[mirror_ubuntu-artful-kernel.git] / fs / coda / inode.c

/*
 * Super block/filesystem wide operations
 *
 * Copyright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk> and 
 * Michael Callahan <callahan@maths.ox.ac.uk> 
 * 
 * Rewritten for Linux 2.1.  Peter Braam <braam@cs.cmu.edu>
 * Copyright (C) Carnegie Mellon University
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/file.h>
#include <linux/vfs.h>
#include <linux/slab.h>
#include <linux/pid_namespace.h>
#include <linux/uaccess.h>
#include <linux/fs.h>
#include <linux/vmalloc.h>

#include <linux/coda.h>
#include <linux/coda_psdev.h>
#include "coda_linux.h"
#include "coda_cache.h"

#include "coda_int.h"

/* VFS super_block ops */
static void coda_evict_inode(struct inode *);
static void coda_put_super(struct super_block *);
static int coda_statfs(struct dentry *dentry, struct kstatfs *buf);

static struct kmem_cache * coda_inode_cachep;

static struct inode *coda_alloc_inode(struct super_block *sb)
{
	struct coda_inode_info *ei;
	ei = kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	memset(&ei->c_fid, 0, sizeof(struct CodaFid));
	ei->c_flags = 0;
	ei->c_uid = GLOBAL_ROOT_UID;
	ei->c_cached_perm = 0;
	spin_lock_init(&ei->c_lock);
	return &ei->vfs_inode;
}

static void coda_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	kmem_cache_free(coda_inode_cachep, ITOC(inode));
}

static void coda_destroy_inode(struct inode *inode)
{
	call_rcu(&inode->i_rcu, coda_i_callback);
}

static void init_once(void *foo)
{
	struct coda_inode_info *ei = (struct coda_inode_info *) foo;

	inode_init_once(&ei->vfs_inode);
}

int __init coda_init_inodecache(void)
{
	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
				sizeof(struct coda_inode_info), 0,
				SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
				SLAB_ACCOUNT, init_once);
	if (coda_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

void coda_destroy_inodecache(void)
{
	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
	kmem_cache_destroy(coda_inode_cachep);
}

static int coda_remount(struct super_block *sb, int *flags, char *data)
{
	sync_filesystem(sb);
	*flags |= MS_NOATIME;
	return 0;
}

/* exported operations */
static const struct super_operations coda_super_operations =
{
	.alloc_inode	= coda_alloc_inode,
	.destroy_inode	= coda_destroy_inode,
	.evict_inode	= coda_evict_inode,
	.put_super	= coda_put_super,
	.statfs		= coda_statfs,
	.remount_fs	= coda_remount,
};

static int get_device_index(struct coda_mount_data *data)
{
	struct fd f;
	struct inode *inode;
	int idx;

	if (data == NULL) {
		pr_warn("%s: Bad mount data\n", __func__);
		return -1;
	}

	if (data->version != CODA_MOUNT_VERSION) {
		pr_warn("%s: Bad mount version\n", __func__);
		return -1;
	}

	f = fdget(data->fd);
	if (!f.file)
		goto Ebadf;
	inode = file_inode(f.file);
	if (!S_ISCHR(inode->i_mode) || imajor(inode) != CODA_PSDEV_MAJOR) {
		fdput(f);
		goto Ebadf;
	}

	idx = iminor(inode);
	fdput(f);

	if (idx < 0 || idx >= MAX_CODADEVS) {
		pr_warn("%s: Bad minor number\n", __func__);
		return -1;
	}

	return idx;
Ebadf:
	pr_warn("%s: Bad file\n", __func__);
	return -1;
}

static int coda_fill_super(struct super_block *sb, void *data, int silent)
{
	struct inode *root = NULL;
	struct venus_comm *vc;
	struct CodaFid fid;
	int error;
	int idx;

	if (task_active_pid_ns(current) != &init_pid_ns)
		return -EINVAL;

	idx = get_device_index((struct coda_mount_data *) data);

	/* Ignore errors in data, for backward compatibility */
	if(idx == -1)
		idx = 0;
	
	pr_info("%s: device index: %i\n", __func__,  idx);

	vc = &coda_comms[idx];
	mutex_lock(&vc->vc_mutex);

	if (!vc->vc_inuse) {
		pr_warn("%s: No pseudo device\n", __func__);
		error = -EINVAL;
		goto unlock_out;
	}

	if (vc->vc_sb) {
		pr_warn("%s: Device already mounted\n", __func__);
		error = -EBUSY;
		goto unlock_out;
	}

	vc->vc_sb = sb;
	mutex_unlock(&vc->vc_mutex);

	sb->s_fs_info = vc;
	sb->s_flags |= MS_NOATIME;
	sb->s_blocksize = 4096;	/* XXXXX  what do we put here?? */
	sb->s_blocksize_bits = 12;
	sb->s_magic = CODA_SUPER_MAGIC;
	sb->s_op = &coda_super_operations;
	sb->s_d_op = &coda_dentry_operations;

	error = super_setup_bdi(sb);
	if (error)
		goto error;

	/* get root fid from Venus: this needs the root inode */
	error = venus_rootfid(sb, &fid);
	if ( error ) {
		pr_warn("%s: coda_get_rootfid failed with %d\n",
			__func__, error);
		goto error;
	}
	pr_info("%s: rootfid is %s\n", __func__, coda_f2s(&fid));
	
	/* make root inode */
        root = coda_cnode_make(&fid, sb);
        if (IS_ERR(root)) {
		error = PTR_ERR(root);
		pr_warn("Failure of coda_cnode_make for root: error %d\n",
			error);
		goto error;
	} 

	pr_info("%s: rootinode is %ld dev %s\n",
		__func__, root->i_ino, root->i_sb->s_id);
	sb->s_root = d_make_root(root);
	if (!sb->s_root) {
		error = -EINVAL;
		goto error;
	}
	return 0;

error:
	mutex_lock(&vc->vc_mutex);
	vc->vc_sb = NULL;
	sb->s_fs_info = NULL;
unlock_out:
	mutex_unlock(&vc->vc_mutex);
	return error;
}

static void coda_put_super(struct super_block *sb)
{
	struct venus_comm *vcp = coda_vcp(sb);
	mutex_lock(&vcp->vc_mutex);
	vcp->vc_sb = NULL;
	sb->s_fs_info = NULL;
	mutex_unlock(&vcp->vc_mutex);

	pr_info("Bye bye.\n");
}

static void coda_evict_inode(struct inode *inode)
{
	truncate_inode_pages_final(&inode->i_data);
	clear_inode(inode);
	coda_cache_clear_inode(inode);
}

int coda_getattr(const struct path *path, struct kstat *stat,
		 u32 request_mask, unsigned int flags)
{
	int err = coda_revalidate_inode(d_inode(path->dentry));
	if (!err)
		generic_fillattr(d_inode(path->dentry), stat);
	return err;
}

int coda_setattr(struct dentry *de, struct iattr *iattr)
{
	struct inode *inode = d_inode(de);
	struct coda_vattr vattr;
	int error;

	memset(&vattr, 0, sizeof(vattr)); 

	inode->i_ctime = current_time(inode);
	coda_iattr_to_vattr(iattr, &vattr);
	vattr.va_type = C_VNON; /* cannot set type */

	/* Venus is responsible for truncating the container-file!!! */
	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);

	if (!error) {
	        coda_vattr_to_iattr(inode, &vattr); 
		coda_cache_clear_inode(inode);
	}
	return error;
}

const struct inode_operations coda_file_inode_operations = {
	.permission	= coda_permission,
	.getattr	= coda_getattr,
	.setattr	= coda_setattr,
};

static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	int error;
	
	error = venus_statfs(dentry, buf);

	if (error) {
		/* fake something like AFS does */
		buf->f_blocks = 9000000;
		buf->f_bfree  = 9000000;
		buf->f_bavail = 9000000;
		buf->f_files  = 9000000;
		buf->f_ffree  = 9000000;
	}

	/* and fill in the rest */
	buf->f_type = CODA_SUPER_MAGIC;
	buf->f_bsize = 4096;
	buf->f_namelen = CODA_MAXNAMLEN;

	return 0; 
}

/* init_coda: used by filesystems.c to register coda */

static struct dentry *coda_mount(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return mount_nodev(fs_type, flags, data, coda_fill_super);
}

struct file_system_type coda_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "coda",
	.mount		= coda_mount,
	.kill_sb	= kill_anon_super,
	.fs_flags	= FS_BINARY_MOUNTDATA,
};
MODULE_ALIAS_FS("coda");
Commit	Line	Data
1da177e4 LT	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>
da47c19e	18	#include <linux/mutex.h>
b5ce1d83	19	#include <linux/spinlock.h>
1da177e4 LT	20	#include <linux/file.h>
1da177e4 LT	21	#include <linux/vfs.h>
5a0e3ad6	22	#include <linux/slab.h>
9fd973e0	23	#include <linux/pid_namespace.h>
834b46c3	24	#include <linux/uaccess.h>
1da177e4 LT	25	#include <linux/fs.h>
	26	#include <linux/vmalloc.h>
	27
	28	#include <linux/coda.h>
1da177e4	29	#include <linux/coda_psdev.h>
31a203df AV	30	#include "coda_linux.h"
31a203df AV	31	#include "coda_cache.h"
1da177e4	32
c98d8cfb AB	33	#include "coda_int.h"
c98d8cfb AB	34
1da177e4	35	/* VFS super_block ops */
b57922d9	36	static void coda_evict_inode(struct inode *);
1da177e4	37	static void coda_put_super(struct super_block *);
726c3342	38	static int coda_statfs(struct dentry dentry, struct kstatfs buf);
1da177e4	39
e18b890b	40	static struct kmem_cache * coda_inode_cachep;
1da177e4 LT	41
	42	static struct inode coda_alloc_inode(struct super_block sb)
	43	{
	44	struct coda_inode_info *ei;
747fecab	45	ei = kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
1da177e4 LT	46	if (!ei)
	47	return NULL;
	48	memset(&ei->c_fid, 0, sizeof(struct CodaFid));
	49	ei->c_flags = 0;
17499e33	50	ei->c_uid = GLOBAL_ROOT_UID;
1da177e4	51	ei->c_cached_perm = 0;
b5ce1d83	52	spin_lock_init(&ei->c_lock);
1da177e4 LT	53	return &ei->vfs_inode;
	54	}
	55
fa0d7e3d	56	static void coda_i_callback(struct rcu_head *head)
1da177e4	57	{
fa0d7e3d	58	struct inode *inode = container_of(head, struct inode, i_rcu);
1da177e4 LT	59	kmem_cache_free(coda_inode_cachep, ITOC(inode));
	60	}
	61
fa0d7e3d NP	62	static void coda_destroy_inode(struct inode *inode)
	63	{
	64	call_rcu(&inode->i_rcu, coda_i_callback);
	65	}
	66
51cc5068	67	static void init_once(void *foo)
1da177e4 LT	68	{
	69	struct coda_inode_info ei = (struct coda_inode_info ) foo;
	70
a35afb83	71	inode_init_once(&ei->vfs_inode);
1da177e4	72	}
20c2df83	73
5f356fd4	74	int __init coda_init_inodecache(void)
1da177e4 LT	75	{
1da177e4 LT	76	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
5d097056 VD	77	sizeof(struct coda_inode_info), 0,
	78	SLAB_RECLAIM_ACCOUNT\|SLAB_MEM_SPREAD\|
	79	SLAB_ACCOUNT, init_once);
1da177e4 LT	80	if (coda_inode_cachep == NULL)
	81	return -ENOMEM;
	82	return 0;
	83	}
	84
	85	void coda_destroy_inodecache(void)
	86	{
8c0a8537 KS	87	/*
	88	* Make sure all delayed rcu free inodes are flushed before we
	89	* destroy cache.
	90	*/
	91	rcu_barrier();
1a1d92c1	92	kmem_cache_destroy(coda_inode_cachep);
1da177e4 LT	93	}
	94
	95	static int coda_remount(struct super_block sb, int flags, char *data)
	96	{
02b9984d	97	sync_filesystem(sb);
fac1f0e3	98	*flags \|= MS_NOATIME;
1da177e4 LT	99	return 0;
	100	}
	101
	102	/* exported operations */
ee9b6d61	103	static const struct super_operations coda_super_operations =
1da177e4 LT	104	{
	105	.alloc_inode = coda_alloc_inode,
	106	.destroy_inode = coda_destroy_inode,
b57922d9	107	.evict_inode = coda_evict_inode,
1da177e4 LT	108	.put_super = coda_put_super,
	109	.statfs = coda_statfs,
	110	.remount_fs = coda_remount,
	111	};
	112
	113	static int get_device_index(struct coda_mount_data *data)
	114	{
2903ff01	115	struct fd f;
1da177e4	116	struct inode *inode;
2903ff01	117	int idx;
1da177e4	118
78f7d75e	119	if (data == NULL) {
6d6bd94f	120	pr_warn("%s: Bad mount data\n", __func__);
1da177e4 LT	121	return -1;
	122	}
	123
78f7d75e	124	if (data->version != CODA_MOUNT_VERSION) {
6d6bd94f	125	pr_warn("%s: Bad mount version\n", __func__);
1da177e4 LT	126	return -1;
	127	}
	128
2903ff01 AV	129	f = fdget(data->fd);
2903ff01 AV	130	if (!f.file)
78f7d75e	131	goto Ebadf;
496ad9aa	132	inode = file_inode(f.file);
78f7d75e	133	if (!S_ISCHR(inode->i_mode) \|\| imajor(inode) != CODA_PSDEV_MAJOR) {
2903ff01	134	fdput(f);
78f7d75e	135	goto Ebadf;
1da177e4 LT	136	}
	137
	138	idx = iminor(inode);
2903ff01	139	fdput(f);
1da177e4	140
78f7d75e	141	if (idx < 0 \|\| idx >= MAX_CODADEVS) {
6d6bd94f	142	pr_warn("%s: Bad minor number\n", __func__);
1da177e4 LT	143	return -1;
	144	}
	145
	146	return idx;
78f7d75e	147	Ebadf:
6d6bd94f	148	pr_warn("%s: Bad file\n", __func__);
78f7d75e	149	return -1;
1da177e4 LT	150	}
	151
	152	static int coda_fill_super(struct super_block sb, void data, int silent)
	153	{
a1b0aa87	154	struct inode *root = NULL;
da47c19e	155	struct venus_comm *vc;
1da177e4	156	struct CodaFid fid;
a1b0aa87	157	int error;
1da177e4 LT	158	int idx;
1da177e4 LT	159
9fd973e0 EB	160	if (task_active_pid_ns(current) != &init_pid_ns)
	161	return -EINVAL;
	162
1da177e4 LT	163	idx = get_device_index((struct coda_mount_data *) data);
	164
	165	/* Ignore errors in data, for backward compatibility */
	166	if(idx == -1)
	167	idx = 0;
	168
6d6bd94f	169	pr_info("%s: device index: %i\n", __func__, idx);
1da177e4 LT	170
1da177e4 LT	171	vc = &coda_comms[idx];
da47c19e	172	mutex_lock(&vc->vc_mutex);
f7cc02b8	173
1da177e4	174	if (!vc->vc_inuse) {
6d6bd94f	175	pr_warn("%s: No pseudo device\n", __func__);
f7cc02b8 YA	176	error = -EINVAL;
f7cc02b8 YA	177	goto unlock_out;
1da177e4 LT	178	}
1da177e4 LT	179
f7cc02b8	180	if (vc->vc_sb) {
6d6bd94f	181	pr_warn("%s: Device already mounted\n", __func__);
f7cc02b8 YA	182	error = -EBUSY;
f7cc02b8 YA	183	goto unlock_out;
1da177e4 LT	184	}
1da177e4 LT	185
1da177e4	186	vc->vc_sb = sb;
da47c19e	187	mutex_unlock(&vc->vc_mutex);
1da177e4	188
a1b0aa87	189	sb->s_fs_info = vc;
fac1f0e3 JH	190	sb->s_flags \|= MS_NOATIME;
	191	sb->s_blocksize = 4096; /* XXXXX what do we put here?? */
	192	sb->s_blocksize_bits = 12;
	193	sb->s_magic = CODA_SUPER_MAGIC;
	194	sb->s_op = &coda_super_operations;
9501e4c4	195	sb->s_d_op = &coda_dentry_operations;
a5695a79 JK	196
	197	error = super_setup_bdi(sb);
	198	if (error)
	199	goto error;
1da177e4 LT	200
	201	/* get root fid from Venus: this needs the root inode */
	202	error = venus_rootfid(sb, &fid);
	203	if ( error ) {
6d6bd94f FF	204	pr_warn("%s: coda_get_rootfid failed with %d\n",
6d6bd94f FF	205	__func__, error);
1da177e4 LT	206	goto error;
1da177e4 LT	207	}
6d6bd94f	208	pr_info("%s: rootfid is %s\n", __func__, coda_f2s(&fid));
1da177e4 LT	209
1da177e4 LT	210	/* make root inode */
f4947fbc AV	211	root = coda_cnode_make(&fid, sb);
	212	if (IS_ERR(root)) {
	213	error = PTR_ERR(root);
d9b4b319 FF	214	pr_warn("Failure of coda_cnode_make for root: error %d\n",
d9b4b319 FF	215	error);
f4947fbc	216	goto error;
1da177e4 LT	217	}
1da177e4 LT	218
6d6bd94f FF	219	pr_info("%s: rootinode is %ld dev %s\n",
6d6bd94f FF	220	__func__, root->i_ino, root->i_sb->s_id);
48fde701	221	sb->s_root = d_make_root(root);
f7cc02b8 YA	222	if (!sb->s_root) {
f7cc02b8 YA	223	error = -EINVAL;
1da177e4	224	goto error;
f7cc02b8	225	}
db719222	226	return 0;
1da177e4	227
f7cc02b8	228	error:
da47c19e	229	mutex_lock(&vc->vc_mutex);
f7cc02b8 YA	230	vc->vc_sb = NULL;
	231	sb->s_fs_info = NULL;
	232	unlock_out:
da47c19e	233	mutex_unlock(&vc->vc_mutex);
f7cc02b8	234	return error;
1da177e4 LT	235	}
	236
	237	static void coda_put_super(struct super_block *sb)
	238	{
da47c19e YA	239	struct venus_comm *vcp = coda_vcp(sb);
da47c19e YA	240	mutex_lock(&vcp->vc_mutex);
da47c19e	241	vcp->vc_sb = NULL;
a1b0aa87	242	sb->s_fs_info = NULL;
da47c19e	243	mutex_unlock(&vcp->vc_mutex);
1da177e4	244
f38cfb25	245	pr_info("Bye bye.\n");
1da177e4 LT	246	}
1da177e4 LT	247
b57922d9	248	static void coda_evict_inode(struct inode *inode)
1da177e4	249	{
91b0abe3	250	truncate_inode_pages_final(&inode->i_data);
dbd5768f	251	clear_inode(inode);
1da177e4 LT	252	coda_cache_clear_inode(inode);
	253	}
	254
a528d35e DH	255	int coda_getattr(const struct path path, struct kstat stat,
a528d35e DH	256	u32 request_mask, unsigned int flags)
1da177e4	257	{
a528d35e	258	int err = coda_revalidate_inode(d_inode(path->dentry));
1da177e4	259	if (!err)
a528d35e	260	generic_fillattr(d_inode(path->dentry), stat);
1da177e4 LT	261	return err;
	262	}
	263
	264	int coda_setattr(struct dentry de, struct iattr iattr)
	265	{
2b0143b5	266	struct inode *inode = d_inode(de);
1da177e4 LT	267	struct coda_vattr vattr;
	268	int error;
	269
1da177e4 LT	270	memset(&vattr, 0, sizeof(vattr));
1da177e4 LT	271
02027d42	272	inode->i_ctime = current_time(inode);
1da177e4 LT	273	coda_iattr_to_vattr(iattr, &vattr);
	274	vattr.va_type = C_VNON; /* cannot set type */
	275
	276	/* Venus is responsible for truncating the container-file!!! */
	277	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
	278
f7cc02b8	279	if (!error) {
1da177e4 LT	280	coda_vattr_to_iattr(inode, &vattr);
	281	coda_cache_clear_inode(inode);
	282	}
1da177e4 LT	283	return error;
	284	}
	285
754661f1	286	const struct inode_operations coda_file_inode_operations = {
1da177e4 LT	287	.permission = coda_permission,
	288	.getattr = coda_getattr,
	289	.setattr = coda_setattr,
	290	};
	291
726c3342	292	static int coda_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4 LT	293	{
	294	int error;
	295
726c3342	296	error = venus_statfs(dentry, buf);
1da177e4	297
1da177e4 LT	298	if (error) {
	299	/* fake something like AFS does */
	300	buf->f_blocks = 9000000;
	301	buf->f_bfree = 9000000;
	302	buf->f_bavail = 9000000;
	303	buf->f_files = 9000000;
	304	buf->f_ffree = 9000000;
	305	}
	306
	307	/* and fill in the rest */
	308	buf->f_type = CODA_SUPER_MAGIC;
fac1f0e3	309	buf->f_bsize = 4096;
1da177e4 LT	310	buf->f_namelen = CODA_MAXNAMLEN;
	311
	312	return 0;
	313	}
	314
	315	/* init_coda: used by filesystems.c to register coda */
	316
3c26ff6e AV	317	static struct dentry coda_mount(struct file_system_type fs_type,
3c26ff6e AV	318	int flags, const char dev_name, void data)
1da177e4	319	{
3c26ff6e	320	return mount_nodev(fs_type, flags, data, coda_fill_super);
1da177e4 LT	321	}
	322
	323	struct file_system_type coda_fs_type = {
	324	.owner = THIS_MODULE,
	325	.name = "coda",
3c26ff6e	326	.mount = coda_mount,
1da177e4 LT	327	.kill_sb = kill_anon_super,
	328	.fs_flags = FS_BINARY_MOUNTDATA,
	329	};
7f78e035	330	MODULE_ALIAS_FS("coda");
1da177e4	331