4 * Copyright (C) 1998 Peter J. Braam
5 * Copyright (C) 2000 Stelias Computing, Inc.
6 * Copyright (C) 2000 Red Hat, Inc.
7 * Copyright (C) 2000 Mountain View Data, Inc.
9 * Author: Peter J. Braam <braam@mountainviewdata.com>
11 #define DEBUG_SUBSYSTEM S_SM
13 #include <linux/config.h>
14 #include <linux/module.h>
15 #include <linux/kmod.h>
16 #include <linux/init.h>
18 #include <linux/string.h>
20 #include <linux/utime.h>
21 #include <linux/file.h>
22 #include <linux/slab.h>
23 #include <linux/loop.h>
24 #include <linux/errno.h>
25 #include "smfs_internal.h"
27 /* Find the options for the clone. These consist of a cache device
28 and an index in the snaptable associated with that device.
30 static char *smfs_options(char *options, char **devstr, char **namestr)
32 struct option *opt_value = NULL;
35 while (!(get_opt(&opt_value, &pos))) {
36 if (!strcmp(opt_value->opt, "dev")) {
38 *devstr = opt_value->value;
39 } else if (!strcmp(opt_value->opt, "type")) {
41 *namestr = opt_value->value;
49 static int set_loop_fd(char *dev_path, char *loop_dev)
51 struct loop_info loopinfo;
53 struct dentry *dentry;
54 struct block_device_operations *bd_ops;
56 int fd = 0, error = 0;
60 if (!fd) RETURN(-EINVAL);
62 filp = filp_open(dev_path, FMODE_WRITE, 0);
63 if (!filp || !S_ISREG(filp->f_dentry->d_inode->i_mode))
68 if (path_init(loop_dev, LOOKUP_FOLLOW, &nd)) {
69 error = path_walk(loop_dev, &nd);
72 filp_close(filp, current->files);
77 filp_close(filp, current->files);
81 bd_ops = get_blkfops(LOOP_MAJOR);
83 error = bd_ops->ioctl(dentry->d_inode, filp, LOOP_SET_FD,
87 filp_close(filp, current->files);
90 memset(&loopinfo, 0, sizeof(struct loop_info));
92 error = bd_ops->ioctl(dentry->d_inode, filp, LOOP_SET_STATUS,
93 (unsigned long)(&loopinfo));
98 #define SIZE(a) (sizeof(a)/sizeof(a[0]))
99 static char *find_unused_and_set_loop_device(char *dev_path)
101 char *loop_formats[] = { "/dev/loop/%d", "/dev/loop%d"};
102 struct loop_info loopinfo;
104 struct dentry *dentry;
108 for (j = 0; j < SIZE(loop_formats); j++) {
109 SM_ALLOC(dev, strlen(loop_formats[i]) + 1);
110 for(i = 0; i < 256; i++) {
111 struct block_device_operations *bd_ops;
113 sprintf(dev, loop_formats[j], i);
115 if (path_init(dev, LOOKUP_FOLLOW, &nd)) {
116 error = path_walk(dev, &nd);
117 if (error && error != -ENOENT) {
119 SM_FREE(dev, strlen(loop_formats[i]) + 1);
123 SM_FREE(dev, strlen(loop_formats[i]) + 1);
127 bd_ops = get_blkfops(LOOP_MAJOR);
128 error = bd_ops->ioctl(dentry->d_inode, NULL, LOOP_GET_STATUS,
129 (unsigned long)&loopinfo);
132 if (error == -ENXIO) {
133 /*find unused loop and set dev_path to loopdev*/
134 error = set_loop_fd(dev_path, dev);
136 SM_FREE(dev, strlen(loop_formats[i]) + 1);
139 return dev;/* probably free */
142 SM_FREE(dev, strlen(loop_formats[i]) + 1);
147 #define MAX_LOOP_DEVICES 256
148 static char *parse_path2dev(struct super_block *sb, char *dev_path)
150 struct dentry *dentry;
155 if (path_init(dev_path, LOOKUP_FOLLOW, &nd)) {
156 error = path_walk(dev_path, &nd);
166 if (!dentry->d_inode || is_bad_inode(dentry->d_inode) ||
167 (!S_ISBLK(dentry->d_inode->i_mode) &&
168 !S_ISREG(dentry->d_inode->i_mode))){
173 if (S_ISREG(dentry->d_inode->i_mode)) {
174 name = find_unused_and_set_loop_device(dev_path);
178 SM_ALLOC(name, strlen(dev_path) + 1);
179 memcpy(name, dev_path, strlen(dev_path) + 1);
182 void duplicate_sb(struct super_block *csb,
183 struct super_block *sb)
185 sb->s_blocksize = csb->s_blocksize;
186 sb->s_magic = csb->s_magic;
187 sb->s_blocksize_bits = csb->s_blocksize_bits;
188 sb->s_maxbytes = csb->s_maxbytes;
190 extern struct super_operations smfs_super_ops;
192 static int sm_mount_cache(struct super_block *sb,
196 struct vfsmount *mnt;
197 struct smfs_super_info *smb;
198 char *dev_name = NULL;
202 dev_name = parse_path2dev(sb, devstr);
204 GOTO(err_out, err = -ENOMEM);
206 if (!(page = __get_free_page(GFP_KERNEL))) {
207 GOTO(err_out, err = -ENOMEM);
209 memset((void *)page, 0, PAGE_SIZE);
210 sprintf((char *)page, "iopen_nopriv");
212 mnt = do_kern_mount(typestr, 0, dev_name, (void *)page);
216 CERROR("do_kern_mount failed: rc = %ld\n", PTR_ERR(mnt));
217 GOTO(err_out, err = PTR_ERR(mnt));
220 smb->smsi_sb = mnt->mnt_sb;
223 duplicate_sb(mnt->mnt_sb, sb);
224 sm_set_sb_ops(mnt->mnt_sb, sb);
227 SM_FREE(dev_name, strlen(dev_name) + 2);
231 static int sm_umount_cache(struct super_block *sb)
233 struct smfs_super_info *smb = S2SMI(sb);
235 mntput(smb->smsi_mnt);
239 void smfs_put_super(struct super_block *sb)
248 struct super_block *sb,
252 struct inode *root_inode = NULL;
253 char *devstr = NULL, *typestr = NULL;
260 CDEBUG(D_SUPER, "mount opts: %s\n", data ? (char *)data : "(none)");
263 /* read and validate options */
264 cache_data = smfs_options(data, &devstr, &typestr);
266 CERROR("invalid mount option %s\n", (char*)data);
267 GOTO(out_err, err=-EINVAL);
269 if (!typestr || !devstr) {
270 CERROR("mount options name and dev mandatory\n");
271 GOTO(out_err, err=-EINVAL);
274 err = sm_mount_cache(sb, devstr, typestr);
276 CERROR("Can not mount %s as %s\n", devstr, typestr);
279 dget(S2CSB(sb)->s_root);
280 root_ino = S2CSB(sb)->s_root->d_inode->i_ino;
281 root_inode = iget(sb, root_ino);
283 CDEBUG(D_SUPER, "readinode %p, root ino %ld, root inode at %p\n",
284 sb->s_op->read_inode, root_ino, root_inode);
286 sb->s_root = d_alloc_root(root_inode);
289 GOTO(out_err, err=-EINVAL);
292 CDEBUG(D_SUPER, "sb %lx, &sb->u.generic_sbp: %lx\n",
293 (ulong) sb, (ulong) &sb->u.generic_sbp);
302 static DECLARE_FSTYPE(smfs_type, "smfs", smfs_read_super, 0);
308 err = register_filesystem(&smfs_type);
310 CERROR("smfs: failed in register Storage Management filesystem!\n");
316 int cleanup_smfs(void)
321 err = unregister_filesystem(&smfs_type);
323 CERROR("smfs: failed to unregister Storage Management filesystem!\n");
325 cleanup_smfs_cache();