf;
775
776 /* Find the rebuild chunk. */
777 for (i = 0; i < sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no; i++) {
778 if (sr_raid5_chunk_rebuild(sd, i)) {
779 rebuild_chunk = i;
780 break;
781 }
782 }
783 if (rebuild_chunk == -1)
784 goto bad;
785
786 strip_size = sd->sd_meta->ssdi_sdd_invariant.ssd_strip_size;
787 strip_bits = sd->mdssd_dis_specific.mdd_raid5.sr5_strip_bits;
788 chunk_count = sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no - 1;
789 chunk_size = sd->sd_meta->ssdi_sdd_invariant.ssd_size / chunk_count;
790 chunk_strips = (chunk_size << DEV_BSHIFT9) >> strip_bits;
791 row_size = (chunk_count << strip_bits) >> DEV_BSHIFT9;
792
793 DNPRINTF(SR_D_REBUILD, "%s: %s sr_raid5_rebuild volume size = %lld, "
794 "chunk count = %lld, chunk size = %lld, chunk strips = %lld, "
795 "row size = %lld\n", DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
796 sd->sd_meta->ssdi.ssd_size, chunk_count, chunk_size, chunk_strips,
797 row_size);
798
799 restart = sd->sd_meta->ssd_rebuild / row_size;
800 if (restart > chunk_strips) {
801 printf("%s: bogus rebuild restart offset, starting from 0\n",
802 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname));
803 restart = 0;
804 }
805 if (restart != 0) {
806 percent = sr_rebuild_percent(sd);
807 printf("%s: resuming rebuild on %s at %d%%\n",
808 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname), sd->sd_meta->ssd_devname, percent);
809 }
810
811 for (strip_no = restart; strip_no < chunk_strips; strip_no++) {
812 chunk_lba = (strip_size >> DEV_BSHIFT9) * strip_no;
813
814 DNPRINTF(SR_D_REBUILD, "%s: %s rebuild strip %lld, "
815 "chunk lba = %lld\n", DEVNAME(sd->sd_sc),
816 sd->sd_meta->ssd_devname, strip_no, chunk_lba);
817
818 wu_w = sr_scsi_wu_get(sd, 0);
819 wu_r = sr_scsi_wu_get(sd, 0);
820
821 xorbuf = sr_block_get(sd, strip_size);
822 if (xorbuf == NULL((void *)0))
823 goto bad;
824 if (sr_raid5_regenerate(wu_r, rebuild_chunk, chunk_lba,
825 strip_size, xorbuf))
826 goto bad;
827 if (sr_raid5_addio(wu_w, rebuild_chunk, chunk_lba, strip_size,
828 xorbuf, SCSI_DATA_OUT0x01000, SR_CCBF_FREEBUF(1<<0), NULL((void *)0)))
829 goto bad;
830
831 /* Collide write work unit with read work unit. */
832 wu_r->swu_state = SR_WU_INPROGRESS1;
833 wu_r->swu_flags |= SR_WUF_REBUILD(1<<0);
834 wu_w->swu_state = SR_WU_DEFERRED5;
835 wu_w->swu_flags |= SR_WUF_REBUILD(1<<0) | SR_WUF_WAKEUP(1<<4);
836 wu_r->swu_collider = wu_w;
837
838 /* Block I/O to this strip while we rebuild it. */
839 wu_r->swu_blk_start = (strip_no / chunk_count) * row_size;
840 wu_r->swu_blk_end = wu_r->swu_blk_start + row_size - 1;
841 wu_w->swu_blk_start = wu_r->swu_blk_start;
842 wu_w->swu_blk_end = wu_r->swu_blk_end;
843
844 DNPRINTF(SR_D_REBUILD, "%s: %s rebuild swu_blk_start = %lld, "
845 "swu_blk_end = %lld\n", DEVNAME(sd->sd_sc),
846 sd->sd_meta->ssd_devname,
847 wu_r->swu_blk_start, wu_r->swu_blk_end);
848
849 s = splbio()splraise(0x6);
850 TAILQ_INSERT_TAIL(&sd->sd_wu_defq, wu_w, swu_link)do { (wu_w)->swu_link.tqe_next = ((void *)0); (wu_w)->swu_link
.tqe_prev = (&sd->sd_wu_defq)->tqh_last; *(&sd->
sd_wu_defq)->tqh_last = (wu_w); (&sd->sd_wu_defq)->
tqh_last = &(wu_w)->swu_link.tqe_next; } while (0);
851 splx(s)spllower(s);
852
853 sr_schedule_wu(wu_r);
854
855 slept = 0;
856 while ((wu_w->swu_flags & SR_WUF_REBUILDIOCOMP(1<<1)) == 0) {
857 tsleep_nsec(wu_w, PRIBIO16, "sr_rebuild", INFSLP0xffffffffffffffffULL);
858 slept = 1;
859 }
860 if (!slept) {
861 tsleep_nsec(sd->sd_sc, PWAIT32, "sr_yield",
862 MSEC_TO_NSEC(1));
863 }
864
865 sr_scsi_wu_put(sd, wu_r);
866 sr_scsi_wu_put(sd, wu_w);
867
868 sd->sd_meta->ssd_rebuild = chunk_lba * chunk_count;
869
870 percent = sr_rebuild_percent(sd);
871 if (percent != old_percent && strip_no != chunk_strips - 1) {
872 if (sr_meta_save(sd, SR_META_DIRTY0x1))
873 printf("%s: could not save metadata to %s\n",
874 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname),
875 sd->sd_meta->ssd_devname);
876 old_percent = percent;
877 }
878
879 if (sd->sd_reb_abort)
880 goto abort;
881 }
882
883 DNPRINTF(SR_D_REBUILD, "%s: %s rebuild complete\n", DEVNAME(sd->sd_sc),
884 sd->sd_meta->ssd_devname);
885
886 /* all done */
887 sd->sd_meta->ssd_rebuild = 0;
888 for (i = 0; i < sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no; i++) {
889 if (sd->sd_vol.sv_chunks[i]->src_meta.scm_status ==
890 BIOC_SDREBUILD0x03) {
891 sd->sd_set_chunk_state(sd, i, BIOC_SDONLINE0x00);
892 break;
893 }
894 }
895
896 return;
897
898abort:
899 if (sr_meta_save(sd, SR_META_DIRTY0x1))
900 printf("%s: could not save metadata to %s\n",
901 DEVNAME(sd->sd_sc)((sd->sd_sc)->sc_dev.dv_xname), sd->sd_meta->ssd_devname);
902bad:
903 return;
904}
905
906#if 0
907void
908sr_raid5_scrub(struct sr_discipline *sd)
909{
910 int64_t strip_no, strip_size, no_chunk, parity, max_strip, strip_bits;
911 int64_t i;
912 struct sr_workunit *wu_r, *wu_w;
913 int s, slept;
914 void *xorbuf;
915
916 wu_w = sr_scsi_wu_get(sd, 0);
917 wu_r = sr_scsi_wu_get(sd, 0);
918
919 no_chunk = sd->sd_meta->ssdi_sdd_invariant.ssd_chunk_no - 1;
920 strip_size = sd->sd_meta->ssdi_sdd_invariant.ssd_strip_size;
921 strip_bits = sd->mdssd_dis_specific.mdd_raid5.sr5_strip_bits;
922 max_strip = sd->sd_meta->ssdi_sdd_invariant.ssd_size >> strip_bits;
923
924 for (strip_no = 0; strip_no < max_strip; strip_no++) {
925 parity = no_chunk - ((strip_no / no_chunk) % (no_chunk + 1));
926
927 xorbuf = sr_block_get(sd, strip_size);
928 for (i = 0; i <= no_chunk; i++) {
929 if (i != parity)
930 sr_raid5_addio(wu_r, i, 0xBADCAFE, strip_size,
931 NULL((void *)0), SCSI_DATA_IN0x00800, 0, xorbuf);
932 }
933 sr_raid5_addio(wu_w, parity, 0xBADCAFE, strip_size, xorbuf,
934 SCSI_DATA_OUT0x01000, SR_CCBF_FREEBUF(1<<0), NULL((void *)0));
935
936 wu_r->swu_flags |= SR_WUF_REBUILD(1<<0);
937
938 /* Collide wu_w with wu_r */
939 wu_w->swu_state = SR_WU_DEFERRED5;
940 wu_w->swu_flags |= SR_WUF_REBUILD(1<<0) | SR_WUF_WAKEUP(1<<4);
941 wu_r->swu_collider = wu_w;
942
943 s = splbio()splraise(0x6);
944 TAILQ_INSERT_TAIL(&sd->sd_wu_defq, wu_w, swu_link)do { (wu_w)->swu_link.tqe_next = ((void *)0); (wu_w)->swu_link
.tqe_prev = (&sd->sd_wu_defq)->tqh_last; *(&sd->
sd_wu_defq)->tqh_last = (wu_w); (&sd->sd_wu_defq)->
tqh_last = &(wu_w)->swu_link.tqe_next; } while (0);
945 splx(s)spllower(s);
946
947 wu_r->swu_state = SR_WU_INPROGRESS1;
948 sr_schedule_wu(wu_r);
949
950 slept = 0;
951 while ((wu_w->swu_flags & SR_WUF_REBUILDIOCOMP(1<<1)) == 0) {
952 tsleep_nsec(wu_w, PRIBIO16, "sr_scrub", INFSLP0xffffffffffffffffULL);
953 slept = 1;
954 }
955 if (!slept) {
956 tsleep_nsec(sd->sd_sc, PWAIT32, "sr_yield",
957 MSEC_TO_NSEC(1));
958 }
959 }
960}
961#endif