1/*	$NetBSD: filecore_bmap.c,v 1.8 2008/05/16 09:21:59 hannken Exp $	*/
2
3/*-
4 * Copyright (c) 1994 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	filecore_bmap.c		1.1	1998/6/26
32 */
33
34/*-
35 * Copyright (c) 1998 Andrew McMurry
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 *    notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 *    notice, this list of conditions and the following disclaimer in the
44 *    documentation and/or other materials provided with the distribution.
45 * 3. All advertising materials mentioning features or use of this software
46 *    must display the following acknowledgement:
47 *	This product includes software developed by the University of
48 *	California, Berkeley and its contributors.
49 * 4. Neither the name of the University nor the names of its contributors
50 *    may be used to endorse or promote products derived from this software
51 *    without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 *	filecore_bmap.c		1.1	1998/6/26
66 */
67
68#include <sys/cdefs.h>
69__KERNEL_RCSID(0, "$NetBSD: filecore_bmap.c,v 1.8 2008/05/16 09:21:59 hannken Exp $");
70
71#include <sys/param.h>
72#include <sys/systm.h>
73#include <sys/namei.h>
74#include <sys/buf.h>
75#include <sys/file.h>
76#include <sys/vnode.h>
77#include <sys/mount.h>
78#include <sys/kauth.h>
79
80#include <fs/filecorefs/filecore.h>
81#include <fs/filecorefs/filecore_extern.h>
82#include <fs/filecorefs/filecore_node.h>
83
84/*
85 * Bmap converts a the logical block number of a file to its physical block
86 * number on the disk. The conversion is done by using the logical block
87 * number to index into the data block (extent) for the file.
88 */
89int
90filecore_bmap(void *v)
91{
92	struct vop_bmap_args /* {
93		struct vnode *a_vp;
94		daddr_t a_bn;
95		struct vnode **a_vpp;
96		daddr_t *a_bnp;
97		int *a_runp;
98	} */ *ap = v;
99	struct filecore_node *ip = VTOI(ap->a_vp);
100	struct filecore_mnt *fcmp = ip->i_mnt;
101	daddr_t lbn = ap->a_bn;
102
103	/*
104	 * Check for underlying vnode requests and ensure that logical
105	 * to physical mapping is requested.
106	 */
107	if (ap->a_vpp != NULL)
108		*ap->a_vpp = ip->i_devvp;
109	if (ap->a_bnp == NULL)
110		return (0);
111
112	/*
113	 * Determine maximum number of readahead blocks following the
114	 * requested block.
115	 */
116	if (ap->a_runp) {
117		int nblk;
118		int bshift=fcmp->log2bsize;
119
120		nblk = (ip->i_size >> bshift) - (lbn + 1);
121		if (nblk <= 0)
122			*ap->a_runp = 0;
123		else if (nblk >= (MAXBSIZE >> bshift))
124			*ap->a_runp = (MAXBSIZE >> bshift) - 1;
125		else
126			*ap->a_runp = nblk;
127	}
128	/*
129	 * Compute the requested block number
130	 */
131	return filecore_map(fcmp, ip->i_dirent.addr, lbn, ap->a_bnp);
132}
133
134int
135filecore_map(struct filecore_mnt *fcmp, u_int32_t addr, daddr_t lbn, daddr_t *bnp)
136{
137	struct buf *bp;
138	u_long frag, sect, zone, izone, a, b, m, n;
139	u_int64_t zaddr;
140	u_long *ptr;
141	long c;
142	int error = 0;
143
144#ifdef FILECORE_DEBUG
145	printf("filecore_map(addr=%x, lbn=%llx)\n", addr, (long long)lbn);
146#endif
147	frag = addr >> 8;
148	sect = (addr & 0xff) +
149		((lbn << fcmp->log2bsize) >> fcmp->drec.log2secsize);
150	if (frag != 2)
151		zone = frag / fcmp->idspz;
152	else
153		zone = fcmp->drec.nzones / 2;
154	izone = zone;
155	if (zone != 0)
156		zaddr=((8<<fcmp->drec.log2secsize)-fcmp->drec.zone_spare)*zone
157		  - 8*FILECORE_DISCREC_SIZE;
158	else
159		zaddr = 0;
160	if (sect > 0)
161		sect--;
162	sect <<= fcmp->drec.share_size;
163	do {
164		error=bread(fcmp->fc_devvp, fcmp->map + zone,
165			    1 << fcmp->drec.log2secsize, NOCRED, 0, &bp);
166#ifdef FILECORE_DEBUG_BR
167		printf("bread(%p, %lx, %d, CRED, %p)=%d\n", fcmp->fc_devvp,
168		       fcmp->map+zone, 1 << fcmp->drec.log2secsize, bp, error);
169		printf("block is at %p\n", bp->b_data);
170#endif
171		if (error != 0) {
172#ifdef FILECORE_DEBUG_BR
173			printf("brelse(%p) bm1\n", bp);
174#endif
175			brelse(bp, 0);
176			return error;
177		}
178		ptr = (u_long *)(bp->b_data) + 1; /* skip map zone header */
179		if (zone == 0)
180			ptr += FILECORE_DISCREC_SIZE >> 2;
181		b = 0;
182		while (b < (8 << (fcmp->drec.log2secsize))
183		   - fcmp->drec.zone_spare) {
184			a = ptr[b >> 5] >> (b & 31);
185			c = 32 - (b & 31) - fcmp->drec.idlen;
186			if (c <= 0) {
187				m = ptr[(b >> 5) + 1];
188				a |= m << (fcmp->drec.idlen+c);
189				m >>= -c;
190				c += 32;
191			} else
192				m = a >> fcmp->drec.idlen;
193			n = fcmp->drec.idlen + 1;
194			while ((m & 1) == 0) {
195				m >>= 1;
196				n++;
197				if (--c == 0) {
198					c=32;
199					m = ptr[(b + n - 1) >> 5];
200				}
201			}
202			a &= fcmp->mask;
203			if (a == frag) {
204				if (sect << fcmp->drec.log2secsize < n
205				    << fcmp->drec.log2bpmb) {
206					*bnp = (((zaddr+b)
207					    << fcmp->drec.log2bpmb)
208					    >> fcmp->drec.log2secsize) + sect;
209
210#ifdef FILECORE_DEBUG_BR
211					printf("brelse(%p) bm2\n", bp);
212#endif
213					brelse(bp, 0);
214					return 0;
215				} else
216					sect -= (n<<fcmp->drec.log2bpmb)
217					    >> fcmp->drec.log2secsize;
218			}
219			b += n;
220		}
221#ifdef FILECORE_DEBUG_BR
222		printf("brelse(%p) bm3\n", bp);
223#endif
224		brelse(bp, 0);
225		if (++zone == fcmp->drec.nzones) {
226			zone = 0;
227			zaddr=0;
228		} else
229			zaddr += ((8 << fcmp->drec.log2secsize)
230			    - fcmp->drec.zone_spare);
231	} while (zone != izone);
232	return (E2BIG);
233}
234
235int
236filecore_bread(struct filecore_mnt *fcmp, u_int32_t addr, int size, kauth_cred_t cred, struct buf **bp)
237{
238	int error = 0;
239	daddr_t bn;
240
241	error = filecore_map(fcmp, addr, 0, &bn);
242	if (error) {
243
244#ifdef FILECORE_DEBUG
245		printf("filecore_bread(error=%d)\n", error);
246#endif
247		return error;
248	}
249	error = bread(fcmp->fc_devvp, bn, size, cred, 0, bp);
250#ifdef FILECORE_DEBUG_BR
251	printf("bread(%p, %llx, %d, CRED, %p)=%d\n", fcmp->fc_devvp,
252	    (long long)bn, size, *bp, error);
253#endif
254	return error;
255}
256
257int
258filecore_dbread(struct filecore_node *ip, struct buf **bp)
259{
260	int error = 0;
261
262	if (ip->i_block == -1)
263		error = filecore_map(ip->i_mnt, ip->i_dirent.addr,
264			0, &(ip->i_block));
265	if (error)
266		return error;
267	error = bread(ip->i_mnt->fc_devvp, ip->i_block, FILECORE_DIR_SIZE,
268		      NOCRED, 0, bp);
269#ifdef FILECORE_DEBUG_BR
270	printf("bread(%p, %llx, %d, CRED, %p)=%d\n", ip->i_mnt->fc_devvp,
271	       (long long)ip->i_block, FILECORE_DIR_SIZE, *bp, error);
272#endif
273	return error;
274}
275