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/*
* Extended attribute handling for presto.
*
* Copyright (C) 2001. All rights reserved.
* Shirish H. Phatak
* Tacit Networks, Inc.
*
*/
#define __NO_VERSION__
#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/locks.h>
#include <linux/unistd.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/locks.h>
#include <linux/string.h>
#include <asm/uaccess.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <asm/segment.h>
#include <linux/smp_lock.h>
#include <linux/intermezzo_fs.h>
#include <linux/intermezzo_upcall.h>
#include <linux/intermezzo_psdev.h>
#include <linux/intermezzo_kml.h>
#ifdef CONFIG_FS_EXT_ATTR
#include <linux/ext_attr.h>
extern inline void presto_debug_fail_blkdev(struct presto_file_set *fset,
unsigned long value);
extern int presto_prep(struct dentry *, struct presto_cache **,
struct presto_file_set **);
/* VFS interface */
/* XXX! Fixme test for user defined attributes */
int presto_set_ext_attr(struct inode *inode,
const char *name, void *buffer,
size_t buffer_len, int flags)
{
int error;
struct presto_cache *cache;
struct presto_file_set *fset;
struct lento_vfs_context info;
struct dentry *dentry;
int minor = presto_i2m(inode);
char *buf = NULL;
ENTRY;
if (minor < 0) {
EXIT;
return -1;
}
if ( ISLENTO(minor) ) {
EXIT;
return -EINVAL;
}
/* BAD...vfs should really pass down the dentry to use, especially
* since every other operation in iops does. But for now
* we do a reverse mapping from inode to the first dentry
*/
if (list_empty(&inode->i_dentry)) {
printk("No alias for inode %d\n", (int) inode->i_ino);
EXIT;
return -EINVAL;
}
dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias);
error = presto_prep(dentry, &cache, &fset);
if ( error ) {
EXIT;
return error;
}
if ((buffer != NULL) && (buffer_len != 0)) {
/* If buffer is a user space pointer copy it to kernel space
* and reset the flag. We do this since the journal functions need
* access to the contents of the buffer, and the file system
* does not care. When we actually invoke the function, we remove
* the EXT_ATTR_FLAG_USER flag.
*
* XXX:Check if the "fs does not care" assertion is always true -SHP
* (works for ext3)
*/
if (flags & EXT_ATTR_FLAG_USER) {
PRESTO_ALLOC(buf, char *, buffer_len);
if (!buf) {
printk("InterMezzo: out of memory!!!\n");
return -ENOMEM;
}
error = copy_from_user(buf, buffer, buffer_len);
if (error)
return error;
} else
buf = buffer;
} else
buf = buffer;
if ( presto_get_permit(inode) < 0 ) {
EXIT;
if (buffer_len && (flags & EXT_ATTR_FLAG_USER))
PRESTO_FREE(buf, buffer_len);
return -EROFS;
}
/* Simulate presto_setup_info */
memset(&info, 0, sizeof(info));
/* For now redundant..but we keep it around just in case */
info.flags = LENTO_FL_IGNORE_TIME;
if (!ISLENTO(cache->cache_psdev->uc_minor))
info.flags |= LENTO_FL_KML;
/* We pass in the kernel space pointer and reset the
* EXT_ATTR_FLAG_USER flag.
* See comments above.
*/
/* Note that mode is already set by VFS so we send in a NULL */
error = presto_do_set_ext_attr(fset, dentry, name, buf,
buffer_len, flags & ~EXT_ATTR_FLAG_USER,
NULL, &info);
presto_put_permit(inode);
if (buffer_len && (flags & EXT_ATTR_FLAG_USER))
PRESTO_FREE(buf, buffer_len);
EXIT;
return error;
}
/* Lento Interface */
/* XXX: ignore flags? We should be forcing these operations through? -SHP*/
int lento_set_ext_attr(const char *path, const char *name,
void *buffer, size_t buffer_len, int flags, mode_t mode,
struct lento_vfs_context *info)
{
int error;
char * pathname;
struct nameidata nd;
struct dentry *dentry;
struct presto_file_set *fset;
ENTRY;
lock_kernel();
pathname=getname(path);
error = PTR_ERR(pathname);
if (IS_ERR(pathname)) {
EXIT;
goto exit;
}
/* Note that ext_attrs apply to both files and directories..*/
error=presto_walk(pathname,&nd);
if (error)
goto exit;
dentry = nd.dentry;
fset = presto_fset(dentry);
error = -EINVAL;
if ( !fset ) {
printk("No fileset!\n");
EXIT;
goto exit_dentry;
}
if (buffer==NULL) buffer_len=0;
error = presto_do_set_ext_attr(fset, dentry, name, buffer,
buffer_len, flags, &mode, info);
exit_dentry:
path_release(&nd);
exit_path:
putname(pathname);
exit:
unlock_kernel();
return error;
}
#endif /*CONFIG_FS_EXT_ATTR*/
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