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|
/*
* linux/fs/minix/inode.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* Copyright (C) 1996 Gertjan van Wingerde
* Minix V2 fs support.
*
* Modified for 680x0 by Andreas Schwab
* Updated to filesystem version 3 by Daniel Aragones
*/
#include <linux/module.h>
#include "minix.h"
#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/highuid.h>
#include <linux/vfs.h>
#include <linux/writeback.h>
static int minix_write_inode(struct inode *inode,
struct writeback_control *wbc);
static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
static int minix_remount (struct super_block * sb, int * flags, char * data);
static void minix_evict_inode(struct inode *inode)
{
truncate_inode_pages(&inode->i_data, 0);
if (!inode->i_nlink) {
inode->i_size = 0;
minix_truncate(inode);
}
invalidate_inode_buffers(inode);
end_writeback(inode);
if (!inode->i_nlink)
minix_free_inode(inode);
}
static void minix_put_super(struct super_block *sb)
{
int i;
struct minix_sb_info *sbi = minix_sb(sb);
if (!(sb->s_flags & MS_RDONLY)) {
if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
sbi->s_ms->s_state = sbi->s_mount_state;
mark_buffer_dirty(sbi->s_sbh);
}
for (i = 0; i < sbi->s_imap_blocks; i++)
brelse(sbi->s_imap[i]);
for (i = 0; i < sbi->s_zmap_blocks; i++)
brelse(sbi->s_zmap[i]);
brelse (sbi->s_sbh);
kfree(sbi->s_imap);
sb->s_fs_info = NULL;
kfree(sbi);
}
static struct kmem_cache * minix_inode_cachep;
static struct inode *minix_alloc_inode(struct super_block *sb)
{
struct minix_inode_info *ei;
ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
if (!ei)
return NULL;
return &ei->vfs_inode;
}
static void minix_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(minix_inode_cachep, minix_i(inode));
}
static void minix_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, minix_i_callback);
}
static void init_once(void *foo)
{
struct minix_inode_info *ei = (struct minix_inode_info *) foo;
inode_init_once(&ei->vfs_inode);
}
static int init_inodecache(void)
{
minix_inode_cachep = kmem_cache_create("minix_inode_cache",
sizeof(struct minix_inode_info),
0, (SLAB_RECLAIM_ACCOUNT|
SLAB_MEM_SPREAD),
init_once);
if (minix_inode_cachep == NULL)
return -ENOMEM;
return 0;
}
static void destroy_inodecache(void)
{
kmem_cache_destroy(minix_inode_cachep);
}
static const struct super_operations minix_sops = {
.alloc_inode = minix_alloc_inode,
.destroy_inode = minix_destroy_inode,
.write_inode = minix_write_inode,
.evict_inode = minix_evict_inode,
.put_super = minix_put_super,
.statfs = minix_statfs,
.remount_fs = minix_remount,
};
static int minix_remount (struct super_block * sb, int * flags, char * data)
{
struct minix_sb_info * sbi = minix_sb(sb);
struct minix_super_block * ms;
ms = sbi->s_ms;
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (*flags & MS_RDONLY) {
if (ms->s_state & MINIX_VALID_FS ||
!(sbi->s_mount_state & MINIX_VALID_FS))
return 0;
/* Mounting a rw partition read-only. */
if (sbi->s_version != MINIX_V3)
ms->s_state = sbi->s_mount_state;
mark_buffer_dirty(sbi->s_sbh);
} else {
/* Mount a partition which is read-only, read-write. */
if (sbi->s_version != MINIX_V3) {
sbi->s_mount_state = ms->s_state;
ms->s_state &= ~MINIX_VALID_FS;
} else {
sbi->s_mount_state = MINIX_VALID_FS;
}
mark_buffer_dirty(sbi->s_sbh);
if (!(sbi->s_mount_state & MINIX_VALID_FS))
printk("MINIX-fs warning: remounting unchecked fs, "
"running fsck is recommended\n");
else if ((sbi->s_mount_state & MINIX_ERROR_FS))
printk("MINIX-fs warning: remounting fs with errors, "
"running fsck is recommended\n");
}
return 0;
}
static int minix_fill_super(struct super_block *s, void *data, int silent)
{
struct buffer_head *bh;
struct buffer_head **map;
struct minix_super_block *ms;
struct minix3_super_block *m3s = NULL;
unsigned long i, block;
struct inode *root_inode;
struct minix_sb_info *sbi;
int ret = -EINVAL;
sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
s->s_fs_info = sbi;
BUILD_BUG_ON(32 != sizeof (struct minix_inode));
BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
if (!sb_set_blocksize(s, BLOCK_SIZE))
goto out_bad_hblock;
if (!(bh = sb_bread(s, 1)))
goto out_bad_sb;
ms = (struct minix_super_block *) bh->b_data;
sbi->s_ms = ms;
sbi->s_sbh = bh;
sbi->s_mount_state = ms->s_state;
sbi->s_ninodes = ms->s_ninodes;
sbi->s_nzones = ms->s_nzones;
sbi->s_imap_blocks = ms->s_imap_blocks
|