[mirror_ubuntu-jammy-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 "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_free_inode(struct inode *inode)
{
	kmem_cache_free(coda_inode_cachep, ITOC(inode));
}

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,
	.free_inode	= coda_free_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);
	mutex_destroy(&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>
8fc8b9df	30	#include "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
d984892b	57	static void coda_free_inode(struct inode *inode)
1da177e4 LT	58	{
	59	kmem_cache_free(coda_inode_cachep, ITOC(inode));
	60	}
	61
51cc5068	62	static void init_once(void *foo)
1da177e4 LT	63	{
	64	struct coda_inode_info ei = (struct coda_inode_info ) foo;
	65
a35afb83	66	inode_init_once(&ei->vfs_inode);
1da177e4	67	}
20c2df83	68
5f356fd4	69	int __init coda_init_inodecache(void)
1da177e4 LT	70	{
1da177e4 LT	71	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
5d097056 VD	72	sizeof(struct coda_inode_info), 0,
	73	SLAB_RECLAIM_ACCOUNT\|SLAB_MEM_SPREAD\|
	74	SLAB_ACCOUNT, init_once);
1da177e4 LT	75	if (coda_inode_cachep == NULL)
	76	return -ENOMEM;
	77	return 0;
	78	}
	79
	80	void coda_destroy_inodecache(void)
	81	{
8c0a8537 KS	82	/*
	83	* Make sure all delayed rcu free inodes are flushed before we
	84	* destroy cache.
	85	*/
	86	rcu_barrier();
1a1d92c1	87	kmem_cache_destroy(coda_inode_cachep);
1da177e4 LT	88	}
	89
	90	static int coda_remount(struct super_block sb, int flags, char *data)
	91	{
02b9984d	92	sync_filesystem(sb);
1751e8a6	93	*flags \|= SB_NOATIME;
1da177e4 LT	94	return 0;
	95	}
	96
	97	/* exported operations */
ee9b6d61	98	static const struct super_operations coda_super_operations =
1da177e4 LT	99	{
1da177e4 LT	100	.alloc_inode = coda_alloc_inode,
d984892b	101	.free_inode = coda_free_inode,
b57922d9	102	.evict_inode = coda_evict_inode,
1da177e4 LT	103	.put_super = coda_put_super,
	104	.statfs = coda_statfs,
	105	.remount_fs = coda_remount,
	106	};
	107
	108	static int get_device_index(struct coda_mount_data *data)
	109	{
2903ff01	110	struct fd f;
1da177e4	111	struct inode *inode;
2903ff01	112	int idx;
1da177e4	113
78f7d75e	114	if (data == NULL) {
6d6bd94f	115	pr_warn("%s: Bad mount data\n", __func__);
1da177e4 LT	116	return -1;
	117	}
	118
78f7d75e	119	if (data->version != CODA_MOUNT_VERSION) {
6d6bd94f	120	pr_warn("%s: Bad mount version\n", __func__);
1da177e4 LT	121	return -1;
	122	}
	123
2903ff01 AV	124	f = fdget(data->fd);
2903ff01 AV	125	if (!f.file)
78f7d75e	126	goto Ebadf;
496ad9aa	127	inode = file_inode(f.file);
78f7d75e	128	if (!S_ISCHR(inode->i_mode) \|\| imajor(inode) != CODA_PSDEV_MAJOR) {
2903ff01	129	fdput(f);
78f7d75e	130	goto Ebadf;
1da177e4 LT	131	}
	132
	133	idx = iminor(inode);
2903ff01	134	fdput(f);
1da177e4	135
78f7d75e	136	if (idx < 0 \|\| idx >= MAX_CODADEVS) {
6d6bd94f	137	pr_warn("%s: Bad minor number\n", __func__);
1da177e4 LT	138	return -1;
	139	}
	140
	141	return idx;
78f7d75e	142	Ebadf:
6d6bd94f	143	pr_warn("%s: Bad file\n", __func__);
78f7d75e	144	return -1;
1da177e4 LT	145	}
	146
	147	static int coda_fill_super(struct super_block sb, void data, int silent)
	148	{
a1b0aa87	149	struct inode *root = NULL;
da47c19e	150	struct venus_comm *vc;
1da177e4	151	struct CodaFid fid;
a1b0aa87	152	int error;
1da177e4 LT	153	int idx;
1da177e4 LT	154
9fd973e0 EB	155	if (task_active_pid_ns(current) != &init_pid_ns)
	156	return -EINVAL;
	157
1da177e4 LT	158	idx = get_device_index((struct coda_mount_data *) data);
	159
	160	/* Ignore errors in data, for backward compatibility */
	161	if(idx == -1)
	162	idx = 0;
	163
6d6bd94f	164	pr_info("%s: device index: %i\n", __func__, idx);
1da177e4 LT	165
1da177e4 LT	166	vc = &coda_comms[idx];
da47c19e	167	mutex_lock(&vc->vc_mutex);
f7cc02b8	168
1da177e4	169	if (!vc->vc_inuse) {
6d6bd94f	170	pr_warn("%s: No pseudo device\n", __func__);
f7cc02b8 YA	171	error = -EINVAL;
f7cc02b8 YA	172	goto unlock_out;
1da177e4 LT	173	}
1da177e4 LT	174
f7cc02b8	175	if (vc->vc_sb) {
6d6bd94f	176	pr_warn("%s: Device already mounted\n", __func__);
f7cc02b8 YA	177	error = -EBUSY;
f7cc02b8 YA	178	goto unlock_out;
1da177e4 LT	179	}
1da177e4 LT	180
1da177e4	181	vc->vc_sb = sb;
da47c19e	182	mutex_unlock(&vc->vc_mutex);
1da177e4	183
a1b0aa87	184	sb->s_fs_info = vc;
1751e8a6	185	sb->s_flags \|= SB_NOATIME;
fac1f0e3 JH	186	sb->s_blocksize = 4096; /* XXXXX what do we put here?? */
	187	sb->s_blocksize_bits = 12;
	188	sb->s_magic = CODA_SUPER_MAGIC;
	189	sb->s_op = &coda_super_operations;
9501e4c4	190	sb->s_d_op = &coda_dentry_operations;
a5695a79 JK	191
	192	error = super_setup_bdi(sb);
	193	if (error)
	194	goto error;
1da177e4 LT	195
	196	/* get root fid from Venus: this needs the root inode */
	197	error = venus_rootfid(sb, &fid);
	198	if ( error ) {
6d6bd94f FF	199	pr_warn("%s: coda_get_rootfid failed with %d\n",
6d6bd94f FF	200	__func__, error);
1da177e4 LT	201	goto error;
1da177e4 LT	202	}
6d6bd94f	203	pr_info("%s: rootfid is %s\n", __func__, coda_f2s(&fid));
1da177e4 LT	204
1da177e4 LT	205	/* make root inode */
f4947fbc AV	206	root = coda_cnode_make(&fid, sb);
	207	if (IS_ERR(root)) {
	208	error = PTR_ERR(root);
d9b4b319 FF	209	pr_warn("Failure of coda_cnode_make for root: error %d\n",
d9b4b319 FF	210	error);
f4947fbc	211	goto error;
1da177e4 LT	212	}
1da177e4 LT	213
6d6bd94f FF	214	pr_info("%s: rootinode is %ld dev %s\n",
6d6bd94f FF	215	__func__, root->i_ino, root->i_sb->s_id);
48fde701	216	sb->s_root = d_make_root(root);
f7cc02b8 YA	217	if (!sb->s_root) {
f7cc02b8 YA	218	error = -EINVAL;
1da177e4	219	goto error;
f7cc02b8	220	}
db719222	221	return 0;
1da177e4	222
f7cc02b8	223	error:
da47c19e	224	mutex_lock(&vc->vc_mutex);
f7cc02b8 YA	225	vc->vc_sb = NULL;
	226	sb->s_fs_info = NULL;
	227	unlock_out:
da47c19e	228	mutex_unlock(&vc->vc_mutex);
f7cc02b8	229	return error;
1da177e4 LT	230	}
	231
	232	static void coda_put_super(struct super_block *sb)
	233	{
da47c19e YA	234	struct venus_comm *vcp = coda_vcp(sb);
da47c19e YA	235	mutex_lock(&vcp->vc_mutex);
da47c19e	236	vcp->vc_sb = NULL;
a1b0aa87	237	sb->s_fs_info = NULL;
da47c19e	238	mutex_unlock(&vcp->vc_mutex);
79a0d65e	239	mutex_destroy(&vcp->vc_mutex);
1da177e4	240
f38cfb25	241	pr_info("Bye bye.\n");
1da177e4 LT	242	}
1da177e4 LT	243
b57922d9	244	static void coda_evict_inode(struct inode *inode)
1da177e4	245	{
91b0abe3	246	truncate_inode_pages_final(&inode->i_data);
dbd5768f	247	clear_inode(inode);
1da177e4 LT	248	coda_cache_clear_inode(inode);
	249	}
	250
a528d35e DH	251	int coda_getattr(const struct path path, struct kstat stat,
a528d35e DH	252	u32 request_mask, unsigned int flags)
1da177e4	253	{
a528d35e	254	int err = coda_revalidate_inode(d_inode(path->dentry));
1da177e4	255	if (!err)
a528d35e	256	generic_fillattr(d_inode(path->dentry), stat);
1da177e4 LT	257	return err;
	258	}
	259
	260	int coda_setattr(struct dentry de, struct iattr iattr)
	261	{
2b0143b5	262	struct inode *inode = d_inode(de);
1da177e4 LT	263	struct coda_vattr vattr;
	264	int error;
	265
1da177e4 LT	266	memset(&vattr, 0, sizeof(vattr));
1da177e4 LT	267
02027d42	268	inode->i_ctime = current_time(inode);
1da177e4 LT	269	coda_iattr_to_vattr(iattr, &vattr);
	270	vattr.va_type = C_VNON; /* cannot set type */
	271
	272	/* Venus is responsible for truncating the container-file!!! */
	273	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
	274
f7cc02b8	275	if (!error) {
1da177e4 LT	276	coda_vattr_to_iattr(inode, &vattr);
	277	coda_cache_clear_inode(inode);
	278	}
1da177e4 LT	279	return error;
	280	}
	281
754661f1	282	const struct inode_operations coda_file_inode_operations = {
1da177e4 LT	283	.permission = coda_permission,
	284	.getattr = coda_getattr,
	285	.setattr = coda_setattr,
	286	};
	287
726c3342	288	static int coda_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4 LT	289	{
	290	int error;
	291
726c3342	292	error = venus_statfs(dentry, buf);
1da177e4	293
1da177e4 LT	294	if (error) {
	295	/* fake something like AFS does */
	296	buf->f_blocks = 9000000;
	297	buf->f_bfree = 9000000;
	298	buf->f_bavail = 9000000;
	299	buf->f_files = 9000000;
	300	buf->f_ffree = 9000000;
	301	}
	302
	303	/* and fill in the rest */
	304	buf->f_type = CODA_SUPER_MAGIC;
fac1f0e3	305	buf->f_bsize = 4096;
1da177e4 LT	306	buf->f_namelen = CODA_MAXNAMLEN;
	307
	308	return 0;
	309	}
	310
	311	/* init_coda: used by filesystems.c to register coda */
	312
3c26ff6e AV	313	static struct dentry coda_mount(struct file_system_type fs_type,
3c26ff6e AV	314	int flags, const char dev_name, void data)
1da177e4	315	{
3c26ff6e	316	return mount_nodev(fs_type, flags, data, coda_fill_super);
1da177e4 LT	317	}
	318
	319	struct file_system_type coda_fs_type = {
	320	.owner = THIS_MODULE,
	321	.name = "coda",
3c26ff6e	322	.mount = coda_mount,
1da177e4 LT	323	.kill_sb = kill_anon_super,
	324	.fs_flags = FS_BINARY_MOUNTDATA,
	325	};
7f78e035	326	MODULE_ALIAS_FS("coda");
1da177e4	327