xref: /openbmc/linux/fs/freevxfs/vxfs_inode.c (revision 3805e6a1)
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 #include <linux/namei.h>
39 
40 #include "vxfs.h"
41 #include "vxfs_inode.h"
42 #include "vxfs_extern.h"
43 
44 
45 struct kmem_cache		*vxfs_inode_cachep;
46 
47 
48 #ifdef DIAGNOSTIC
49 /*
50  * Dump inode contents (partially).
51  */
52 void
53 vxfs_dumpi(struct vxfs_inode_info *vip, ino_t ino)
54 {
55 	printk(KERN_DEBUG "\n\n");
56 	if (ino)
57 		printk(KERN_DEBUG "dumping vxfs inode %ld\n", ino);
58 	else
59 		printk(KERN_DEBUG "dumping unknown vxfs inode\n");
60 
61 	printk(KERN_DEBUG "---------------------------\n");
62 	printk(KERN_DEBUG "mode is %x\n", vip->vii_mode);
63 	printk(KERN_DEBUG "nlink:%u, uid:%u, gid:%u\n",
64 			vip->vii_nlink, vip->vii_uid, vip->vii_gid);
65 	printk(KERN_DEBUG "size:%Lx, blocks:%u\n",
66 			vip->vii_size, vip->vii_blocks);
67 	printk(KERN_DEBUG "orgtype:%u\n", vip->vii_orgtype);
68 }
69 #endif
70 
71 
72 /**
73  * vxfs_blkiget - find inode based on extent #
74  * @sbp:	superblock of the filesystem we search in
75  * @extent:	number of the extent to search
76  * @ino:	inode number to search
77  *
78  * Description:
79  *  vxfs_blkiget searches inode @ino in the filesystem described by
80  *  @sbp in the extent @extent.
81  *  Returns the matching VxFS inode on success, else a NULL pointer.
82  *
83  * NOTE:
84  *  While __vxfs_iget uses the pagecache vxfs_blkiget uses the
85  *  buffercache.  This function should not be used outside the
86  *  read_super() method, otherwise the data may be incoherent.
87  */
88 struct vxfs_inode_info *
89 vxfs_blkiget(struct super_block *sbp, u_long extent, ino_t ino)
90 {
91 	struct buffer_head		*bp;
92 	u_long				block, offset;
93 
94 	block = extent + ((ino * VXFS_ISIZE) / sbp->s_blocksize);
95 	offset = ((ino % (sbp->s_blocksize / VXFS_ISIZE)) * VXFS_ISIZE);
96 	bp = sb_bread(sbp, block);
97 
98 	if (bp && buffer_mapped(bp)) {
99 		struct vxfs_inode_info	*vip;
100 		struct vxfs_dinode	*dip;
101 
102 		if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
103 			goto fail;
104 		dip = (struct vxfs_dinode *)(bp->b_data + offset);
105 		memcpy(vip, dip, sizeof(*vip));
106 #ifdef DIAGNOSTIC
107 		vxfs_dumpi(vip, ino);
108 #endif
109 		brelse(bp);
110 		return (vip);
111 	}
112 
113 fail:
114 	printk(KERN_WARNING "vxfs: unable to read block %ld\n", block);
115 	brelse(bp);
116 	return NULL;
117 }
118 
119 /**
120  * __vxfs_iget - generic find inode facility
121  * @sbp:		VFS superblock
122  * @ino:		inode number
123  * @ilistp:		inode list
124  *
125  * Description:
126  *  Search the for inode number @ino in the filesystem
127  *  described by @sbp.  Use the specified inode table (@ilistp).
128  *  Returns the matching VxFS inode on success, else an error code.
129  */
130 static struct vxfs_inode_info *
131 __vxfs_iget(ino_t ino, struct inode *ilistp)
132 {
133 	struct page			*pp;
134 	u_long				offset;
135 
136 	offset = (ino % (PAGE_SIZE / VXFS_ISIZE)) * VXFS_ISIZE;
137 	pp = vxfs_get_page(ilistp->i_mapping, ino * VXFS_ISIZE / PAGE_SIZE);
138 
139 	if (!IS_ERR(pp)) {
140 		struct vxfs_inode_info	*vip;
141 		struct vxfs_dinode	*dip;
142 		caddr_t			kaddr = (char *)page_address(pp);
143 
144 		if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
145 			goto fail;
146 		dip = (struct vxfs_dinode *)(kaddr + offset);
147 		memcpy(vip, dip, sizeof(*vip));
148 #ifdef DIAGNOSTIC
149 		vxfs_dumpi(vip, ino);
150 #endif
151 		vxfs_put_page(pp);
152 		return (vip);
153 	}
154 
155 	printk(KERN_WARNING "vxfs: error on page %p\n", pp);
156 	return ERR_CAST(pp);
157 
158 fail:
159 	printk(KERN_WARNING "vxfs: unable to read inode %ld\n", (unsigned long)ino);
160 	vxfs_put_page(pp);
161 	return ERR_PTR(-ENOMEM);
162 }
163 
164 /**
165  * vxfs_stiget - find inode using the structural inode list
166  * @sbp:	VFS superblock
167  * @ino:	inode #
168  *
169  * Description:
170  *  Find inode @ino in the filesystem described by @sbp using
171  *  the structural inode list.
172  *  Returns the matching VxFS inode on success, else a NULL pointer.
173  */
174 struct vxfs_inode_info *
175 vxfs_stiget(struct super_block *sbp, ino_t ino)
176 {
177 	struct vxfs_inode_info *vip;
178 
179 	vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_stilist);
180 	return IS_ERR(vip) ? NULL : vip;
181 }
182 
183 /**
184  * vxfs_transmod - mode for a VxFS inode
185  * @vip:	VxFS inode
186  *
187  * Description:
188  *  vxfs_transmod returns a Linux mode_t for a given
189  *  VxFS inode structure.
190  */
191 static __inline__ umode_t
192 vxfs_transmod(struct vxfs_inode_info *vip)
193 {
194 	umode_t			ret = vip->vii_mode & ~VXFS_TYPE_MASK;
195 
196 	if (VXFS_ISFIFO(vip))
197 		ret |= S_IFIFO;
198 	if (VXFS_ISCHR(vip))
199 		ret |= S_IFCHR;
200 	if (VXFS_ISDIR(vip))
201 		ret |= S_IFDIR;
202 	if (VXFS_ISBLK(vip))
203 		ret |= S_IFBLK;
204 	if (VXFS_ISLNK(vip))
205 		ret |= S_IFLNK;
206 	if (VXFS_ISREG(vip))
207 		ret |= S_IFREG;
208 	if (VXFS_ISSOC(vip))
209 		ret |= S_IFSOCK;
210 
211 	return (ret);
212 }
213 
214 /**
215  * vxfs_iinit- helper to fill inode fields
216  * @ip:		VFS inode
217  * @vip:	VxFS inode
218  *
219  * Description:
220  *  vxfs_instino is a helper function to fill in all relevant
221  *  fields in @ip from @vip.
222  */
223 static void
224 vxfs_iinit(struct inode *ip, struct vxfs_inode_info *vip)
225 {
226 
227 	ip->i_mode = vxfs_transmod(vip);
228 	i_uid_write(ip, (uid_t)vip->vii_uid);
229 	i_gid_write(ip, (gid_t)vip->vii_gid);
230 
231 	set_nlink(ip, vip->vii_nlink);
232 	ip->i_size = vip->vii_size;
233 
234 	ip->i_atime.tv_sec = vip->vii_atime;
235 	ip->i_ctime.tv_sec = vip->vii_ctime;
236 	ip->i_mtime.tv_sec = vip->vii_mtime;
237 	ip->i_atime.tv_nsec = 0;
238 	ip->i_ctime.tv_nsec = 0;
239 	ip->i_mtime.tv_nsec = 0;
240 
241 	ip->i_blocks = vip->vii_blocks;
242 	ip->i_generation = vip->vii_gen;
243 
244 	ip->i_private = vip;
245 
246 }
247 
248 /**
249  * vxfs_get_fake_inode - get fake inode structure
250  * @sbp:		filesystem superblock
251  * @vip:		fspriv inode
252  *
253  * Description:
254  *  vxfs_fake_inode gets a fake inode (not in the inode hash) for a
255  *  superblock, vxfs_inode pair.
256  *  Returns the filled VFS inode.
257  */
258 struct inode *
259 vxfs_get_fake_inode(struct super_block *sbp, struct vxfs_inode_info *vip)
260 {
261 	struct inode			*ip = NULL;
262 
263 	if ((ip = new_inode(sbp))) {
264 		ip->i_ino = get_next_ino();
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 associated with @ip.
277  */
278 void
279 vxfs_put_fake_inode(struct inode *ip)
280 {
281 	iput(ip);
282 }
283 
284 /**
285  * vxfs_iget - get an inode
286  * @sbp:	the superblock to get the inode for
287  * @ino:	the number of the inode to get
288  *
289  * Description:
290  *  vxfs_read_inode creates an inode, reads the disk inode for @ino and fills
291  *  in all relevant fields in the new inode.
292  */
293 struct inode *
294 vxfs_iget(struct super_block *sbp, ino_t ino)
295 {
296 	struct vxfs_inode_info		*vip;
297 	const struct address_space_operations	*aops;
298 	struct inode *ip;
299 
300 	ip = iget_locked(sbp, ino);
301 	if (!ip)
302 		return ERR_PTR(-ENOMEM);
303 	if (!(ip->i_state & I_NEW))
304 		return ip;
305 
306 	vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_ilist);
307 	if (IS_ERR(vip)) {
308 		iget_failed(ip);
309 		return ERR_CAST(vip);
310 	}
311 
312 	vxfs_iinit(ip, vip);
313 
314 	if (VXFS_ISIMMED(vip))
315 		aops = &vxfs_immed_aops;
316 	else
317 		aops = &vxfs_aops;
318 
319 	if (S_ISREG(ip->i_mode)) {
320 		ip->i_fop = &generic_ro_fops;
321 		ip->i_mapping->a_ops = aops;
322 	} else if (S_ISDIR(ip->i_mode)) {
323 		ip->i_op = &vxfs_dir_inode_ops;
324 		ip->i_fop = &vxfs_dir_operations;
325 		ip->i_mapping->a_ops = aops;
326 	} else if (S_ISLNK(ip->i_mode)) {
327 		if (!VXFS_ISIMMED(vip)) {
328 			ip->i_op = &page_symlink_inode_operations;
329 			inode_nohighmem(ip);
330 			ip->i_mapping->a_ops = &vxfs_aops;
331 		} else {
332 			ip->i_op = &simple_symlink_inode_operations;
333 			ip->i_link = vip->vii_immed.vi_immed;
334 			nd_terminate_link(ip->i_link, ip->i_size,
335 					  sizeof(vip->vii_immed.vi_immed) - 1);
336 		}
337 	} else
338 		init_special_inode(ip, ip->i_mode, old_decode_dev(vip->vii_rdev));
339 
340 	unlock_new_inode(ip);
341 	return ip;
342 }
343 
344 static void vxfs_i_callback(struct rcu_head *head)
345 {
346 	struct inode *inode = container_of(head, struct inode, i_rcu);
347 	kmem_cache_free(vxfs_inode_cachep, inode->i_private);
348 }
349 
350 /**
351  * vxfs_evict_inode - remove inode from main memory
352  * @ip:		inode to discard.
353  *
354  * Description:
355  *  vxfs_evict_inode() is called on the final iput and frees the private
356  *  inode area.
357  */
358 void
359 vxfs_evict_inode(struct inode *ip)
360 {
361 	truncate_inode_pages_final(&ip->i_data);
362 	clear_inode(ip);
363 	call_rcu(&ip->i_rcu, vxfs_i_callback);
364 }
365