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linux/fs/freevxfs/vxfs_inode.c
Arjan van de Ven 754661f143 [PATCH] mark struct inode_operations const 1
Many struct inode_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00

342 lines
8.6 KiB
C

/*
* Copyright (c) 2000-2001 Christoph Hellwig.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL").
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Veritas filesystem driver - inode routines.
*/
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/pagemap.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include "vxfs.h"
#include "vxfs_inode.h"
#include "vxfs_extern.h"
extern const struct address_space_operations vxfs_aops;
extern const struct address_space_operations vxfs_immed_aops;
extern const struct inode_operations vxfs_immed_symlink_iops;
struct kmem_cache *vxfs_inode_cachep;
#ifdef DIAGNOSTIC
/*
* Dump inode contents (partially).
*/
void
vxfs_dumpi(struct vxfs_inode_info *vip, ino_t ino)
{
printk(KERN_DEBUG "\n\n");
if (ino)
printk(KERN_DEBUG "dumping vxfs inode %ld\n", ino);
else
printk(KERN_DEBUG "dumping unknown vxfs inode\n");
printk(KERN_DEBUG "---------------------------\n");
printk(KERN_DEBUG "mode is %x\n", vip->vii_mode);
printk(KERN_DEBUG "nlink:%u, uid:%u, gid:%u\n",
vip->vii_nlink, vip->vii_uid, vip->vii_gid);
printk(KERN_DEBUG "size:%Lx, blocks:%u\n",
vip->vii_size, vip->vii_blocks);
printk(KERN_DEBUG "orgtype:%u\n", vip->vii_orgtype);
}
#endif
/**
* vxfs_blkiget - find inode based on extent #
* @sbp: superblock of the filesystem we search in
* @extent: number of the extent to search
* @ino: inode number to search
*
* Description:
* vxfs_blkiget searches inode @ino in the filesystem described by
* @sbp in the extent @extent.
* Returns the matching VxFS inode on success, else a NULL pointer.
*
* NOTE:
* While __vxfs_iget uses the pagecache vxfs_blkiget uses the
* buffercache. This function should not be used outside the
* read_super() method, otherwise the data may be incoherent.
*/
struct vxfs_inode_info *
vxfs_blkiget(struct super_block *sbp, u_long extent, ino_t ino)
{
struct buffer_head *bp;
u_long block, offset;
block = extent + ((ino * VXFS_ISIZE) / sbp->s_blocksize);
offset = ((ino % (sbp->s_blocksize / VXFS_ISIZE)) * VXFS_ISIZE);
bp = sb_bread(sbp, block);
if (buffer_mapped(bp)) {
struct vxfs_inode_info *vip;
struct vxfs_dinode *dip;
if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
goto fail;
dip = (struct vxfs_dinode *)(bp->b_data + offset);
memcpy(vip, dip, sizeof(*vip));
#ifdef DIAGNOSTIC
vxfs_dumpi(vip, ino);
#endif
brelse(bp);
return (vip);
}
fail:
printk(KERN_WARNING "vxfs: unable to read block %ld\n", block);
brelse(bp);
return NULL;
}
/**
* __vxfs_iget - generic find inode facility
* @sbp: VFS superblock
* @ino: inode number
* @ilistp: inode list
*
* Description:
* Search the for inode number @ino in the filesystem
* described by @sbp. Use the specified inode table (@ilistp).
* Returns the matching VxFS inode on success, else a NULL pointer.
*/
static struct vxfs_inode_info *
__vxfs_iget(ino_t ino, struct inode *ilistp)
{
struct page *pp;
u_long offset;
offset = (ino % (PAGE_SIZE / VXFS_ISIZE)) * VXFS_ISIZE;
pp = vxfs_get_page(ilistp->i_mapping, ino * VXFS_ISIZE / PAGE_SIZE);
if (!IS_ERR(pp)) {
struct vxfs_inode_info *vip;
struct vxfs_dinode *dip;
caddr_t kaddr = (char *)page_address(pp);
if (!(vip = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL)))
goto fail;
dip = (struct vxfs_dinode *)(kaddr + offset);
memcpy(vip, dip, sizeof(*vip));
#ifdef DIAGNOSTIC
vxfs_dumpi(vip, ino);
#endif
vxfs_put_page(pp);
return (vip);
}
printk(KERN_WARNING "vxfs: error on page %p\n", pp);
return NULL;
fail:
printk(KERN_WARNING "vxfs: unable to read inode %ld\n", (unsigned long)ino);
vxfs_put_page(pp);
return NULL;
}
/**
* vxfs_stiget - find inode using the structural inode list
* @sbp: VFS superblock
* @ino: inode #
*
* Description:
* Find inode @ino in the filesystem described by @sbp using
* the structural inode list.
* Returns the matching VxFS inode on success, else a NULL pointer.
*/
struct vxfs_inode_info *
vxfs_stiget(struct super_block *sbp, ino_t ino)
{
return __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_stilist);
}
/**
* vxfs_transmod - mode for a VxFS inode
* @vip: VxFS inode
*
* Description:
* vxfs_transmod returns a Linux mode_t for a given
* VxFS inode structure.
*/
static __inline__ mode_t
vxfs_transmod(struct vxfs_inode_info *vip)
{
mode_t ret = vip->vii_mode & ~VXFS_TYPE_MASK;
if (VXFS_ISFIFO(vip))
ret |= S_IFIFO;
if (VXFS_ISCHR(vip))
ret |= S_IFCHR;
if (VXFS_ISDIR(vip))
ret |= S_IFDIR;
if (VXFS_ISBLK(vip))
ret |= S_IFBLK;
if (VXFS_ISLNK(vip))
ret |= S_IFLNK;
if (VXFS_ISREG(vip))
ret |= S_IFREG;
if (VXFS_ISSOC(vip))
ret |= S_IFSOCK;
return (ret);
}
/**
* vxfs_iinit- helper to fill inode fields
* @ip: VFS inode
* @vip: VxFS inode
*
* Description:
* vxfs_instino is a helper function to fill in all relevant
* fields in @ip from @vip.
*/
static void
vxfs_iinit(struct inode *ip, struct vxfs_inode_info *vip)
{
ip->i_mode = vxfs_transmod(vip);
ip->i_uid = (uid_t)vip->vii_uid;
ip->i_gid = (gid_t)vip->vii_gid;
ip->i_nlink = vip->vii_nlink;
ip->i_size = vip->vii_size;
ip->i_atime.tv_sec = vip->vii_atime;
ip->i_ctime.tv_sec = vip->vii_ctime;
ip->i_mtime.tv_sec = vip->vii_mtime;
ip->i_atime.tv_nsec = 0;
ip->i_ctime.tv_nsec = 0;
ip->i_mtime.tv_nsec = 0;
ip->i_blocks = vip->vii_blocks;
ip->i_generation = vip->vii_gen;
ip->i_private = vip;
}
/**
* vxfs_get_fake_inode - get fake inode structure
* @sbp: filesystem superblock
* @vip: fspriv inode
*
* Description:
* vxfs_fake_inode gets a fake inode (not in the inode hash) for a
* superblock, vxfs_inode pair.
* Returns the filled VFS inode.
*/
struct inode *
vxfs_get_fake_inode(struct super_block *sbp, struct vxfs_inode_info *vip)
{
struct inode *ip = NULL;
if ((ip = new_inode(sbp))) {
vxfs_iinit(ip, vip);
ip->i_mapping->a_ops = &vxfs_aops;
}
return (ip);
}
/**
* vxfs_put_fake_inode - free faked inode
* *ip: VFS inode
*
* Description:
* vxfs_put_fake_inode frees all data asssociated with @ip.
*/
void
vxfs_put_fake_inode(struct inode *ip)
{
iput(ip);
}
/**
* vxfs_read_inode - fill in inode information
* @ip: inode pointer to fill
*
* Description:
* vxfs_read_inode reads the disk inode for @ip and fills
* in all relevant fields in @ip.
*/
void
vxfs_read_inode(struct inode *ip)
{
struct super_block *sbp = ip->i_sb;
struct vxfs_inode_info *vip;
const struct address_space_operations *aops;
ino_t ino = ip->i_ino;
if (!(vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_ilist)))
return;
vxfs_iinit(ip, vip);
if (VXFS_ISIMMED(vip))
aops = &vxfs_immed_aops;
else
aops = &vxfs_aops;
if (S_ISREG(ip->i_mode)) {
ip->i_fop = &generic_ro_fops;
ip->i_mapping->a_ops = aops;
} else if (S_ISDIR(ip->i_mode)) {
ip->i_op = &vxfs_dir_inode_ops;
ip->i_fop = &vxfs_dir_operations;
ip->i_mapping->a_ops = aops;
} else if (S_ISLNK(ip->i_mode)) {
if (!VXFS_ISIMMED(vip)) {
ip->i_op = &page_symlink_inode_operations;
ip->i_mapping->a_ops = &vxfs_aops;
} else
ip->i_op = &vxfs_immed_symlink_iops;
} else
init_special_inode(ip, ip->i_mode, old_decode_dev(vip->vii_rdev));
return;
}
/**
* vxfs_clear_inode - remove inode from main memory
* @ip: inode to discard.
*
* Description:
* vxfs_clear_inode() is called on the final iput and frees the private
* inode area.
*/
void
vxfs_clear_inode(struct inode *ip)
{
kmem_cache_free(vxfs_inode_cachep, ip->i_private);
}