1/*-
2 * Copyright (c) 2000-2003 Tor Egge
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
| 1/*-
2 * Copyright (c) 2000-2003 Tor Egge
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
|
28__FBSDID("$FreeBSD: head/sys/ufs/ffs/ffs_rawread.c 233438 2012-03-25 00:02:37Z mckusick $");
| 28__FBSDID("$FreeBSD: head/sys/ufs/ffs/ffs_rawread.c 248084 2013-03-09 02:32:23Z attilio $");
|
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/fcntl.h>
33#include <sys/file.h>
34#include <sys/stat.h>
35#include <sys/proc.h>
36#include <sys/limits.h>
37#include <sys/mount.h>
38#include <sys/namei.h>
39#include <sys/vnode.h>
40#include <sys/conf.h>
41#include <sys/filio.h>
42#include <sys/ttycom.h>
43#include <sys/bio.h>
44#include <sys/buf.h>
| 29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/fcntl.h>
33#include <sys/file.h>
34#include <sys/stat.h>
35#include <sys/proc.h>
36#include <sys/limits.h>
37#include <sys/mount.h>
38#include <sys/namei.h>
39#include <sys/vnode.h>
40#include <sys/conf.h>
41#include <sys/filio.h>
42#include <sys/ttycom.h>
43#include <sys/bio.h>
44#include <sys/buf.h>
|
| 45#include <sys/rwlock.h>
|
45#include <ufs/ufs/extattr.h>
46#include <ufs/ufs/quota.h>
47#include <ufs/ufs/inode.h>
48#include <ufs/ufs/ufsmount.h>
49#include <ufs/ufs/ufs_extern.h>
50#include <ufs/ffs/fs.h>
51#include <ufs/ffs/ffs_extern.h>
52
53#include <vm/vm.h>
54#include <vm/vm_extern.h>
55#include <vm/vm_object.h>
56#include <sys/kernel.h>
57#include <sys/sysctl.h>
58
59static int ffs_rawread_readahead(struct vnode *vp,
60 caddr_t udata,
61 off_t offset,
62 size_t len,
63 struct thread *td,
64 struct buf *bp,
65 caddr_t sa);
66static int ffs_rawread_main(struct vnode *vp,
67 struct uio *uio);
68
69static int ffs_rawread_sync(struct vnode *vp);
70
71int ffs_rawread(struct vnode *vp, struct uio *uio, int *workdone);
72
73void ffs_rawread_setup(void);
74
75SYSCTL_DECL(_vfs_ffs);
76
77static int ffsrawbufcnt = 4;
78SYSCTL_INT(_vfs_ffs, OID_AUTO, ffsrawbufcnt, CTLFLAG_RD, &ffsrawbufcnt, 0,
79 "Buffers available for raw reads");
80
81static int allowrawread = 1;
82SYSCTL_INT(_vfs_ffs, OID_AUTO, allowrawread, CTLFLAG_RW, &allowrawread, 0,
83 "Flag to enable raw reads");
84
85static int rawreadahead = 1;
86SYSCTL_INT(_vfs_ffs, OID_AUTO, rawreadahead, CTLFLAG_RW, &rawreadahead, 0,
87 "Flag to enable readahead for long raw reads");
88
89
90void
91ffs_rawread_setup(void)
92{
93 ffsrawbufcnt = (nswbuf > 100 ) ? (nswbuf - (nswbuf >> 4)) : nswbuf - 8;
94}
95
96
97static int
98ffs_rawread_sync(struct vnode *vp)
99{
100 int error;
101 int upgraded;
102 struct bufobj *bo;
103 struct mount *mp;
104 vm_object_t obj;
105
106 /* Check for dirty mmap, pending writes and dirty buffers */
107 bo = &vp->v_bufobj;
108 BO_LOCK(bo);
109 VI_LOCK(vp);
110 if (bo->bo_numoutput > 0 ||
111 bo->bo_dirty.bv_cnt > 0 ||
112 ((obj = vp->v_object) != NULL &&
113 (obj->flags & OBJ_MIGHTBEDIRTY) != 0)) {
114 VI_UNLOCK(vp);
115 BO_UNLOCK(bo);
116
117 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
118 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
119 upgraded = 1;
120 else
121 upgraded = 0;
122 VOP_UNLOCK(vp, 0);
123 (void) vn_start_write(vp, &mp, V_WAIT);
124 VOP_LOCK(vp, LK_EXCLUSIVE);
125 } else if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
126 upgraded = 1;
127 /* Upgrade to exclusive lock, this might block */
128 VOP_LOCK(vp, LK_UPGRADE);
129 } else
130 upgraded = 0;
131
132
133 VI_LOCK(vp);
134 /* Check if vnode was reclaimed while unlocked. */
135 if ((vp->v_iflag & VI_DOOMED) != 0) {
136 VI_UNLOCK(vp);
137 if (upgraded != 0)
138 VOP_LOCK(vp, LK_DOWNGRADE);
139 vn_finished_write(mp);
140 return (EIO);
141 }
142 /* Attempt to msync mmap() regions to clean dirty mmap */
143 if ((obj = vp->v_object) != NULL &&
144 (obj->flags & OBJ_MIGHTBEDIRTY) != 0) {
145 VI_UNLOCK(vp);
| 46#include <ufs/ufs/extattr.h>
47#include <ufs/ufs/quota.h>
48#include <ufs/ufs/inode.h>
49#include <ufs/ufs/ufsmount.h>
50#include <ufs/ufs/ufs_extern.h>
51#include <ufs/ffs/fs.h>
52#include <ufs/ffs/ffs_extern.h>
53
54#include <vm/vm.h>
55#include <vm/vm_extern.h>
56#include <vm/vm_object.h>
57#include <sys/kernel.h>
58#include <sys/sysctl.h>
59
60static int ffs_rawread_readahead(struct vnode *vp,
61 caddr_t udata,
62 off_t offset,
63 size_t len,
64 struct thread *td,
65 struct buf *bp,
66 caddr_t sa);
67static int ffs_rawread_main(struct vnode *vp,
68 struct uio *uio);
69
70static int ffs_rawread_sync(struct vnode *vp);
71
72int ffs_rawread(struct vnode *vp, struct uio *uio, int *workdone);
73
74void ffs_rawread_setup(void);
75
76SYSCTL_DECL(_vfs_ffs);
77
78static int ffsrawbufcnt = 4;
79SYSCTL_INT(_vfs_ffs, OID_AUTO, ffsrawbufcnt, CTLFLAG_RD, &ffsrawbufcnt, 0,
80 "Buffers available for raw reads");
81
82static int allowrawread = 1;
83SYSCTL_INT(_vfs_ffs, OID_AUTO, allowrawread, CTLFLAG_RW, &allowrawread, 0,
84 "Flag to enable raw reads");
85
86static int rawreadahead = 1;
87SYSCTL_INT(_vfs_ffs, OID_AUTO, rawreadahead, CTLFLAG_RW, &rawreadahead, 0,
88 "Flag to enable readahead for long raw reads");
89
90
91void
92ffs_rawread_setup(void)
93{
94 ffsrawbufcnt = (nswbuf > 100 ) ? (nswbuf - (nswbuf >> 4)) : nswbuf - 8;
95}
96
97
98static int
99ffs_rawread_sync(struct vnode *vp)
100{
101 int error;
102 int upgraded;
103 struct bufobj *bo;
104 struct mount *mp;
105 vm_object_t obj;
106
107 /* Check for dirty mmap, pending writes and dirty buffers */
108 bo = &vp->v_bufobj;
109 BO_LOCK(bo);
110 VI_LOCK(vp);
111 if (bo->bo_numoutput > 0 ||
112 bo->bo_dirty.bv_cnt > 0 ||
113 ((obj = vp->v_object) != NULL &&
114 (obj->flags & OBJ_MIGHTBEDIRTY) != 0)) {
115 VI_UNLOCK(vp);
116 BO_UNLOCK(bo);
117
118 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
119 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
120 upgraded = 1;
121 else
122 upgraded = 0;
123 VOP_UNLOCK(vp, 0);
124 (void) vn_start_write(vp, &mp, V_WAIT);
125 VOP_LOCK(vp, LK_EXCLUSIVE);
126 } else if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
127 upgraded = 1;
128 /* Upgrade to exclusive lock, this might block */
129 VOP_LOCK(vp, LK_UPGRADE);
130 } else
131 upgraded = 0;
132
133
134 VI_LOCK(vp);
135 /* Check if vnode was reclaimed while unlocked. */
136 if ((vp->v_iflag & VI_DOOMED) != 0) {
137 VI_UNLOCK(vp);
138 if (upgraded != 0)
139 VOP_LOCK(vp, LK_DOWNGRADE);
140 vn_finished_write(mp);
141 return (EIO);
142 }
143 /* Attempt to msync mmap() regions to clean dirty mmap */
144 if ((obj = vp->v_object) != NULL &&
145 (obj->flags & OBJ_MIGHTBEDIRTY) != 0) {
146 VI_UNLOCK(vp);
|
146 VM_OBJECT_LOCK(obj);
| 147 VM_OBJECT_WLOCK(obj);
|
147 vm_object_page_clean(obj, 0, 0, OBJPC_SYNC);
| 148 vm_object_page_clean(obj, 0, 0, OBJPC_SYNC);
|
148 VM_OBJECT_UNLOCK(obj);
| 149 VM_OBJECT_WUNLOCK(obj);
|
149 } else
150 VI_UNLOCK(vp);
151
152 /* Wait for pending writes to complete */
153 BO_LOCK(bo);
154 error = bufobj_wwait(&vp->v_bufobj, 0, 0);
155 if (error != 0) {
156 /* XXX: can't happen with a zero timeout ??? */
157 BO_UNLOCK(bo);
158 if (upgraded != 0)
159 VOP_LOCK(vp, LK_DOWNGRADE);
160 vn_finished_write(mp);
161 return (error);
162 }
163 /* Flush dirty buffers */
164 if (bo->bo_dirty.bv_cnt > 0) {
165 BO_UNLOCK(bo);
166 if ((error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0) {
167 if (upgraded != 0)
168 VOP_LOCK(vp, LK_DOWNGRADE);
169 vn_finished_write(mp);
170 return (error);
171 }
172 BO_LOCK(bo);
173 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
174 panic("ffs_rawread_sync: dirty bufs");
175 }
176 BO_UNLOCK(bo);
177 if (upgraded != 0)
178 VOP_LOCK(vp, LK_DOWNGRADE);
179 vn_finished_write(mp);
180 } else {
181 VI_UNLOCK(vp);
182 BO_UNLOCK(bo);
183 }
184 return 0;
185}
186
187
188static int
189ffs_rawread_readahead(struct vnode *vp,
190 caddr_t udata,
191 off_t offset,
192 size_t len,
193 struct thread *td,
194 struct buf *bp,
195 caddr_t sa)
196{
197 int error;
198 u_int iolen;
199 off_t blockno;
200 int blockoff;
201 int bsize;
202 struct vnode *dp;
203 int bforwards;
204 struct inode *ip;
205 ufs2_daddr_t blkno;
206
207 bsize = vp->v_mount->mnt_stat.f_iosize;
208
209 ip = VTOI(vp);
210 dp = ip->i_devvp;
211
212 iolen = ((vm_offset_t) udata) & PAGE_MASK;
213 bp->b_bcount = len;
214 if (bp->b_bcount + iolen > bp->b_kvasize) {
215 bp->b_bcount = bp->b_kvasize;
216 if (iolen != 0)
217 bp->b_bcount -= PAGE_SIZE;
218 }
219 bp->b_flags = 0; /* XXX necessary ? */
220 bp->b_iocmd = BIO_READ;
221 bp->b_iodone = bdone;
222 bp->b_data = udata;
223 bp->b_saveaddr = sa;
224 blockno = offset / bsize;
225 blockoff = (offset % bsize) / DEV_BSIZE;
226 if ((daddr_t) blockno != blockno) {
227 return EINVAL; /* blockno overflow */
228 }
229
230 bp->b_lblkno = bp->b_blkno = blockno;
231
232 error = ufs_bmaparray(vp, bp->b_lblkno, &blkno, NULL, &bforwards, NULL);
233 if (error != 0)
234 return error;
235 if (blkno == -1) {
236
237 /* Fill holes with NULs to preserve semantics */
238
239 if (bp->b_bcount + blockoff * DEV_BSIZE > bsize)
240 bp->b_bcount = bsize - blockoff * DEV_BSIZE;
241 bp->b_bufsize = bp->b_bcount;
242
243 if (vmapbuf(bp) < 0)
244 return EFAULT;
245
246 maybe_yield();
247 bzero(bp->b_data, bp->b_bufsize);
248
249 /* Mark operation completed (similar to bufdone()) */
250
251 bp->b_resid = 0;
252 bp->b_flags |= B_DONE;
253 return 0;
254 }
255 bp->b_blkno = blkno + blockoff;
256 bp->b_offset = bp->b_iooffset = (blkno + blockoff) * DEV_BSIZE;
257
258 if (bp->b_bcount + blockoff * DEV_BSIZE > bsize * (1 + bforwards))
259 bp->b_bcount = bsize * (1 + bforwards) - blockoff * DEV_BSIZE;
260 bp->b_bufsize = bp->b_bcount;
261
262 if (vmapbuf(bp) < 0)
263 return EFAULT;
264
265 BO_STRATEGY(&dp->v_bufobj, bp);
266 return 0;
267}
268
269
270static int
271ffs_rawread_main(struct vnode *vp,
272 struct uio *uio)
273{
274 int error, nerror;
275 struct buf *bp, *nbp, *tbp;
276 caddr_t sa, nsa, tsa;
277 u_int iolen;
278 int spl;
279 caddr_t udata;
280 long resid;
281 off_t offset;
282 struct thread *td;
283
284 td = uio->uio_td ? uio->uio_td : curthread;
285 udata = uio->uio_iov->iov_base;
286 resid = uio->uio_resid;
287 offset = uio->uio_offset;
288
289 /*
290 * keep the process from being swapped
291 */
292 PHOLD(td->td_proc);
293
294 error = 0;
295 nerror = 0;
296
297 bp = NULL;
298 nbp = NULL;
299 sa = NULL;
300 nsa = NULL;
301
302 while (resid > 0) {
303
304 if (bp == NULL) { /* Setup first read */
305 /* XXX: Leave some bufs for swap */
306 bp = getpbuf(&ffsrawbufcnt);
307 sa = bp->b_data;
308 pbgetvp(vp, bp);
309 error = ffs_rawread_readahead(vp, udata, offset,
310 resid, td, bp, sa);
311 if (error != 0)
312 break;
313
314 if (resid > bp->b_bufsize) { /* Setup fist readahead */
315 /* XXX: Leave bufs for swap */
316 if (rawreadahead != 0)
317 nbp = trypbuf(&ffsrawbufcnt);
318 else
319 nbp = NULL;
320 if (nbp != NULL) {
321 nsa = nbp->b_data;
322 pbgetvp(vp, nbp);
323
324 nerror = ffs_rawread_readahead(vp,
325 udata +
326 bp->b_bufsize,
327 offset +
328 bp->b_bufsize,
329 resid -
330 bp->b_bufsize,
331 td,
332 nbp,
333 nsa);
334 if (nerror) {
335 pbrelvp(nbp);
336 relpbuf(nbp, &ffsrawbufcnt);
337 nbp = NULL;
338 }
339 }
340 }
341 }
342
343 spl = splbio();
344 bwait(bp, PRIBIO, "rawrd");
345 splx(spl);
346
347 vunmapbuf(bp);
348
349 iolen = bp->b_bcount - bp->b_resid;
350 if (iolen == 0 && (bp->b_ioflags & BIO_ERROR) == 0) {
351 nerror = 0; /* Ignore possible beyond EOF error */
352 break; /* EOF */
353 }
354
355 if ((bp->b_ioflags & BIO_ERROR) != 0) {
356 error = bp->b_error;
357 break;
358 }
359 resid -= iolen;
360 udata += iolen;
361 offset += iolen;
362 if (iolen < bp->b_bufsize) {
363 /* Incomplete read. Try to read remaining part */
364 error = ffs_rawread_readahead(vp,
365 udata,
366 offset,
367 bp->b_bufsize - iolen,
368 td,
369 bp,
370 sa);
371 if (error != 0)
372 break;
373 } else if (nbp != NULL) { /* Complete read with readahead */
374
375 tbp = bp;
376 bp = nbp;
377 nbp = tbp;
378
379 tsa = sa;
380 sa = nsa;
381 nsa = tsa;
382
383 if (resid <= bp->b_bufsize) { /* No more readaheads */
384 pbrelvp(nbp);
385 relpbuf(nbp, &ffsrawbufcnt);
386 nbp = NULL;
387 } else { /* Setup next readahead */
388 nerror = ffs_rawread_readahead(vp,
389 udata +
390 bp->b_bufsize,
391 offset +
392 bp->b_bufsize,
393 resid -
394 bp->b_bufsize,
395 td,
396 nbp,
397 nsa);
398 if (nerror != 0) {
399 pbrelvp(nbp);
400 relpbuf(nbp, &ffsrawbufcnt);
401 nbp = NULL;
402 }
403 }
404 } else if (nerror != 0) {/* Deferred Readahead error */
405 break;
406 } else if (resid > 0) { /* More to read, no readahead */
407 error = ffs_rawread_readahead(vp, udata, offset,
408 resid, td, bp, sa);
409 if (error != 0)
410 break;
411 }
412 }
413
414 if (bp != NULL) {
415 pbrelvp(bp);
416 relpbuf(bp, &ffsrawbufcnt);
417 }
418 if (nbp != NULL) { /* Run down readahead buffer */
419 spl = splbio();
420 bwait(nbp, PRIBIO, "rawrd");
421 splx(spl);
422 vunmapbuf(nbp);
423 pbrelvp(nbp);
424 relpbuf(nbp, &ffsrawbufcnt);
425 }
426
427 if (error == 0)
428 error = nerror;
429 PRELE(td->td_proc);
430 uio->uio_iov->iov_base = udata;
431 uio->uio_resid = resid;
432 uio->uio_offset = offset;
433 return error;
434}
435
436
437int
438ffs_rawread(struct vnode *vp,
439 struct uio *uio,
440 int *workdone)
441{
442 if (allowrawread != 0 &&
443 uio->uio_iovcnt == 1 &&
444 uio->uio_segflg == UIO_USERSPACE &&
445 uio->uio_resid == uio->uio_iov->iov_len &&
446 (((uio->uio_td != NULL) ? uio->uio_td : curthread)->td_pflags &
447 TDP_DEADLKTREAT) == 0) {
448 int secsize; /* Media sector size */
449 off_t filebytes; /* Bytes left of file */
450 int blockbytes; /* Bytes left of file in full blocks */
451 int partialbytes; /* Bytes in last partial block */
452 int skipbytes; /* Bytes not to read in ffs_rawread */
453 struct inode *ip;
454 int error;
455
456
457 /* Only handle sector aligned reads */
458 ip = VTOI(vp);
459 secsize = ip->i_devvp->v_bufobj.bo_bsize;
460 if ((uio->uio_offset & (secsize - 1)) == 0 &&
461 (uio->uio_resid & (secsize - 1)) == 0) {
462
463 /* Sync dirty pages and buffers if needed */
464 error = ffs_rawread_sync(vp);
465 if (error != 0)
466 return error;
467
468 /* Check for end of file */
469 if (ip->i_size > uio->uio_offset) {
470 filebytes = ip->i_size - uio->uio_offset;
471
472 /* No special eof handling needed ? */
473 if (uio->uio_resid <= filebytes) {
474 *workdone = 1;
475 return ffs_rawread_main(vp, uio);
476 }
477
478 partialbytes = ((unsigned int) ip->i_size) %
479 ip->i_fs->fs_bsize;
480 blockbytes = (int) filebytes - partialbytes;
481 if (blockbytes > 0) {
482 skipbytes = uio->uio_resid -
483 blockbytes;
484 uio->uio_resid = blockbytes;
485 error = ffs_rawread_main(vp, uio);
486 uio->uio_resid += skipbytes;
487 if (error != 0)
488 return error;
489 /* Read remaining part using buffer */
490 }
491 }
492 }
493 }
494 *workdone = 0;
495 return 0;
496}
| 150 } else
151 VI_UNLOCK(vp);
152
153 /* Wait for pending writes to complete */
154 BO_LOCK(bo);
155 error = bufobj_wwait(&vp->v_bufobj, 0, 0);
156 if (error != 0) {
157 /* XXX: can't happen with a zero timeout ??? */
158 BO_UNLOCK(bo);
159 if (upgraded != 0)
160 VOP_LOCK(vp, LK_DOWNGRADE);
161 vn_finished_write(mp);
162 return (error);
163 }
164 /* Flush dirty buffers */
165 if (bo->bo_dirty.bv_cnt > 0) {
166 BO_UNLOCK(bo);
167 if ((error = ffs_syncvnode(vp, MNT_WAIT, 0)) != 0) {
168 if (upgraded != 0)
169 VOP_LOCK(vp, LK_DOWNGRADE);
170 vn_finished_write(mp);
171 return (error);
172 }
173 BO_LOCK(bo);
174 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
175 panic("ffs_rawread_sync: dirty bufs");
176 }
177 BO_UNLOCK(bo);
178 if (upgraded != 0)
179 VOP_LOCK(vp, LK_DOWNGRADE);
180 vn_finished_write(mp);
181 } else {
182 VI_UNLOCK(vp);
183 BO_UNLOCK(bo);
184 }
185 return 0;
186}
187
188
189static int
190ffs_rawread_readahead(struct vnode *vp,
191 caddr_t udata,
192 off_t offset,
193 size_t len,
194 struct thread *td,
195 struct buf *bp,
196 caddr_t sa)
197{
198 int error;
199 u_int iolen;
200 off_t blockno;
201 int blockoff;
202 int bsize;
203 struct vnode *dp;
204 int bforwards;
205 struct inode *ip;
206 ufs2_daddr_t blkno;
207
208 bsize = vp->v_mount->mnt_stat.f_iosize;
209
210 ip = VTOI(vp);
211 dp = ip->i_devvp;
212
213 iolen = ((vm_offset_t) udata) & PAGE_MASK;
214 bp->b_bcount = len;
215 if (bp->b_bcount + iolen > bp->b_kvasize) {
216 bp->b_bcount = bp->b_kvasize;
217 if (iolen != 0)
218 bp->b_bcount -= PAGE_SIZE;
219 }
220 bp->b_flags = 0; /* XXX necessary ? */
221 bp->b_iocmd = BIO_READ;
222 bp->b_iodone = bdone;
223 bp->b_data = udata;
224 bp->b_saveaddr = sa;
225 blockno = offset / bsize;
226 blockoff = (offset % bsize) / DEV_BSIZE;
227 if ((daddr_t) blockno != blockno) {
228 return EINVAL; /* blockno overflow */
229 }
230
231 bp->b_lblkno = bp->b_blkno = blockno;
232
233 error = ufs_bmaparray(vp, bp->b_lblkno, &blkno, NULL, &bforwards, NULL);
234 if (error != 0)
235 return error;
236 if (blkno == -1) {
237
238 /* Fill holes with NULs to preserve semantics */
239
240 if (bp->b_bcount + blockoff * DEV_BSIZE > bsize)
241 bp->b_bcount = bsize - blockoff * DEV_BSIZE;
242 bp->b_bufsize = bp->b_bcount;
243
244 if (vmapbuf(bp) < 0)
245 return EFAULT;
246
247 maybe_yield();
248 bzero(bp->b_data, bp->b_bufsize);
249
250 /* Mark operation completed (similar to bufdone()) */
251
252 bp->b_resid = 0;
253 bp->b_flags |= B_DONE;
254 return 0;
255 }
256 bp->b_blkno = blkno + blockoff;
257 bp->b_offset = bp->b_iooffset = (blkno + blockoff) * DEV_BSIZE;
258
259 if (bp->b_bcount + blockoff * DEV_BSIZE > bsize * (1 + bforwards))
260 bp->b_bcount = bsize * (1 + bforwards) - blockoff * DEV_BSIZE;
261 bp->b_bufsize = bp->b_bcount;
262
263 if (vmapbuf(bp) < 0)
264 return EFAULT;
265
266 BO_STRATEGY(&dp->v_bufobj, bp);
267 return 0;
268}
269
270
271static int
272ffs_rawread_main(struct vnode *vp,
273 struct uio *uio)
274{
275 int error, nerror;
276 struct buf *bp, *nbp, *tbp;
277 caddr_t sa, nsa, tsa;
278 u_int iolen;
279 int spl;
280 caddr_t udata;
281 long resid;
282 off_t offset;
283 struct thread *td;
284
285 td = uio->uio_td ? uio->uio_td : curthread;
286 udata = uio->uio_iov->iov_base;
287 resid = uio->uio_resid;
288 offset = uio->uio_offset;
289
290 /*
291 * keep the process from being swapped
292 */
293 PHOLD(td->td_proc);
294
295 error = 0;
296 nerror = 0;
297
298 bp = NULL;
299 nbp = NULL;
300 sa = NULL;
301 nsa = NULL;
302
303 while (resid > 0) {
304
305 if (bp == NULL) { /* Setup first read */
306 /* XXX: Leave some bufs for swap */
307 bp = getpbuf(&ffsrawbufcnt);
308 sa = bp->b_data;
309 pbgetvp(vp, bp);
310 error = ffs_rawread_readahead(vp, udata, offset,
311 resid, td, bp, sa);
312 if (error != 0)
313 break;
314
315 if (resid > bp->b_bufsize) { /* Setup fist readahead */
316 /* XXX: Leave bufs for swap */
317 if (rawreadahead != 0)
318 nbp = trypbuf(&ffsrawbufcnt);
319 else
320 nbp = NULL;
321 if (nbp != NULL) {
322 nsa = nbp->b_data;
323 pbgetvp(vp, nbp);
324
325 nerror = ffs_rawread_readahead(vp,
326 udata +
327 bp->b_bufsize,
328 offset +
329 bp->b_bufsize,
330 resid -
331 bp->b_bufsize,
332 td,
333 nbp,
334 nsa);
335 if (nerror) {
336 pbrelvp(nbp);
337 relpbuf(nbp, &ffsrawbufcnt);
338 nbp = NULL;
339 }
340 }
341 }
342 }
343
344 spl = splbio();
345 bwait(bp, PRIBIO, "rawrd");
346 splx(spl);
347
348 vunmapbuf(bp);
349
350 iolen = bp->b_bcount - bp->b_resid;
351 if (iolen == 0 && (bp->b_ioflags & BIO_ERROR) == 0) {
352 nerror = 0; /* Ignore possible beyond EOF error */
353 break; /* EOF */
354 }
355
356 if ((bp->b_ioflags & BIO_ERROR) != 0) {
357 error = bp->b_error;
358 break;
359 }
360 resid -= iolen;
361 udata += iolen;
362 offset += iolen;
363 if (iolen < bp->b_bufsize) {
364 /* Incomplete read. Try to read remaining part */
365 error = ffs_rawread_readahead(vp,
366 udata,
367 offset,
368 bp->b_bufsize - iolen,
369 td,
370 bp,
371 sa);
372 if (error != 0)
373 break;
374 } else if (nbp != NULL) { /* Complete read with readahead */
375
376 tbp = bp;
377 bp = nbp;
378 nbp = tbp;
379
380 tsa = sa;
381 sa = nsa;
382 nsa = tsa;
383
384 if (resid <= bp->b_bufsize) { /* No more readaheads */
385 pbrelvp(nbp);
386 relpbuf(nbp, &ffsrawbufcnt);
387 nbp = NULL;
388 } else { /* Setup next readahead */
389 nerror = ffs_rawread_readahead(vp,
390 udata +
391 bp->b_bufsize,
392 offset +
393 bp->b_bufsize,
394 resid -
395 bp->b_bufsize,
396 td,
397 nbp,
398 nsa);
399 if (nerror != 0) {
400 pbrelvp(nbp);
401 relpbuf(nbp, &ffsrawbufcnt);
402 nbp = NULL;
403 }
404 }
405 } else if (nerror != 0) {/* Deferred Readahead error */
406 break;
407 } else if (resid > 0) { /* More to read, no readahead */
408 error = ffs_rawread_readahead(vp, udata, offset,
409 resid, td, bp, sa);
410 if (error != 0)
411 break;
412 }
413 }
414
415 if (bp != NULL) {
416 pbrelvp(bp);
417 relpbuf(bp, &ffsrawbufcnt);
418 }
419 if (nbp != NULL) { /* Run down readahead buffer */
420 spl = splbio();
421 bwait(nbp, PRIBIO, "rawrd");
422 splx(spl);
423 vunmapbuf(nbp);
424 pbrelvp(nbp);
425 relpbuf(nbp, &ffsrawbufcnt);
426 }
427
428 if (error == 0)
429 error = nerror;
430 PRELE(td->td_proc);
431 uio->uio_iov->iov_base = udata;
432 uio->uio_resid = resid;
433 uio->uio_offset = offset;
434 return error;
435}
436
437
438int
439ffs_rawread(struct vnode *vp,
440 struct uio *uio,
441 int *workdone)
442{
443 if (allowrawread != 0 &&
444 uio->uio_iovcnt == 1 &&
445 uio->uio_segflg == UIO_USERSPACE &&
446 uio->uio_resid == uio->uio_iov->iov_len &&
447 (((uio->uio_td != NULL) ? uio->uio_td : curthread)->td_pflags &
448 TDP_DEADLKTREAT) == 0) {
449 int secsize; /* Media sector size */
450 off_t filebytes; /* Bytes left of file */
451 int blockbytes; /* Bytes left of file in full blocks */
452 int partialbytes; /* Bytes in last partial block */
453 int skipbytes; /* Bytes not to read in ffs_rawread */
454 struct inode *ip;
455 int error;
456
457
458 /* Only handle sector aligned reads */
459 ip = VTOI(vp);
460 secsize = ip->i_devvp->v_bufobj.bo_bsize;
461 if ((uio->uio_offset & (secsize - 1)) == 0 &&
462 (uio->uio_resid & (secsize - 1)) == 0) {
463
464 /* Sync dirty pages and buffers if needed */
465 error = ffs_rawread_sync(vp);
466 if (error != 0)
467 return error;
468
469 /* Check for end of file */
470 if (ip->i_size > uio->uio_offset) {
471 filebytes = ip->i_size - uio->uio_offset;
472
473 /* No special eof handling needed ? */
474 if (uio->uio_resid <= filebytes) {
475 *workdone = 1;
476 return ffs_rawread_main(vp, uio);
477 }
478
479 partialbytes = ((unsigned int) ip->i_size) %
480 ip->i_fs->fs_bsize;
481 blockbytes = (int) filebytes - partialbytes;
482 if (blockbytes > 0) {
483 skipbytes = uio->uio_resid -
484 blockbytes;
485 uio->uio_resid = blockbytes;
486 error = ffs_rawread_main(vp, uio);
487 uio->uio_resid += skipbytes;
488 if (error != 0)
489 return error;
490 /* Read remaining part using buffer */
491 }
492 }
493 }
494 }
495 *workdone = 0;
496 return 0;
497}
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