xref: /openbmc/linux/fs/freevxfs/vxfs_inode.c (revision 643d1f7f)
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 /*
31  * Veritas filesystem driver - inode routines.
32  */
33 #include <linux/fs.h>
34 #include <linux/buffer_head.h>
35 #include <linux/pagemap.h>
36 #include <linux/kernel.h>
37 #include <linux/slab.h>
38 
39 #include "vxfs.h"
40 #include "vxfs_inode.h"
41 #include "vxfs_extern.h"
42 
43 
44 extern const struct address_space_operations vxfs_aops;
45 extern const struct address_space_operations vxfs_immed_aops;
46 
47 extern const struct inode_operations vxfs_immed_symlink_iops;
48 
49 struct kmem_cache		*vxfs_inode_cachep;
50 
51 
52 #ifdef DIAGNOSTIC
53 /*
54  * Dump inode contents (partially).
55  */
56 void
57 vxfs_dumpi(struct vxfs_inode_info *vip, ino_t ino)
58 {
59 	printk(KERN_DEBUG "\n\n");
60 	if (ino)
61 		printk(KERN_DEBUG "dumping vxfs inode %ld\n", ino);
62 	else
63 		printk(KERN_DEBUG "dumping unknown vxfs inode\n");
64 
65 	printk(KERN_DEBUG "---------------------------\n");
66 	printk(KERN_DEBUG "mode is %x\n", vip->vii_mode);
67 	printk(KERN_DEBUG "nlink:%u, uid:%u, gid:%u\n",
68 			vip->vii_nlink, vip->vii_uid, vip->vii_gid);
69 	printk(KERN_DEBUG "size:%Lx, blocks:%u\n",
70 			vip->vii_size, vip->vii_blocks);
71 	printk(KERN_DEBUG "orgtype:%u\n", vip->vii_orgtype);
72 }
73 #endif
74 
75 
76 /**
77  * vxfs_blkiget - find inode based on extent #
78  * @sbp:	superblock of the filesystem we search in
79  * @extent:	number of the extent to search
80  * @ino:	inode number to search
81  *
82  * Description:
83  *  vxfs_blkiget searches inode @ino in the filesystem described by
84  *  @sbp in the extent @extent.
85  *  Returns the matching VxFS inode on success, else a NULL pointer.
86  *
87  * NOTE:
88  *  While __vxfs_iget uses the pagecache vxfs_blkiget uses the
89  *  buffercache.  This function should not be used outside the
90  *  read_super() method, otherwise the data may be incoherent.
91  */
92 struct vxfs_inode_info *
93 vxfs_blkiget(struct super_block *sbp, u_long extent, ino_t ino)
94 {
95 	struct buffer_head		*bp;
96 	u_long				block, offset;
97 
98 	block = extent + ((ino * VXFS_ISIZE) / sbp->s_blocksize);
99 	offset = ((ino % (sbp->s_blocksize / VXFS_ISIZE)) * VXFS_ISIZE);
100 	bp = sb_bread(sbp, block);
101 
102 	if (bp && buffer_mapped(bp)) {
103 		struct vxfs_inode_info	*vip;
104 		struct vxfs_dinode	*dip;
105 
106 		if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
107 			goto fail;
108 		dip = (struct vxfs_dinode *)(bp->b_data + offset);
109 		memcpy(vip, dip, sizeof(*vip));
110 #ifdef DIAGNOSTIC
111 		vxfs_dumpi(vip, ino);
112 #endif
113 		brelse(bp);
114 		return (vip);
115 	}
116 
117 fail:
118 	printk(KERN_WARNING "vxfs: unable to read block %ld\n", block);
119 	brelse(bp);
120 	return NULL;
121 }
122 
123 /**
124  * __vxfs_iget - generic find inode facility
125  * @sbp:		VFS superblock
126  * @ino:		inode number
127  * @ilistp:		inode list
128  *
129  * Description:
130  *  Search the for inode number @ino in the filesystem
131  *  described by @sbp.  Use the specified inode table (@ilistp).
132  *  Returns the matching VxFS inode on success, else a NULL pointer.
133  */
134 static struct vxfs_inode_info *
135 __vxfs_iget(ino_t ino, struct inode *ilistp)
136 {
137 	struct page			*pp;
138 	u_long				offset;
139 
140 	offset = (ino % (PAGE_SIZE / VXFS_ISIZE)) * VXFS_ISIZE;
141 	pp = vxfs_get_page(ilistp->i_mapping, ino * VXFS_ISIZE / PAGE_SIZE);
142 
143 	if (!IS_ERR(pp)) {
144 		struct vxfs_inode_info	*vip;
145 		struct vxfs_dinode	*dip;
146 		caddr_t			kaddr = (char *)page_address(pp);
147 
148 		if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
149 			goto fail;
150 		dip = (struct vxfs_dinode *)(kaddr + offset);
151 		memcpy(vip, dip, sizeof(*vip));
152 #ifdef DIAGNOSTIC
153 		vxfs_dumpi(vip, ino);
154 #endif
155 		vxfs_put_page(pp);
156 		return (vip);
157 	}
158 
159 	printk(KERN_WARNING "vxfs: error on page %p\n", pp);
160 	return NULL;
161 
162 fail:
163 	printk(KERN_WARNING "vxfs: unable to read inode %ld\n", (unsigned long)ino);
164 	vxfs_put_page(pp);
165 	return NULL;
166 }
167 
168 /**
169  * vxfs_stiget - find inode using the structural inode list
170  * @sbp:	VFS superblock
171  * @ino:	inode #
172  *
173  * Description:
174  *  Find inode @ino in the filesystem described by @sbp using
175  *  the structural inode list.
176  *  Returns the matching VxFS inode on success, else a NULL pointer.
177  */
178 struct vxfs_inode_info *
179 vxfs_stiget(struct super_block *sbp, ino_t ino)
180 {
181         return __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_stilist);
182 }
183 
184 /**
185  * vxfs_transmod - mode for a VxFS inode
186  * @vip:	VxFS inode
187  *
188  * Description:
189  *  vxfs_transmod returns a Linux mode_t for a given
190  *  VxFS inode structure.
191  */
192 static __inline__ mode_t
193 vxfs_transmod(struct vxfs_inode_info *vip)
194 {
195 	mode_t			ret = vip->vii_mode & ~VXFS_TYPE_MASK;
196 
197 	if (VXFS_ISFIFO(vip))
198 		ret |= S_IFIFO;
199 	if (VXFS_ISCHR(vip))
200 		ret |= S_IFCHR;
201 	if (VXFS_ISDIR(vip))
202 		ret |= S_IFDIR;
203 	if (VXFS_ISBLK(vip))
204 		ret |= S_IFBLK;
205 	if (VXFS_ISLNK(vip))
206 		ret |= S_IFLNK;
207 	if (VXFS_ISREG(vip))
208 		ret |= S_IFREG;
209 	if (VXFS_ISSOC(vip))
210 		ret |= S_IFSOCK;
211 
212 	return (ret);
213 }
214 
215 /**
216  * vxfs_iinit- helper to fill inode fields
217  * @ip:		VFS inode
218  * @vip:	VxFS inode
219  *
220  * Description:
221  *  vxfs_instino is a helper function to fill in all relevant
222  *  fields in @ip from @vip.
223  */
224 static void
225 vxfs_iinit(struct inode *ip, struct vxfs_inode_info *vip)
226 {
227 
228 	ip->i_mode = vxfs_transmod(vip);
229 	ip->i_uid = (uid_t)vip->vii_uid;
230 	ip->i_gid = (gid_t)vip->vii_gid;
231 
232 	ip->i_nlink = vip->vii_nlink;
233 	ip->i_size = vip->vii_size;
234 
235 	ip->i_atime.tv_sec = vip->vii_atime;
236 	ip->i_ctime.tv_sec = vip->vii_ctime;
237 	ip->i_mtime.tv_sec = vip->vii_mtime;
238 	ip->i_atime.tv_nsec = 0;
239 	ip->i_ctime.tv_nsec = 0;
240 	ip->i_mtime.tv_nsec = 0;
241 
242 	ip->i_blocks = vip->vii_blocks;
243 	ip->i_generation = vip->vii_gen;
244 
245 	ip->i_private = vip;
246 
247 }
248 
249 /**
250  * vxfs_get_fake_inode - get fake inode structure
251  * @sbp:		filesystem superblock
252  * @vip:		fspriv inode
253  *
254  * Description:
255  *  vxfs_fake_inode gets a fake inode (not in the inode hash) for a
256  *  superblock, vxfs_inode pair.
257  *  Returns the filled VFS inode.
258  */
259 struct inode *
260 vxfs_get_fake_inode(struct super_block *sbp, struct vxfs_inode_info *vip)
261 {
262 	struct inode			*ip = NULL;
263 
264 	if ((ip = new_inode(sbp))) {
265 		vxfs_iinit(ip, vip);
266 		ip->i_mapping->a_ops = &vxfs_aops;
267 	}
268 	return (ip);
269 }
270 
271 /**
272  * vxfs_put_fake_inode - free faked inode
273  * *ip:			VFS inode
274  *
275  * Description:
276  *  vxfs_put_fake_inode frees all data asssociated with @ip.
277  */
278 void
279 vxfs_put_fake_inode(struct inode *ip)
280 {
281 	iput(ip);
282 }
283 
284 /**
285  * vxfs_read_inode - fill in inode information
286  * @ip:		inode pointer to fill
287  *
288  * Description:
289  *  vxfs_read_inode reads the disk inode for @ip and fills
290  *  in all relevant fields in @ip.
291  */
292 void
293 vxfs_read_inode(struct inode *ip)
294 {
295 	struct super_block		*sbp = ip->i_sb;
296 	struct vxfs_inode_info		*vip;
297 	const struct address_space_operations	*aops;
298 	ino_t				ino = ip->i_ino;
299 
300 	if (!(vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_ilist)))
301 		return;
302 
303 	vxfs_iinit(ip, vip);
304 
305 	if (VXFS_ISIMMED(vip))
306 		aops = &vxfs_immed_aops;
307 	else
308 		aops = &vxfs_aops;
309 
310 	if (S_ISREG(ip->i_mode)) {
311 		ip->i_fop = &generic_ro_fops;
312 		ip->i_mapping->a_ops = aops;
313 	} else if (S_ISDIR(ip->i_mode)) {
314 		ip->i_op = &vxfs_dir_inode_ops;
315 		ip->i_fop = &vxfs_dir_operations;
316 		ip->i_mapping->a_ops = aops;
317 	} else if (S_ISLNK(ip->i_mode)) {
318 		if (!VXFS_ISIMMED(vip)) {
319 			ip->i_op = &page_symlink_inode_operations;
320 			ip->i_mapping->a_ops = &vxfs_aops;
321 		} else
322 			ip->i_op = &vxfs_immed_symlink_iops;
323 	} else
324 		init_special_inode(ip, ip->i_mode, old_decode_dev(vip->vii_rdev));
325 
326 	return;
327 }
328 
329 /**
330  * vxfs_clear_inode - remove inode from main memory
331  * @ip:		inode to discard.
332  *
333  * Description:
334  *  vxfs_clear_inode() is called on the final iput and frees the private
335  *  inode area.
336  */
337 void
338 vxfs_clear_inode(struct inode *ip)
339 {
340 	kmem_cache_free(vxfs_inode_cachep, ip->i_private);
341 }
342