1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate * CDDL HEADER START
3*7c478bd9Sstevel@tonic-gate *
4*7c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*7c478bd9Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*7c478bd9Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*7c478bd9Sstevel@tonic-gate * with the License.
8*7c478bd9Sstevel@tonic-gate *
9*7c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*7c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*7c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions
12*7c478bd9Sstevel@tonic-gate * and limitations under the License.
13*7c478bd9Sstevel@tonic-gate *
14*7c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*7c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*7c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*7c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*7c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*7c478bd9Sstevel@tonic-gate *
20*7c478bd9Sstevel@tonic-gate * CDDL HEADER END
21*7c478bd9Sstevel@tonic-gate */
22*7c478bd9Sstevel@tonic-gate /*
23*7c478bd9Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
24*7c478bd9Sstevel@tonic-gate * Use is subject to license terms.
25*7c478bd9Sstevel@tonic-gate */
26*7c478bd9Sstevel@tonic-gate
27*7c478bd9Sstevel@tonic-gate #include <sys/systm.h>
28*7c478bd9Sstevel@tonic-gate #include <sys/types.h>
29*7c478bd9Sstevel@tonic-gate #include <sys/vnode.h>
30*7c478bd9Sstevel@tonic-gate #include <sys/file.h>
31*7c478bd9Sstevel@tonic-gate #include <sys/buf.h>
32*7c478bd9Sstevel@tonic-gate #include <sys/ddi.h>
33*7c478bd9Sstevel@tonic-gate #include <sys/errno.h>
34*7c478bd9Sstevel@tonic-gate #include <sys/cmn_err.h>
35*7c478bd9Sstevel@tonic-gate #include <sys/fs/ufs_inode.h>
36*7c478bd9Sstevel@tonic-gate #include <sys/fs/ufs_filio.h>
37*7c478bd9Sstevel@tonic-gate #include <sys/fs/ufs_snap.h>
38*7c478bd9Sstevel@tonic-gate #include <sys/fssnap_if.h>
39*7c478bd9Sstevel@tonic-gate #include <sys/sysmacros.h>
40*7c478bd9Sstevel@tonic-gate #include <sys/modctl.h>
41*7c478bd9Sstevel@tonic-gate #include <sys/fs/ufs_bio.h>
42*7c478bd9Sstevel@tonic-gate #include <sys/debug.h>
43*7c478bd9Sstevel@tonic-gate #include <sys/kmem.h>
44*7c478bd9Sstevel@tonic-gate #include <sys/inttypes.h>
45*7c478bd9Sstevel@tonic-gate #include <sys/vfs.h>
46*7c478bd9Sstevel@tonic-gate #include <sys/disp.h>
47*7c478bd9Sstevel@tonic-gate #include <sys/atomic.h>
48*7c478bd9Sstevel@tonic-gate #include <sys/conf.h>
49*7c478bd9Sstevel@tonic-gate #include <sys/param.h>
50*7c478bd9Sstevel@tonic-gate #include <sys/policy.h>
51*7c478bd9Sstevel@tonic-gate
52*7c478bd9Sstevel@tonic-gate static int ufs_snap_init_backfile(int *, int, vnode_t ***, struct ufsvfs *);
53*7c478bd9Sstevel@tonic-gate static void release_backing_vnodes(vnode_t ***, int);
54*7c478bd9Sstevel@tonic-gate static int ufs_snap_find_candidates(void *, struct ufsvfs *, int);
55*7c478bd9Sstevel@tonic-gate
56*7c478bd9Sstevel@tonic-gate /*
57*7c478bd9Sstevel@tonic-gate * Create a snapshot on a file system
58*7c478bd9Sstevel@tonic-gate */
59*7c478bd9Sstevel@tonic-gate int
ufs_snap_create(struct vnode * vp,struct fiosnapcreate_multi * fiosnapp,cred_t * cr)60*7c478bd9Sstevel@tonic-gate ufs_snap_create(struct vnode *vp, struct fiosnapcreate_multi *fiosnapp,
61*7c478bd9Sstevel@tonic-gate cred_t *cr)
62*7c478bd9Sstevel@tonic-gate {
63*7c478bd9Sstevel@tonic-gate int error = 0;
64*7c478bd9Sstevel@tonic-gate struct ufsvfs *ufsvfsp = VTOI(vp)->i_ufsvfs;
65*7c478bd9Sstevel@tonic-gate struct fs *fs = ufsvfsp->vfs_fs;
66*7c478bd9Sstevel@tonic-gate vnode_t **bfvpp = NULL;
67*7c478bd9Sstevel@tonic-gate struct lockfs lf;
68*7c478bd9Sstevel@tonic-gate void *snapid = NULL;
69*7c478bd9Sstevel@tonic-gate
70*7c478bd9Sstevel@tonic-gate u_offset_t nchunks;
71*7c478bd9Sstevel@tonic-gate uint_t chunksize, fragsperchunk;
72*7c478bd9Sstevel@tonic-gate
73*7c478bd9Sstevel@tonic-gate /*
74*7c478bd9Sstevel@tonic-gate * Only privilege processes can create a snapshot for now. This
75*7c478bd9Sstevel@tonic-gate * would be better if it was based on the permissions of the device
76*7c478bd9Sstevel@tonic-gate * file.
77*7c478bd9Sstevel@tonic-gate */
78*7c478bd9Sstevel@tonic-gate if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
79*7c478bd9Sstevel@tonic-gate return (EPERM);
80*7c478bd9Sstevel@tonic-gate
81*7c478bd9Sstevel@tonic-gate /*
82*7c478bd9Sstevel@tonic-gate * There is no reason to make a snapshot of a read-only file system
83*7c478bd9Sstevel@tonic-gate */
84*7c478bd9Sstevel@tonic-gate if (fs->fs_ronly) {
85*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_EREADONLY;
86*7c478bd9Sstevel@tonic-gate return (EROFS);
87*7c478bd9Sstevel@tonic-gate }
88*7c478bd9Sstevel@tonic-gate
89*7c478bd9Sstevel@tonic-gate /*
90*7c478bd9Sstevel@tonic-gate * Initialize the backing files to store old data. This assumes any
91*7c478bd9Sstevel@tonic-gate * preallocation and setup has been done already.
92*7c478bd9Sstevel@tonic-gate * ufs_snap_init_backfile() allocates and returns a pointer to
93*7c478bd9Sstevel@tonic-gate * a null-terminated array of vnodes in bfvpp.
94*7c478bd9Sstevel@tonic-gate */
95*7c478bd9Sstevel@tonic-gate error = ufs_snap_init_backfile(fiosnapp->backfiledesc,
96*7c478bd9Sstevel@tonic-gate fiosnapp->backfilecount, &bfvpp, ufsvfsp);
97*7c478bd9Sstevel@tonic-gate if (error) {
98*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_EBACKFILE;
99*7c478bd9Sstevel@tonic-gate return (error);
100*7c478bd9Sstevel@tonic-gate }
101*7c478bd9Sstevel@tonic-gate
102*7c478bd9Sstevel@tonic-gate /*
103*7c478bd9Sstevel@tonic-gate * File system must be write locked to prevent updates while
104*7c478bd9Sstevel@tonic-gate * the snapshot is being established.
105*7c478bd9Sstevel@tonic-gate */
106*7c478bd9Sstevel@tonic-gate if ((error = ufs_fiolfss(vp, &lf)) != 0) {
107*7c478bd9Sstevel@tonic-gate release_backing_vnodes(&bfvpp, fiosnapp->backfilecount);
108*7c478bd9Sstevel@tonic-gate return (error);
109*7c478bd9Sstevel@tonic-gate }
110*7c478bd9Sstevel@tonic-gate
111*7c478bd9Sstevel@tonic-gate if (!LOCKFS_IS_ULOCK(&lf)) {
112*7c478bd9Sstevel@tonic-gate release_backing_vnodes(&bfvpp, fiosnapp->backfilecount);
113*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_EULOCK;
114*7c478bd9Sstevel@tonic-gate return (EINVAL);
115*7c478bd9Sstevel@tonic-gate }
116*7c478bd9Sstevel@tonic-gate
117*7c478bd9Sstevel@tonic-gate lf.lf_lock = LOCKFS_WLOCK;
118*7c478bd9Sstevel@tonic-gate lf.lf_flags = 0;
119*7c478bd9Sstevel@tonic-gate lf.lf_comment = NULL;
120*7c478bd9Sstevel@tonic-gate if ((error = ufs_fiolfs(vp, &lf, 1)) != 0) {
121*7c478bd9Sstevel@tonic-gate release_backing_vnodes(&bfvpp, fiosnapp->backfilecount);
122*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_EWLOCK;
123*7c478bd9Sstevel@tonic-gate return (EINVAL);
124*7c478bd9Sstevel@tonic-gate }
125*7c478bd9Sstevel@tonic-gate
126*7c478bd9Sstevel@tonic-gate /*
127*7c478bd9Sstevel@tonic-gate * File system must be fairly consistent to enable snapshots
128*7c478bd9Sstevel@tonic-gate */
129*7c478bd9Sstevel@tonic-gate if (fs->fs_clean != FSACTIVE &&
130*7c478bd9Sstevel@tonic-gate fs->fs_clean != FSSTABLE &&
131*7c478bd9Sstevel@tonic-gate fs->fs_clean != FSCLEAN &&
132*7c478bd9Sstevel@tonic-gate fs->fs_clean != FSLOG) {
133*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_ECLEAN;
134*7c478bd9Sstevel@tonic-gate error = EINVAL;
135*7c478bd9Sstevel@tonic-gate goto unlockout;
136*7c478bd9Sstevel@tonic-gate }
137*7c478bd9Sstevel@tonic-gate
138*7c478bd9Sstevel@tonic-gate /*
139*7c478bd9Sstevel@tonic-gate * Only one snapshot is allowed per file system, so error if
140*7c478bd9Sstevel@tonic-gate * a snapshot is already enabled.
141*7c478bd9Sstevel@tonic-gate */
142*7c478bd9Sstevel@tonic-gate if (ufsvfsp->vfs_snapshot) {
143*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_EBUSY;
144*7c478bd9Sstevel@tonic-gate error = EBUSY;
145*7c478bd9Sstevel@tonic-gate goto unlockout;
146*7c478bd9Sstevel@tonic-gate }
147*7c478bd9Sstevel@tonic-gate
148*7c478bd9Sstevel@tonic-gate /* Tell bio.c how to call our strategy routine. XXX ugly hack */
149*7c478bd9Sstevel@tonic-gate if (bio_snapshot_strategy == NULL)
150*7c478bd9Sstevel@tonic-gate bio_snapshot_strategy =
151*7c478bd9Sstevel@tonic-gate (void (*) (void *, buf_t *))fssnap_strategy;
152*7c478bd9Sstevel@tonic-gate
153*7c478bd9Sstevel@tonic-gate /*
154*7c478bd9Sstevel@tonic-gate * use chunk size that is passed in, or the file system
155*7c478bd9Sstevel@tonic-gate * block size if it is zero. For most cases, the file system
156*7c478bd9Sstevel@tonic-gate * block size will be reasonably efficient. A larger
157*7c478bd9Sstevel@tonic-gate * chunksize uses less memory but may potentially induce more
158*7c478bd9Sstevel@tonic-gate * I/O copying the larger chunks aside.
159*7c478bd9Sstevel@tonic-gate */
160*7c478bd9Sstevel@tonic-gate if (fiosnapp->chunksize != 0)
161*7c478bd9Sstevel@tonic-gate chunksize = fiosnapp->chunksize;
162*7c478bd9Sstevel@tonic-gate else
163*7c478bd9Sstevel@tonic-gate chunksize = fs->fs_bsize * 4;
164*7c478bd9Sstevel@tonic-gate
165*7c478bd9Sstevel@tonic-gate
166*7c478bd9Sstevel@tonic-gate /*
167*7c478bd9Sstevel@tonic-gate * compute the number of chunks in this whole file system. Since
168*7c478bd9Sstevel@tonic-gate * the UFS allocation bitmaps are in units of fragments, we first
169*7c478bd9Sstevel@tonic-gate * compute the number of fragments per chunk. Things work out
170*7c478bd9Sstevel@tonic-gate * nicer if the chunk size is a power-of-two multiple of the
171*7c478bd9Sstevel@tonic-gate * fragment size.
172*7c478bd9Sstevel@tonic-gate */
173*7c478bd9Sstevel@tonic-gate if ((chunksize < fs->fs_fsize) || (chunksize % fs->fs_fsize != 0)) {
174*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_ECHUNKSZ;
175*7c478bd9Sstevel@tonic-gate error = EINVAL;
176*7c478bd9Sstevel@tonic-gate goto unlockout;
177*7c478bd9Sstevel@tonic-gate }
178*7c478bd9Sstevel@tonic-gate fragsperchunk = chunksize >> fs->fs_fshift;
179*7c478bd9Sstevel@tonic-gate nchunks = (fs->fs_size + fragsperchunk) / fragsperchunk;
180*7c478bd9Sstevel@tonic-gate
181*7c478bd9Sstevel@tonic-gate /*
182*7c478bd9Sstevel@tonic-gate * Create and initialize snapshot state and allocate/initialize
183*7c478bd9Sstevel@tonic-gate * translation table. This does the real work of taking the snapshot.
184*7c478bd9Sstevel@tonic-gate */
185*7c478bd9Sstevel@tonic-gate snapid = fssnap_create(nchunks, chunksize, fiosnapp->maxsize, vp,
186*7c478bd9Sstevel@tonic-gate fiosnapp->backfilecount, bfvpp, fiosnapp->backfilename,
187*7c478bd9Sstevel@tonic-gate fiosnapp->backfilesize);
188*7c478bd9Sstevel@tonic-gate if (snapid == NULL) {
189*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_ECREATE;
190*7c478bd9Sstevel@tonic-gate error = EINVAL;
191*7c478bd9Sstevel@tonic-gate goto unlockout;
192*7c478bd9Sstevel@tonic-gate }
193*7c478bd9Sstevel@tonic-gate
194*7c478bd9Sstevel@tonic-gate error = ufs_snap_find_candidates(snapid, ufsvfsp, chunksize);
195*7c478bd9Sstevel@tonic-gate fiosnapp->snapshotnumber = fssnap_create_done(snapid);
196*7c478bd9Sstevel@tonic-gate
197*7c478bd9Sstevel@tonic-gate if (error) {
198*7c478bd9Sstevel@tonic-gate cmn_err(CE_WARN, "ufs_snap_create: failed scanning bitmaps, "
199*7c478bd9Sstevel@tonic-gate "error = %d.", error);
200*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_EBITMAP;
201*7c478bd9Sstevel@tonic-gate goto unlockout;
202*7c478bd9Sstevel@tonic-gate }
203*7c478bd9Sstevel@tonic-gate
204*7c478bd9Sstevel@tonic-gate ufsvfsp->vfs_snapshot = snapid;
205*7c478bd9Sstevel@tonic-gate
206*7c478bd9Sstevel@tonic-gate unlockout:
207*7c478bd9Sstevel@tonic-gate /*
208*7c478bd9Sstevel@tonic-gate * Unlock the file system
209*7c478bd9Sstevel@tonic-gate */
210*7c478bd9Sstevel@tonic-gate lf.lf_lock = LOCKFS_ULOCK;
211*7c478bd9Sstevel@tonic-gate lf.lf_flags = 0;
212*7c478bd9Sstevel@tonic-gate if ((ufs_fiolfs(vp, &lf, 1) != 0) && !error) {
213*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_ENOULOCK;
214*7c478bd9Sstevel@tonic-gate error = EINVAL;
215*7c478bd9Sstevel@tonic-gate } else {
216*7c478bd9Sstevel@tonic-gate fiosnapp->error = 0;
217*7c478bd9Sstevel@tonic-gate }
218*7c478bd9Sstevel@tonic-gate
219*7c478bd9Sstevel@tonic-gate /* clean up the snapshot if an error occurred. */
220*7c478bd9Sstevel@tonic-gate if (error && snapid != NULL)
221*7c478bd9Sstevel@tonic-gate (void) fssnap_delete(&snapid);
222*7c478bd9Sstevel@tonic-gate else if (error && bfvpp != NULL)
223*7c478bd9Sstevel@tonic-gate release_backing_vnodes(&bfvpp, fiosnapp->backfilecount);
224*7c478bd9Sstevel@tonic-gate
225*7c478bd9Sstevel@tonic-gate return (error);
226*7c478bd9Sstevel@tonic-gate }
227*7c478bd9Sstevel@tonic-gate
228*7c478bd9Sstevel@tonic-gate static int
ufs_snap_init_backfile(int * filedesc,int count,vnode_t *** vppp,struct ufsvfs * ufsvfsp)229*7c478bd9Sstevel@tonic-gate ufs_snap_init_backfile(int *filedesc, int count, vnode_t ***vppp,
230*7c478bd9Sstevel@tonic-gate struct ufsvfs *ufsvfsp)
231*7c478bd9Sstevel@tonic-gate {
232*7c478bd9Sstevel@tonic-gate file_t *fp;
233*7c478bd9Sstevel@tonic-gate vnode_t **vpp;
234*7c478bd9Sstevel@tonic-gate int i;
235*7c478bd9Sstevel@tonic-gate
236*7c478bd9Sstevel@tonic-gate vpp = (vnode_t **)kmem_zalloc((count + 1) * sizeof (vnode_t *),
237*7c478bd9Sstevel@tonic-gate KM_SLEEP);
238*7c478bd9Sstevel@tonic-gate *vppp = vpp;
239*7c478bd9Sstevel@tonic-gate for (i = 0; i < count; i++) {
240*7c478bd9Sstevel@tonic-gate if ((fp = getf(*filedesc)) == NULL) {
241*7c478bd9Sstevel@tonic-gate release_backing_vnodes(vppp, count);
242*7c478bd9Sstevel@tonic-gate *vppp = NULL;
243*7c478bd9Sstevel@tonic-gate return (EBADF);
244*7c478bd9Sstevel@tonic-gate }
245*7c478bd9Sstevel@tonic-gate
246*7c478bd9Sstevel@tonic-gate ASSERT(fp->f_vnode != NULL);
247*7c478bd9Sstevel@tonic-gate VN_HOLD(fp->f_vnode);
248*7c478bd9Sstevel@tonic-gate
249*7c478bd9Sstevel@tonic-gate *vpp = fp->f_vnode;
250*7c478bd9Sstevel@tonic-gate releasef(*filedesc);
251*7c478bd9Sstevel@tonic-gate filedesc++;
252*7c478bd9Sstevel@tonic-gate
253*7c478bd9Sstevel@tonic-gate /* make sure the backing file is on a different file system */
254*7c478bd9Sstevel@tonic-gate if ((*vpp)->v_vfsp == ufsvfsp->vfs_vfs) {
255*7c478bd9Sstevel@tonic-gate release_backing_vnodes(vppp, count);
256*7c478bd9Sstevel@tonic-gate *vppp = NULL;
257*7c478bd9Sstevel@tonic-gate return (EINVAL);
258*7c478bd9Sstevel@tonic-gate }
259*7c478bd9Sstevel@tonic-gate vpp++;
260*7c478bd9Sstevel@tonic-gate }
261*7c478bd9Sstevel@tonic-gate return (0);
262*7c478bd9Sstevel@tonic-gate }
263*7c478bd9Sstevel@tonic-gate
264*7c478bd9Sstevel@tonic-gate static void
release_backing_vnodes(vnode_t *** bvppp,int count)265*7c478bd9Sstevel@tonic-gate release_backing_vnodes(vnode_t ***bvppp, int count)
266*7c478bd9Sstevel@tonic-gate {
267*7c478bd9Sstevel@tonic-gate vnode_t **vpp;
268*7c478bd9Sstevel@tonic-gate
269*7c478bd9Sstevel@tonic-gate vpp = *bvppp;
270*7c478bd9Sstevel@tonic-gate while (*vpp) {
271*7c478bd9Sstevel@tonic-gate VN_RELE(*vpp);
272*7c478bd9Sstevel@tonic-gate *vpp++ = NULL;
273*7c478bd9Sstevel@tonic-gate }
274*7c478bd9Sstevel@tonic-gate kmem_free(*bvppp, (count + 1) * sizeof (vnode_t *));
275*7c478bd9Sstevel@tonic-gate *bvppp = NULL;
276*7c478bd9Sstevel@tonic-gate }
277*7c478bd9Sstevel@tonic-gate
278*7c478bd9Sstevel@tonic-gate static int
ufs_snap_find_candidates(void * snapid,struct ufsvfs * ufsvfsp,int chunksize)279*7c478bd9Sstevel@tonic-gate ufs_snap_find_candidates(void *snapid, struct ufsvfs *ufsvfsp, int chunksize)
280*7c478bd9Sstevel@tonic-gate {
281*7c478bd9Sstevel@tonic-gate struct fs *fs = ufsvfsp->vfs_fs;
282*7c478bd9Sstevel@tonic-gate struct buf *cgbp; /* cylinder group buffer */
283*7c478bd9Sstevel@tonic-gate struct cg *cgp; /* cylinder group data */
284*7c478bd9Sstevel@tonic-gate ulong_t cg;
285*7c478bd9Sstevel@tonic-gate ulong_t cgbase;
286*7c478bd9Sstevel@tonic-gate ulong_t chunk;
287*7c478bd9Sstevel@tonic-gate uchar_t *blksfree;
288*7c478bd9Sstevel@tonic-gate
289*7c478bd9Sstevel@tonic-gate ulong_t curfrag;
290*7c478bd9Sstevel@tonic-gate int error = 0;
291*7c478bd9Sstevel@tonic-gate
292*7c478bd9Sstevel@tonic-gate /*
293*7c478bd9Sstevel@tonic-gate * read through each ufs cylinder group and fetch the fragment
294*7c478bd9Sstevel@tonic-gate * allocation bitmap. UFS indicates a fragment is allocated by
295*7c478bd9Sstevel@tonic-gate * a zero bit (not a one bit) in the fragment offset.
296*7c478bd9Sstevel@tonic-gate */
297*7c478bd9Sstevel@tonic-gate cgbase = 0LL;
298*7c478bd9Sstevel@tonic-gate for (cg = 0; cg < fs->fs_ncg; cg++) {
299*7c478bd9Sstevel@tonic-gate /* read the cylinder group in */
300*7c478bd9Sstevel@tonic-gate cgbp = BREAD(ufsvfsp->vfs_dev,
301*7c478bd9Sstevel@tonic-gate (daddr_t)fsbtodb(fs, cgtod(fs, cg)), (int)fs->fs_cgsize);
302*7c478bd9Sstevel@tonic-gate if ((error = geterror(cgbp)) != 0) {
303*7c478bd9Sstevel@tonic-gate brelse(cgbp);
304*7c478bd9Sstevel@tonic-gate goto errout;
305*7c478bd9Sstevel@tonic-gate }
306*7c478bd9Sstevel@tonic-gate cgp = cgbp->b_un.b_cg;
307*7c478bd9Sstevel@tonic-gate
308*7c478bd9Sstevel@tonic-gate /* check the magic number */
309*7c478bd9Sstevel@tonic-gate if (cgp->cg_magic != CG_MAGIC) {
310*7c478bd9Sstevel@tonic-gate cmn_err(CE_WARN, "ufs_snap_find_candidates: cg %lu "
311*7c478bd9Sstevel@tonic-gate "magic number (0x%x) does not match expected "
312*7c478bd9Sstevel@tonic-gate "magic number (0x%x)", cg, cgp->cg_magic, CG_MAGIC);
313*7c478bd9Sstevel@tonic-gate error = EIO;
314*7c478bd9Sstevel@tonic-gate goto errout;
315*7c478bd9Sstevel@tonic-gate }
316*7c478bd9Sstevel@tonic-gate
317*7c478bd9Sstevel@tonic-gate blksfree = cg_blksfree(cgp);
318*7c478bd9Sstevel@tonic-gate
319*7c478bd9Sstevel@tonic-gate /*
320*7c478bd9Sstevel@tonic-gate * go through the allocation bitmap and set the
321*7c478bd9Sstevel@tonic-gate * corresponding bit in the candidate map.
322*7c478bd9Sstevel@tonic-gate */
323*7c478bd9Sstevel@tonic-gate for (curfrag = 0; curfrag < cgp->cg_ndblk; curfrag++) {
324*7c478bd9Sstevel@tonic-gate if (isclr(blksfree, curfrag)) {
325*7c478bd9Sstevel@tonic-gate /*
326*7c478bd9Sstevel@tonic-gate * this assumes chunksize is a multiple of
327*7c478bd9Sstevel@tonic-gate * the fragment size
328*7c478bd9Sstevel@tonic-gate */
329*7c478bd9Sstevel@tonic-gate chunk = (ulong_t)((cgbase + curfrag) /
330*7c478bd9Sstevel@tonic-gate (chunksize >> fs->fs_fshift));
331*7c478bd9Sstevel@tonic-gate
332*7c478bd9Sstevel@tonic-gate fssnap_set_candidate(snapid, chunk);
333*7c478bd9Sstevel@tonic-gate /*
334*7c478bd9Sstevel@tonic-gate * no need to scan the rest of this chunk since
335*7c478bd9Sstevel@tonic-gate * it is already marked, so skip to the next
336*7c478bd9Sstevel@tonic-gate */
337*7c478bd9Sstevel@tonic-gate curfrag += ((chunksize >> fs->fs_fshift) -
338*7c478bd9Sstevel@tonic-gate ((cgbase + curfrag) %
339*7c478bd9Sstevel@tonic-gate (chunksize >> fs->fs_fshift))) - 1;
340*7c478bd9Sstevel@tonic-gate }
341*7c478bd9Sstevel@tonic-gate }
342*7c478bd9Sstevel@tonic-gate
343*7c478bd9Sstevel@tonic-gate cgbase += cgp->cg_ndblk;
344*7c478bd9Sstevel@tonic-gate ASSERT(cgbase <= fs->fs_size);
345*7c478bd9Sstevel@tonic-gate brelse(cgbp);
346*7c478bd9Sstevel@tonic-gate } /* cylinder group loop */
347*7c478bd9Sstevel@tonic-gate
348*7c478bd9Sstevel@tonic-gate ASSERT(cgbase == fs->fs_size);
349*7c478bd9Sstevel@tonic-gate
350*7c478bd9Sstevel@tonic-gate errout:
351*7c478bd9Sstevel@tonic-gate return (error);
352*7c478bd9Sstevel@tonic-gate }
353*7c478bd9Sstevel@tonic-gate
354*7c478bd9Sstevel@tonic-gate
355*7c478bd9Sstevel@tonic-gate int
ufs_snap_delete(struct vnode * vp,struct fiosnapdelete * fiosnapp,cred_t * cr)356*7c478bd9Sstevel@tonic-gate ufs_snap_delete(struct vnode *vp, struct fiosnapdelete *fiosnapp, cred_t *cr)
357*7c478bd9Sstevel@tonic-gate {
358*7c478bd9Sstevel@tonic-gate struct ufsvfs *ufsvfsp = VTOI(vp)->i_ufsvfs;
359*7c478bd9Sstevel@tonic-gate struct fs *fs = ufsvfsp->vfs_fs;
360*7c478bd9Sstevel@tonic-gate
361*7c478bd9Sstevel@tonic-gate /*
362*7c478bd9Sstevel@tonic-gate * Initialize fields in the user's buffer
363*7c478bd9Sstevel@tonic-gate */
364*7c478bd9Sstevel@tonic-gate fiosnapp->error = 0;
365*7c478bd9Sstevel@tonic-gate
366*7c478bd9Sstevel@tonic-gate /*
367*7c478bd9Sstevel@tonic-gate * No snapshot exists, we're done.
368*7c478bd9Sstevel@tonic-gate */
369*7c478bd9Sstevel@tonic-gate if (ufsvfsp->vfs_snapshot == NULL)
370*7c478bd9Sstevel@tonic-gate return (ENOENT);
371*7c478bd9Sstevel@tonic-gate
372*7c478bd9Sstevel@tonic-gate /*
373*7c478bd9Sstevel@tonic-gate * must have sufficient privileges.
374*7c478bd9Sstevel@tonic-gate */
375*7c478bd9Sstevel@tonic-gate if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
376*7c478bd9Sstevel@tonic-gate return (EPERM);
377*7c478bd9Sstevel@tonic-gate
378*7c478bd9Sstevel@tonic-gate /*
379*7c478bd9Sstevel@tonic-gate * Readonly file system
380*7c478bd9Sstevel@tonic-gate */
381*7c478bd9Sstevel@tonic-gate if (fs->fs_ronly) {
382*7c478bd9Sstevel@tonic-gate fiosnapp->error = FIOCOW_EREADONLY;
383*7c478bd9Sstevel@tonic-gate return (EROFS);
384*7c478bd9Sstevel@tonic-gate }
385*7c478bd9Sstevel@tonic-gate
386*7c478bd9Sstevel@tonic-gate /* free the data structures and clear the vfs_snapshot field. */
387*7c478bd9Sstevel@tonic-gate fiosnapp->snapshotnumber = fssnap_delete(&ufsvfsp->vfs_snapshot);
388*7c478bd9Sstevel@tonic-gate
389*7c478bd9Sstevel@tonic-gate if (fiosnapp->snapshotnumber == -1)
390*7c478bd9Sstevel@tonic-gate return (EINVAL);
391*7c478bd9Sstevel@tonic-gate
392*7c478bd9Sstevel@tonic-gate return (0);
393*7c478bd9Sstevel@tonic-gate }
394