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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Super block/filesystem wide operations
  4 *
  5 * Copyright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk> and 
  6 * Michael Callahan <callahan@maths.ox.ac.uk> 
  7 * 
  8 * Rewritten for Linux 2.1.  Peter Braam <braam@cs.cmu.edu>
  9 * Copyright (C) Carnegie Mellon University
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/kernel.h>
 14#include <linux/mm.h>
 15#include <linux/string.h>
 16#include <linux/stat.h>
 17#include <linux/errno.h>
 18#include <linux/unistd.h>
 19#include <linux/mutex.h>
 20#include <linux/spinlock.h>
 21#include <linux/file.h>
 22#include <linux/vfs.h>
 23#include <linux/slab.h>
 24#include <linux/pid_namespace.h>
 25#include <linux/uaccess.h>
 
 26#include <linux/fs.h>
 27#include <linux/vmalloc.h>
 28
 29#include <linux/coda.h>
 30#include <linux/coda_psdev.h>
 31#include "coda_linux.h"
 32#include "coda_cache.h"
 33
 34#include "coda_int.h"
 35
 36/* VFS super_block ops */
 37static void coda_evict_inode(struct inode *);
 38static void coda_put_super(struct super_block *);
 39static int coda_statfs(struct dentry *dentry, struct kstatfs *buf);
 40
 41static struct kmem_cache * coda_inode_cachep;
 42
 43static struct inode *coda_alloc_inode(struct super_block *sb)
 44{
 45	struct coda_inode_info *ei;
 46	ei = kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
 47	if (!ei)
 48		return NULL;
 49	memset(&ei->c_fid, 0, sizeof(struct CodaFid));
 50	ei->c_flags = 0;
 51	ei->c_uid = GLOBAL_ROOT_UID;
 52	ei->c_cached_perm = 0;
 53	spin_lock_init(&ei->c_lock);
 54	return &ei->vfs_inode;
 55}
 56
 57static void coda_i_callback(struct rcu_head *head)
 58{
 59	struct inode *inode = container_of(head, struct inode, i_rcu);
 60	kmem_cache_free(coda_inode_cachep, ITOC(inode));
 61}
 62
 63static void coda_destroy_inode(struct inode *inode)
 64{
 65	call_rcu(&inode->i_rcu, coda_i_callback);
 66}
 67
 68static void init_once(void *foo)
 69{
 70	struct coda_inode_info *ei = (struct coda_inode_info *) foo;
 71
 72	inode_init_once(&ei->vfs_inode);
 73}
 74
 75int __init coda_init_inodecache(void)
 76{
 77	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
 78				sizeof(struct coda_inode_info), 0,
 79				SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
 80				SLAB_ACCOUNT, init_once);
 81	if (coda_inode_cachep == NULL)
 82		return -ENOMEM;
 83	return 0;
 84}
 85
 86void coda_destroy_inodecache(void)
 87{
 88	/*
 89	 * Make sure all delayed rcu free inodes are flushed before we
 90	 * destroy cache.
 91	 */
 92	rcu_barrier();
 93	kmem_cache_destroy(coda_inode_cachep);
 94}
 95
 96static int coda_remount(struct super_block *sb, int *flags, char *data)
 97{
 98	sync_filesystem(sb);
 99	*flags |= SB_NOATIME;
100	return 0;
101}
102
103/* exported operations */
104static const struct super_operations coda_super_operations =
105{
106	.alloc_inode	= coda_alloc_inode,
107	.destroy_inode	= coda_destroy_inode,
108	.evict_inode	= coda_evict_inode,
109	.put_super	= coda_put_super,
110	.statfs		= coda_statfs,
111	.remount_fs	= coda_remount,
112};
113
114static int get_device_index(struct coda_mount_data *data)
115{
116	struct fd f;
117	struct inode *inode;
118	int idx;
119
120	if (data == NULL) {
121		pr_warn("%s: Bad mount data\n", __func__);
122		return -1;
123	}
124
125	if (data->version != CODA_MOUNT_VERSION) {
126		pr_warn("%s: Bad mount version\n", __func__);
127		return -1;
128	}
129
130	f = fdget(data->fd);
131	if (!f.file)
132		goto Ebadf;
133	inode = file_inode(f.file);
134	if (!S_ISCHR(inode->i_mode) || imajor(inode) != CODA_PSDEV_MAJOR) {
135		fdput(f);
136		goto Ebadf;
 
 
 
 
 
137	}
138
139	idx = iminor(inode);
140	fdput(f);
141
142	if (idx < 0 || idx >= MAX_CODADEVS) {
143		pr_warn("%s: Bad minor number\n", __func__);
144		return -1;
145	}
146
147	return idx;
148Ebadf:
149	pr_warn("%s: Bad file\n", __func__);
150	return -1;
151}
152
153static int coda_fill_super(struct super_block *sb, void *data, int silent)
154{
155	struct inode *root = NULL;
156	struct venus_comm *vc;
157	struct CodaFid fid;
158	int error;
159	int idx;
160
161	if (task_active_pid_ns(current) != &init_pid_ns)
162		return -EINVAL;
163
164	idx = get_device_index((struct coda_mount_data *) data);
165
166	/* Ignore errors in data, for backward compatibility */
167	if(idx == -1)
168		idx = 0;
169	
170	pr_info("%s: device index: %i\n", __func__,  idx);
171
172	vc = &coda_comms[idx];
173	mutex_lock(&vc->vc_mutex);
174
175	if (!vc->vc_inuse) {
176		pr_warn("%s: No pseudo device\n", __func__);
177		error = -EINVAL;
178		goto unlock_out;
179	}
180
181	if (vc->vc_sb) {
182		pr_warn("%s: Device already mounted\n", __func__);
183		error = -EBUSY;
184		goto unlock_out;
185	}
186
 
 
 
 
187	vc->vc_sb = sb;
188	mutex_unlock(&vc->vc_mutex);
189
190	sb->s_fs_info = vc;
191	sb->s_flags |= SB_NOATIME;
192	sb->s_blocksize = 4096;	/* XXXXX  what do we put here?? */
193	sb->s_blocksize_bits = 12;
194	sb->s_magic = CODA_SUPER_MAGIC;
195	sb->s_op = &coda_super_operations;
196	sb->s_d_op = &coda_dentry_operations;
197
198	error = super_setup_bdi(sb);
199	if (error)
200		goto error;
201
202	/* get root fid from Venus: this needs the root inode */
203	error = venus_rootfid(sb, &fid);
204	if ( error ) {
205		pr_warn("%s: coda_get_rootfid failed with %d\n",
206			__func__, error);
207		goto error;
208	}
209	pr_info("%s: rootfid is %s\n", __func__, coda_f2s(&fid));
210	
211	/* make root inode */
212        root = coda_cnode_make(&fid, sb);
213        if (IS_ERR(root)) {
214		error = PTR_ERR(root);
215		pr_warn("Failure of coda_cnode_make for root: error %d\n",
216			error);
217		goto error;
218	} 
219
220	pr_info("%s: rootinode is %ld dev %s\n",
221		__func__, root->i_ino, root->i_sb->s_id);
222	sb->s_root = d_make_root(root);
223	if (!sb->s_root) {
224		error = -EINVAL;
225		goto error;
226	}
227	return 0;
228
229error:
230	mutex_lock(&vc->vc_mutex);
 
231	vc->vc_sb = NULL;
232	sb->s_fs_info = NULL;
233unlock_out:
234	mutex_unlock(&vc->vc_mutex);
235	return error;
236}
237
238static void coda_put_super(struct super_block *sb)
239{
240	struct venus_comm *vcp = coda_vcp(sb);
241	mutex_lock(&vcp->vc_mutex);
 
242	vcp->vc_sb = NULL;
243	sb->s_fs_info = NULL;
244	mutex_unlock(&vcp->vc_mutex);
245
246	pr_info("Bye bye.\n");
247}
248
249static void coda_evict_inode(struct inode *inode)
250{
251	truncate_inode_pages_final(&inode->i_data);
252	clear_inode(inode);
253	coda_cache_clear_inode(inode);
254}
255
256int coda_getattr(const struct path *path, struct kstat *stat,
257		 u32 request_mask, unsigned int flags)
258{
259	int err = coda_revalidate_inode(d_inode(path->dentry));
260	if (!err)
261		generic_fillattr(d_inode(path->dentry), stat);
262	return err;
263}
264
265int coda_setattr(struct dentry *de, struct iattr *iattr)
266{
267	struct inode *inode = d_inode(de);
268	struct coda_vattr vattr;
269	int error;
270
271	memset(&vattr, 0, sizeof(vattr)); 
272
273	inode->i_ctime = current_time(inode);
274	coda_iattr_to_vattr(iattr, &vattr);
275	vattr.va_type = C_VNON; /* cannot set type */
276
277	/* Venus is responsible for truncating the container-file!!! */
278	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
279
280	if (!error) {
281	        coda_vattr_to_iattr(inode, &vattr); 
282		coda_cache_clear_inode(inode);
283	}
284	return error;
285}
286
287const struct inode_operations coda_file_inode_operations = {
288	.permission	= coda_permission,
289	.getattr	= coda_getattr,
290	.setattr	= coda_setattr,
291};
292
293static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
294{
295	int error;
296	
297	error = venus_statfs(dentry, buf);
298
299	if (error) {
300		/* fake something like AFS does */
301		buf->f_blocks = 9000000;
302		buf->f_bfree  = 9000000;
303		buf->f_bavail = 9000000;
304		buf->f_files  = 9000000;
305		buf->f_ffree  = 9000000;
306	}
307
308	/* and fill in the rest */
309	buf->f_type = CODA_SUPER_MAGIC;
310	buf->f_bsize = 4096;
311	buf->f_namelen = CODA_MAXNAMLEN;
312
313	return 0; 
314}
315
316/* init_coda: used by filesystems.c to register coda */
317
318static struct dentry *coda_mount(struct file_system_type *fs_type,
319	int flags, const char *dev_name, void *data)
320{
321	return mount_nodev(fs_type, flags, data, coda_fill_super);
322}
323
324struct file_system_type coda_fs_type = {
325	.owner		= THIS_MODULE,
326	.name		= "coda",
327	.mount		= coda_mount,
328	.kill_sb	= kill_anon_super,
329	.fs_flags	= FS_BINARY_MOUNTDATA,
330};
331MODULE_ALIAS_FS("coda");
332
v3.5.6
 
  1/*
  2 * Super block/filesystem wide operations
  3 *
  4 * Copyright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk> and 
  5 * Michael Callahan <callahan@maths.ox.ac.uk> 
  6 * 
  7 * Rewritten for Linux 2.1.  Peter Braam <braam@cs.cmu.edu>
  8 * Copyright (C) Carnegie Mellon University
  9 */
 10
 11#include <linux/module.h>
 12#include <linux/kernel.h>
 13#include <linux/mm.h>
 14#include <linux/string.h>
 15#include <linux/stat.h>
 16#include <linux/errno.h>
 17#include <linux/unistd.h>
 18#include <linux/mutex.h>
 19#include <linux/spinlock.h>
 20#include <linux/file.h>
 21#include <linux/vfs.h>
 22#include <linux/slab.h>
 23
 24#include <asm/uaccess.h>
 25
 26#include <linux/fs.h>
 27#include <linux/vmalloc.h>
 28
 29#include <linux/coda.h>
 30#include <linux/coda_psdev.h>
 31#include "coda_linux.h"
 32#include "coda_cache.h"
 33
 34#include "coda_int.h"
 35
 36/* VFS super_block ops */
 37static void coda_evict_inode(struct inode *);
 38static void coda_put_super(struct super_block *);
 39static int coda_statfs(struct dentry *dentry, struct kstatfs *buf);
 40
 41static struct kmem_cache * coda_inode_cachep;
 42
 43static struct inode *coda_alloc_inode(struct super_block *sb)
 44{
 45	struct coda_inode_info *ei;
 46	ei = kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
 47	if (!ei)
 48		return NULL;
 49	memset(&ei->c_fid, 0, sizeof(struct CodaFid));
 50	ei->c_flags = 0;
 51	ei->c_uid = 0;
 52	ei->c_cached_perm = 0;
 53	spin_lock_init(&ei->c_lock);
 54	return &ei->vfs_inode;
 55}
 56
 57static void coda_i_callback(struct rcu_head *head)
 58{
 59	struct inode *inode = container_of(head, struct inode, i_rcu);
 60	kmem_cache_free(coda_inode_cachep, ITOC(inode));
 61}
 62
 63static void coda_destroy_inode(struct inode *inode)
 64{
 65	call_rcu(&inode->i_rcu, coda_i_callback);
 66}
 67
 68static void init_once(void *foo)
 69{
 70	struct coda_inode_info *ei = (struct coda_inode_info *) foo;
 71
 72	inode_init_once(&ei->vfs_inode);
 73}
 74
 75int coda_init_inodecache(void)
 76{
 77	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
 78				sizeof(struct coda_inode_info),
 79				0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
 80				init_once);
 81	if (coda_inode_cachep == NULL)
 82		return -ENOMEM;
 83	return 0;
 84}
 85
 86void coda_destroy_inodecache(void)
 87{
 
 
 
 
 
 88	kmem_cache_destroy(coda_inode_cachep);
 89}
 90
 91static int coda_remount(struct super_block *sb, int *flags, char *data)
 92{
 93	*flags |= MS_NOATIME;
 
 94	return 0;
 95}
 96
 97/* exported operations */
 98static const struct super_operations coda_super_operations =
 99{
100	.alloc_inode	= coda_alloc_inode,
101	.destroy_inode	= coda_destroy_inode,
102	.evict_inode	= coda_evict_inode,
103	.put_super	= coda_put_super,
104	.statfs		= coda_statfs,
105	.remount_fs	= coda_remount,
106};
107
108static int get_device_index(struct coda_mount_data *data)
109{
110	struct file *file;
111	struct inode *inode;
112	int idx;
113
114	if(data == NULL) {
115		printk("coda_read_super: Bad mount data\n");
116		return -1;
117	}
118
119	if(data->version != CODA_MOUNT_VERSION) {
120		printk("coda_read_super: Bad mount version\n");
121		return -1;
122	}
123
124	file = fget(data->fd);
125	inode = NULL;
126	if(file)
127		inode = file->f_path.dentry->d_inode;
128	
129	if(!inode || !S_ISCHR(inode->i_mode) ||
130	   imajor(inode) != CODA_PSDEV_MAJOR) {
131		if(file)
132			fput(file);
133
134		printk("coda_read_super: Bad file\n");
135		return -1;
136	}
137
138	idx = iminor(inode);
139	fput(file);
140
141	if(idx < 0 || idx >= MAX_CODADEVS) {
142		printk("coda_read_super: Bad minor number\n");
143		return -1;
144	}
145
146	return idx;
 
 
 
147}
148
149static int coda_fill_super(struct super_block *sb, void *data, int silent)
150{
151	struct inode *root = NULL;
152	struct venus_comm *vc;
153	struct CodaFid fid;
154	int error;
155	int idx;
156
 
 
 
157	idx = get_device_index((struct coda_mount_data *) data);
158
159	/* Ignore errors in data, for backward compatibility */
160	if(idx == -1)
161		idx = 0;
162	
163	printk(KERN_INFO "coda_read_super: device index: %i\n", idx);
164
165	vc = &coda_comms[idx];
166	mutex_lock(&vc->vc_mutex);
167
168	if (!vc->vc_inuse) {
169		printk("coda_read_super: No pseudo device\n");
170		error = -EINVAL;
171		goto unlock_out;
172	}
173
174	if (vc->vc_sb) {
175		printk("coda_read_super: Device already mounted\n");
176		error = -EBUSY;
177		goto unlock_out;
178	}
179
180	error = bdi_setup_and_register(&vc->bdi, "coda", BDI_CAP_MAP_COPY);
181	if (error)
182		goto unlock_out;
183
184	vc->vc_sb = sb;
185	mutex_unlock(&vc->vc_mutex);
186
187	sb->s_fs_info = vc;
188	sb->s_flags |= MS_NOATIME;
189	sb->s_blocksize = 4096;	/* XXXXX  what do we put here?? */
190	sb->s_blocksize_bits = 12;
191	sb->s_magic = CODA_SUPER_MAGIC;
192	sb->s_op = &coda_super_operations;
193	sb->s_d_op = &coda_dentry_operations;
194	sb->s_bdi = &vc->bdi;
 
 
 
195
196	/* get root fid from Venus: this needs the root inode */
197	error = venus_rootfid(sb, &fid);
198	if ( error ) {
199	        printk("coda_read_super: coda_get_rootfid failed with %d\n",
200		       error);
201		goto error;
202	}
203	printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
204	
205	/* make root inode */
206        root = coda_cnode_make(&fid, sb);
207        if (IS_ERR(root)) {
208		error = PTR_ERR(root);
209		printk("Failure of coda_cnode_make for root: error %d\n", error);
 
210		goto error;
211	} 
212
213	printk("coda_read_super: rootinode is %ld dev %s\n", 
214	       root->i_ino, root->i_sb->s_id);
215	sb->s_root = d_make_root(root);
216	if (!sb->s_root) {
217		error = -EINVAL;
218		goto error;
219	}
220	return 0;
221
222error:
223	mutex_lock(&vc->vc_mutex);
224	bdi_destroy(&vc->bdi);
225	vc->vc_sb = NULL;
226	sb->s_fs_info = NULL;
227unlock_out:
228	mutex_unlock(&vc->vc_mutex);
229	return error;
230}
231
232static void coda_put_super(struct super_block *sb)
233{
234	struct venus_comm *vcp = coda_vcp(sb);
235	mutex_lock(&vcp->vc_mutex);
236	bdi_destroy(&vcp->bdi);
237	vcp->vc_sb = NULL;
238	sb->s_fs_info = NULL;
239	mutex_unlock(&vcp->vc_mutex);
240
241	printk("Coda: Bye bye.\n");
242}
243
244static void coda_evict_inode(struct inode *inode)
245{
246	truncate_inode_pages(&inode->i_data, 0);
247	clear_inode(inode);
248	coda_cache_clear_inode(inode);
249}
250
251int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 
252{
253	int err = coda_revalidate_inode(dentry);
254	if (!err)
255		generic_fillattr(dentry->d_inode, stat);
256	return err;
257}
258
259int coda_setattr(struct dentry *de, struct iattr *iattr)
260{
261	struct inode *inode = de->d_inode;
262	struct coda_vattr vattr;
263	int error;
264
265	memset(&vattr, 0, sizeof(vattr)); 
266
267	inode->i_ctime = CURRENT_TIME_SEC;
268	coda_iattr_to_vattr(iattr, &vattr);
269	vattr.va_type = C_VNON; /* cannot set type */
270
271	/* Venus is responsible for truncating the container-file!!! */
272	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
273
274	if (!error) {
275	        coda_vattr_to_iattr(inode, &vattr); 
276		coda_cache_clear_inode(inode);
277	}
278	return error;
279}
280
281const struct inode_operations coda_file_inode_operations = {
282	.permission	= coda_permission,
283	.getattr	= coda_getattr,
284	.setattr	= coda_setattr,
285};
286
287static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
288{
289	int error;
290	
291	error = venus_statfs(dentry, buf);
292
293	if (error) {
294		/* fake something like AFS does */
295		buf->f_blocks = 9000000;
296		buf->f_bfree  = 9000000;
297		buf->f_bavail = 9000000;
298		buf->f_files  = 9000000;
299		buf->f_ffree  = 9000000;
300	}
301
302	/* and fill in the rest */
303	buf->f_type = CODA_SUPER_MAGIC;
304	buf->f_bsize = 4096;
305	buf->f_namelen = CODA_MAXNAMLEN;
306
307	return 0; 
308}
309
310/* init_coda: used by filesystems.c to register coda */
311
312static struct dentry *coda_mount(struct file_system_type *fs_type,
313	int flags, const char *dev_name, void *data)
314{
315	return mount_nodev(fs_type, flags, data, coda_fill_super);
316}
317
318struct file_system_type coda_fs_type = {
319	.owner		= THIS_MODULE,
320	.name		= "coda",
321	.mount		= coda_mount,
322	.kill_sb	= kill_anon_super,
323	.fs_flags	= FS_BINARY_MOUNTDATA,
324};
 
325