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

// SPDX-License-Identifier: GPL-2.0
/*
 * 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 |= SB_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 |= SB_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
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	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>
da47c19e	19	#include <linux/mutex.h>
b5ce1d83	20	#include <linux/spinlock.h>
1da177e4 LT	21	#include <linux/file.h>
1da177e4 LT	22	#include <linux/vfs.h>
5a0e3ad6	23	#include <linux/slab.h>
9fd973e0	24	#include <linux/pid_namespace.h>
834b46c3	25	#include <linux/uaccess.h>
1da177e4 LT	26	#include <linux/fs.h>
	27	#include <linux/vmalloc.h>
	28
	29	#include <linux/coda.h>
1da177e4	30	#include <linux/coda_psdev.h>
31a203df AV	31	#include "coda_linux.h"
31a203df AV	32	#include "coda_cache.h"
1da177e4	33
c98d8cfb AB	34	#include "coda_int.h"
c98d8cfb AB	35
1da177e4	36	/* VFS super_block ops */
b57922d9	37	static void coda_evict_inode(struct inode *);
1da177e4	38	static void coda_put_super(struct super_block *);
726c3342	39	static int coda_statfs(struct dentry dentry, struct kstatfs buf);
1da177e4	40
e18b890b	41	static struct kmem_cache * coda_inode_cachep;
1da177e4 LT	42
	43	static struct inode coda_alloc_inode(struct super_block sb)
	44	{
	45	struct coda_inode_info *ei;
747fecab	46	ei = kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
1da177e4 LT	47	if (!ei)
	48	return NULL;
	49	memset(&ei->c_fid, 0, sizeof(struct CodaFid));
	50	ei->c_flags = 0;
17499e33	51	ei->c_uid = GLOBAL_ROOT_UID;
1da177e4	52	ei->c_cached_perm = 0;
b5ce1d83	53	spin_lock_init(&ei->c_lock);
1da177e4 LT	54	return &ei->vfs_inode;
	55	}
	56
fa0d7e3d	57	static void coda_i_callback(struct rcu_head *head)
1da177e4	58	{
fa0d7e3d	59	struct inode *inode = container_of(head, struct inode, i_rcu);
1da177e4 LT	60	kmem_cache_free(coda_inode_cachep, ITOC(inode));
	61	}
	62
fa0d7e3d NP	63	static void coda_destroy_inode(struct inode *inode)
	64	{
	65	call_rcu(&inode->i_rcu, coda_i_callback);
	66	}
	67
51cc5068	68	static void init_once(void *foo)
1da177e4 LT	69	{
	70	struct coda_inode_info ei = (struct coda_inode_info ) foo;
	71
a35afb83	72	inode_init_once(&ei->vfs_inode);
1da177e4	73	}
20c2df83	74
5f356fd4	75	int __init coda_init_inodecache(void)
1da177e4 LT	76	{
1da177e4 LT	77	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
5d097056 VD	78	sizeof(struct coda_inode_info), 0,
	79	SLAB_RECLAIM_ACCOUNT\|SLAB_MEM_SPREAD\|
	80	SLAB_ACCOUNT, init_once);
1da177e4 LT	81	if (coda_inode_cachep == NULL)
	82	return -ENOMEM;
	83	return 0;
	84	}
	85
	86	void coda_destroy_inodecache(void)
	87	{
8c0a8537 KS	88	/*
	89	* Make sure all delayed rcu free inodes are flushed before we
	90	* destroy cache.
	91	*/
	92	rcu_barrier();
1a1d92c1	93	kmem_cache_destroy(coda_inode_cachep);
1da177e4 LT	94	}
	95
	96	static int coda_remount(struct super_block sb, int flags, char *data)
	97	{
02b9984d	98	sync_filesystem(sb);
1751e8a6	99	*flags \|= SB_NOATIME;
1da177e4 LT	100	return 0;
	101	}
	102
	103	/* exported operations */
ee9b6d61	104	static const struct super_operations coda_super_operations =
1da177e4 LT	105	{
	106	.alloc_inode = coda_alloc_inode,
	107	.destroy_inode = coda_destroy_inode,
b57922d9	108	.evict_inode = coda_evict_inode,
1da177e4 LT	109	.put_super = coda_put_super,
	110	.statfs = coda_statfs,
	111	.remount_fs = coda_remount,
	112	};
	113
	114	static int get_device_index(struct coda_mount_data *data)
	115	{
2903ff01	116	struct fd f;
1da177e4	117	struct inode *inode;
2903ff01	118	int idx;
1da177e4	119
78f7d75e	120	if (data == NULL) {
6d6bd94f	121	pr_warn("%s: Bad mount data\n", __func__);
1da177e4 LT	122	return -1;
	123	}
	124
78f7d75e	125	if (data->version != CODA_MOUNT_VERSION) {
6d6bd94f	126	pr_warn("%s: Bad mount version\n", __func__);
1da177e4 LT	127	return -1;
	128	}
	129
2903ff01 AV	130	f = fdget(data->fd);
2903ff01 AV	131	if (!f.file)
78f7d75e	132	goto Ebadf;
496ad9aa	133	inode = file_inode(f.file);
78f7d75e	134	if (!S_ISCHR(inode->i_mode) \|\| imajor(inode) != CODA_PSDEV_MAJOR) {
2903ff01	135	fdput(f);
78f7d75e	136	goto Ebadf;
1da177e4 LT	137	}
	138
	139	idx = iminor(inode);
2903ff01	140	fdput(f);
1da177e4	141
78f7d75e	142	if (idx < 0 \|\| idx >= MAX_CODADEVS) {
6d6bd94f	143	pr_warn("%s: Bad minor number\n", __func__);
1da177e4 LT	144	return -1;
	145	}
	146
	147	return idx;
78f7d75e	148	Ebadf:
6d6bd94f	149	pr_warn("%s: Bad file\n", __func__);
78f7d75e	150	return -1;
1da177e4 LT	151	}
	152
	153	static int coda_fill_super(struct super_block sb, void data, int silent)
	154	{
a1b0aa87	155	struct inode *root = NULL;
da47c19e	156	struct venus_comm *vc;
1da177e4	157	struct CodaFid fid;
a1b0aa87	158	int error;
1da177e4 LT	159	int idx;
1da177e4 LT	160
9fd973e0 EB	161	if (task_active_pid_ns(current) != &init_pid_ns)
	162	return -EINVAL;
	163
1da177e4 LT	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
6d6bd94f	170	pr_info("%s: device index: %i\n", __func__, idx);
1da177e4 LT	171
1da177e4 LT	172	vc = &coda_comms[idx];
da47c19e	173	mutex_lock(&vc->vc_mutex);
f7cc02b8	174
1da177e4	175	if (!vc->vc_inuse) {
6d6bd94f	176	pr_warn("%s: No pseudo device\n", __func__);
f7cc02b8 YA	177	error = -EINVAL;
f7cc02b8 YA	178	goto unlock_out;
1da177e4 LT	179	}
1da177e4 LT	180
f7cc02b8	181	if (vc->vc_sb) {
6d6bd94f	182	pr_warn("%s: Device already mounted\n", __func__);
f7cc02b8 YA	183	error = -EBUSY;
f7cc02b8 YA	184	goto unlock_out;
1da177e4 LT	185	}
1da177e4 LT	186
1da177e4	187	vc->vc_sb = sb;
da47c19e	188	mutex_unlock(&vc->vc_mutex);
1da177e4	189
a1b0aa87	190	sb->s_fs_info = vc;
1751e8a6	191	sb->s_flags \|= SB_NOATIME;
fac1f0e3 JH	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;
9501e4c4	196	sb->s_d_op = &coda_dentry_operations;
a5695a79 JK	197
	198	error = super_setup_bdi(sb);
	199	if (error)
	200	goto error;
1da177e4 LT	201
	202	/* get root fid from Venus: this needs the root inode */
	203	error = venus_rootfid(sb, &fid);
	204	if ( error ) {
6d6bd94f FF	205	pr_warn("%s: coda_get_rootfid failed with %d\n",
6d6bd94f FF	206	__func__, error);
1da177e4 LT	207	goto error;
1da177e4 LT	208	}
6d6bd94f	209	pr_info("%s: rootfid is %s\n", __func__, coda_f2s(&fid));
1da177e4 LT	210
1da177e4 LT	211	/* make root inode */
f4947fbc AV	212	root = coda_cnode_make(&fid, sb);
	213	if (IS_ERR(root)) {
	214	error = PTR_ERR(root);
d9b4b319 FF	215	pr_warn("Failure of coda_cnode_make for root: error %d\n",
d9b4b319 FF	216	error);
f4947fbc	217	goto error;
1da177e4 LT	218	}
1da177e4 LT	219
6d6bd94f FF	220	pr_info("%s: rootinode is %ld dev %s\n",
6d6bd94f FF	221	__func__, root->i_ino, root->i_sb->s_id);
48fde701	222	sb->s_root = d_make_root(root);
f7cc02b8 YA	223	if (!sb->s_root) {
f7cc02b8 YA	224	error = -EINVAL;
1da177e4	225	goto error;
f7cc02b8	226	}
db719222	227	return 0;
1da177e4	228
f7cc02b8	229	error:
da47c19e	230	mutex_lock(&vc->vc_mutex);
f7cc02b8 YA	231	vc->vc_sb = NULL;
	232	sb->s_fs_info = NULL;
	233	unlock_out:
da47c19e	234	mutex_unlock(&vc->vc_mutex);
f7cc02b8	235	return error;
1da177e4 LT	236	}
	237
	238	static void coda_put_super(struct super_block *sb)
	239	{
da47c19e YA	240	struct venus_comm *vcp = coda_vcp(sb);
da47c19e YA	241	mutex_lock(&vcp->vc_mutex);
da47c19e	242	vcp->vc_sb = NULL;
a1b0aa87	243	sb->s_fs_info = NULL;
da47c19e	244	mutex_unlock(&vcp->vc_mutex);
1da177e4	245
f38cfb25	246	pr_info("Bye bye.\n");
1da177e4 LT	247	}
1da177e4 LT	248
b57922d9	249	static void coda_evict_inode(struct inode *inode)
1da177e4	250	{
91b0abe3	251	truncate_inode_pages_final(&inode->i_data);
dbd5768f	252	clear_inode(inode);
1da177e4 LT	253	coda_cache_clear_inode(inode);
	254	}
	255
a528d35e DH	256	int coda_getattr(const struct path path, struct kstat stat,
a528d35e DH	257	u32 request_mask, unsigned int flags)
1da177e4	258	{
a528d35e	259	int err = coda_revalidate_inode(d_inode(path->dentry));
1da177e4	260	if (!err)
a528d35e	261	generic_fillattr(d_inode(path->dentry), stat);
1da177e4 LT	262	return err;
	263	}
	264
	265	int coda_setattr(struct dentry de, struct iattr iattr)
	266	{
2b0143b5	267	struct inode *inode = d_inode(de);
1da177e4 LT	268	struct coda_vattr vattr;
	269	int error;
	270
1da177e4 LT	271	memset(&vattr, 0, sizeof(vattr));
1da177e4 LT	272
02027d42	273	inode->i_ctime = current_time(inode);
1da177e4 LT	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
f7cc02b8	280	if (!error) {
1da177e4 LT	281	coda_vattr_to_iattr(inode, &vattr);
	282	coda_cache_clear_inode(inode);
	283	}
1da177e4 LT	284	return error;
	285	}
	286
754661f1	287	const struct inode_operations coda_file_inode_operations = {
1da177e4 LT	288	.permission = coda_permission,
	289	.getattr = coda_getattr,
	290	.setattr = coda_setattr,
	291	};
	292
726c3342	293	static int coda_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4 LT	294	{
	295	int error;
	296
726c3342	297	error = venus_statfs(dentry, buf);
1da177e4	298
1da177e4 LT	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;
fac1f0e3	310	buf->f_bsize = 4096;
1da177e4 LT	311	buf->f_namelen = CODA_MAXNAMLEN;
	312
	313	return 0;
	314	}
	315
	316	/* init_coda: used by filesystems.c to register coda */
	317
3c26ff6e AV	318	static struct dentry coda_mount(struct file_system_type fs_type,
3c26ff6e AV	319	int flags, const char dev_name, void data)
1da177e4	320	{
3c26ff6e	321	return mount_nodev(fs_type, flags, data, coda_fill_super);
1da177e4 LT	322	}
	323
	324	struct file_system_type coda_fs_type = {
	325	.owner = THIS_MODULE,
	326	.name = "coda",
3c26ff6e	327	.mount = coda_mount,
1da177e4 LT	328	.kill_sb = kill_anon_super,
	329	.fs_flags = FS_BINARY_MOUNTDATA,
	330	};
7f78e035	331	MODULE_ALIAS_FS("coda");
1da177e4	332