1/*
2 * Copyright (c) 2000-2001 Christoph Hellwig.
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 *    without modification.
11 * 2. The name of the author may not be used to endorse or promote products
12 *    derived from this software without specific prior written permission.
13 *
14 * Alternatively, this software may be distributed under the terms of the
15 * GNU General Public License ("GPL").
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#ident "$Id: vxfs_inode.c,v 1.1.1.1 2008/10/15 03:27:06 james26_jang Exp $"
31
32/*
33 * Veritas filesystem driver - inode routines.
34 */
35#include <linux/fs.h>
36#include <linux/pagemap.h>
37#include <linux/kernel.h>
38#include <linux/slab.h>
39
40#include "vxfs.h"
41#include "vxfs_inode.h"
42#include "vxfs_extern.h"
43
44
45extern struct address_space_operations vxfs_aops;
46extern struct address_space_operations vxfs_immed_aops;
47
48extern struct inode_operations vxfs_immed_symlink_iops;
49
50static struct file_operations vxfs_file_operations = {
51	.open =			generic_file_open,
52	.llseek =		generic_file_llseek,
53	.read =			generic_file_read,
54	.mmap =			generic_file_mmap,
55};
56
57
58kmem_cache_t		*vxfs_inode_cachep;
59
60
61#ifdef DIAGNOSTIC
62/*
63 * Dump inode contents (partially).
64 */
65void
66vxfs_dumpi(struct vxfs_inode_info *vip, ino_t ino)
67{
68	printk(KERN_DEBUG "\n\n");
69	if (ino)
70		printk(KERN_DEBUG "dumping vxfs inode %ld\n", ino);
71	else
72		printk(KERN_DEBUG "dumping unknown vxfs inode\n");
73
74	printk(KERN_DEBUG "---------------------------\n");
75	printk(KERN_DEBUG "mode is %x\n", vip->vii_mode);
76	printk(KERN_DEBUG "nlink:%u, uid:%u, gid:%u\n",
77			vip->vii_nlink, vip->vii_uid, vip->vii_gid);
78	printk(KERN_DEBUG "size:%Lx, blocks:%u\n",
79			vip->vii_size, vip->vii_blocks);
80	printk(KERN_DEBUG "orgtype:%u\n", vip->vii_orgtype);
81}
82#endif
83
84
85/**
86 * vxfs_blkiget - find inode based on extent #
87 * @sbp:	superblock of the filesystem we search in
88 * @extent:	number of the extent to search
89 * @ino:	inode number to search
90 *
91 * Description:
92 *  vxfs_blkiget searches inode @ino in the filesystem described by
93 *  @sbp in the extent @extent.
94 *  Returns the matching VxFS inode on success, else a NULL pointer.
95 *
96 * NOTE:
97 *  While __vxfs_iget uses the pagecache vxfs_blkiget uses the
98 *  buffercache.  This function should not be used outside the
99 *  read_super() method, otherwise the data may be incoherent.
100 */
101struct vxfs_inode_info *
102vxfs_blkiget(struct super_block *sbp, u_long extent, ino_t ino)
103{
104	struct buffer_head		*bp;
105	u_long				block, offset;
106
107	block = extent + ((ino * VXFS_ISIZE) / sbp->s_blocksize);
108	offset = ((ino % (sbp->s_blocksize / VXFS_ISIZE)) * VXFS_ISIZE);
109	bp = sb_bread(sbp, block);
110
111	if (buffer_mapped(bp)) {
112		struct vxfs_inode_info	*vip;
113		struct vxfs_dinode	*dip;
114
115		if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, SLAB_KERNEL)))
116			goto fail;
117		dip = (struct vxfs_dinode *)(bp->b_data + offset);
118		memcpy(vip, dip, sizeof(*vip));
119#ifdef DIAGNOSTIC
120		vxfs_dumpi(vip, ino);
121#endif
122		brelse(bp);
123		return (vip);
124	}
125
126fail:
127	printk(KERN_WARNING "vxfs: unable to read block %ld\n", block);
128	brelse(bp);
129	return NULL;
130}
131
132/**
133 * __vxfs_iget - generic find inode facility
134 * @sbp:		VFS superblock
135 * @ino:		inode number
136 * @ilistp:		inode list
137 *
138 * Description:
139 *  Search the for inode number @ino in the filesystem
140 *  described by @sbp.  Use the specified inode table (@ilistp).
141 *  Returns the matching VxFS inode on success, else a NULL pointer.
142 */
143static struct vxfs_inode_info *
144__vxfs_iget(ino_t ino, struct inode *ilistp)
145{
146	struct page			*pp;
147	u_long				offset;
148
149	offset = (ino % (PAGE_SIZE / VXFS_ISIZE)) * VXFS_ISIZE;
150	pp = vxfs_get_page(ilistp->i_mapping, ino * VXFS_ISIZE / PAGE_SIZE);
151
152	if (!IS_ERR(pp)) {
153		struct vxfs_inode_info	*vip;
154		struct vxfs_dinode	*dip;
155		caddr_t			kaddr = (char *)page_address(pp);
156
157		if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, SLAB_KERNEL)))
158			goto fail;
159		dip = (struct vxfs_dinode *)(kaddr + offset);
160		memcpy(vip, dip, sizeof(*vip));
161#ifdef DIAGNOSTIC
162		vxfs_dumpi(vip, ino);
163#endif
164		vxfs_put_page(pp);
165		return (vip);
166	}
167
168	printk(KERN_WARNING "vxfs: error on page %p\n", pp);
169	return NULL;
170
171fail:
172	printk(KERN_WARNING "vxfs: unable to read inode %ld\n", ino);
173	vxfs_put_page(pp);
174	return NULL;
175}
176
177/**
178 * vxfs_stiget - find inode using the structural inode list
179 * @sbp:	VFS superblock
180 * @ino:	inode #
181 *
182 * Description:
183 *  Find inode @ino in the filesystem described by @sbp using
184 *  the structural inode list.
185 *  Returns the matching VxFS inode on success, else a NULL pointer.
186 */
187struct vxfs_inode_info *
188vxfs_stiget(struct super_block *sbp, ino_t ino)
189{
190        return __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_stilist);
191}
192
193/**
194 * vxfs_transmod - mode for a VxFS inode
195 * @vip:	VxFS inode
196 *
197 * Description:
198 *  vxfs_transmod returns a Linux mode_t for a given
199 *  VxFS inode structure.
200 */
201static __inline__ mode_t
202vxfs_transmod(struct vxfs_inode_info *vip)
203{
204	mode_t			ret = vip->vii_mode & ~VXFS_TYPE_MASK;
205
206	if (VXFS_ISFIFO(vip))
207		ret |= S_IFIFO;
208	if (VXFS_ISCHR(vip))
209		ret |= S_IFCHR;
210	if (VXFS_ISDIR(vip))
211		ret |= S_IFDIR;
212	if (VXFS_ISBLK(vip))
213		ret |= S_IFBLK;
214	if (VXFS_ISLNK(vip))
215		ret |= S_IFLNK;
216	if (VXFS_ISREG(vip))
217		ret |= S_IFREG;
218	if (VXFS_ISSOC(vip))
219		ret |= S_IFSOCK;
220
221	return (ret);
222}
223
224/**
225 * vxfs_iinit- helper to fill inode fields
226 * @ip:		VFS inode
227 * @vip:	VxFS inode
228 *
229 * Description:
230 *  vxfs_instino is a helper function to fill in all relevant
231 *  fields in @ip from @vip.
232 */
233static void
234vxfs_iinit(struct inode *ip, struct vxfs_inode_info *vip)
235{
236
237	ip->i_mode = vxfs_transmod(vip);
238	ip->i_uid = (uid_t)vip->vii_uid;
239	ip->i_gid = (gid_t)vip->vii_gid;
240
241	ip->i_nlink = vip->vii_nlink;
242	ip->i_size = vip->vii_size;
243
244	ip->i_atime = vip->vii_atime;
245	ip->i_ctime = vip->vii_ctime;
246	ip->i_mtime = vip->vii_mtime;
247
248	ip->i_blksize = PAGE_SIZE;
249	ip->i_blocks = vip->vii_blocks;
250	ip->i_generation = vip->vii_gen;
251
252	ip->u.generic_ip = (void *)vip;
253
254}
255
256/**
257 * vxfs_get_fake_inode - get fake inode structure
258 * @sbp:		filesystem superblock
259 * @vip:		fspriv inode
260 *
261 * Description:
262 *  vxfs_fake_inode gets a fake inode (not in the inode hash) for a
263 *  superblock, vxfs_inode pair.
264 *  Returns the filled VFS inode.
265 */
266struct inode *
267vxfs_get_fake_inode(struct super_block *sbp, struct vxfs_inode_info *vip)
268{
269	struct inode			*ip = NULL;
270
271	if ((ip = new_inode(sbp))) {
272		vxfs_iinit(ip, vip);
273		ip->i_mapping->a_ops = &vxfs_aops;
274	}
275	return (ip);
276}
277
278/**
279 * vxfs_put_fake_inode - free faked inode
280 * *ip:			VFS inode
281 *
282 * Description:
283 *  vxfs_put_fake_inode frees all data asssociated with @ip.
284 */
285void
286vxfs_put_fake_inode(struct inode *ip)
287{
288	iput(ip);
289}
290
291/**
292 * vxfs_read_inode - fill in inode information
293 * @ip:		inode pointer to fill
294 *
295 * Description:
296 *  vxfs_read_inode reads the disk inode for @ip and fills
297 *  in all relevant fields in @ip.
298 */
299void
300vxfs_read_inode(struct inode *ip)
301{
302	struct super_block		*sbp = ip->i_sb;
303	struct vxfs_inode_info		*vip;
304	struct address_space_operations	*aops;
305	ino_t				ino = ip->i_ino;
306
307	if (!(vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_ilist)))
308		return;
309
310	vxfs_iinit(ip, vip);
311
312	if (VXFS_ISIMMED(vip))
313		aops = &vxfs_immed_aops;
314	else
315		aops = &vxfs_aops;
316
317	if (S_ISREG(ip->i_mode)) {
318		ip->i_fop = &vxfs_file_operations;
319		ip->i_mapping->a_ops = aops;
320	} else if (S_ISDIR(ip->i_mode)) {
321		ip->i_op = &vxfs_dir_inode_ops;
322		ip->i_fop = &vxfs_dir_operations;
323		ip->i_mapping->a_ops = aops;
324	} else if (S_ISLNK(ip->i_mode)) {
325		if (!VXFS_ISIMMED(vip)) {
326			ip->i_op = &page_symlink_inode_operations;
327			ip->i_mapping->a_ops = &vxfs_aops;
328		} else
329			ip->i_op = &vxfs_immed_symlink_iops;
330	} else
331		init_special_inode(ip, ip->i_mode, vip->vii_rdev);
332
333	return;
334}
335
336/**
337 * vxfs_put_inode - remove inode from main memory
338 * @ip:		inode to discard.
339 *
340 * Description:
341 *  vxfs_put_inode() is called on each iput.  If we are the last
342 *  link in memory, free the fspriv inode area.
343 */
344void
345vxfs_put_inode(struct inode *ip)
346{
347	if (atomic_read(&ip->i_count) == 1)
348		kmem_cache_free(vxfs_inode_cachep, ip->u.generic_ip);
349}
350