linux/fs/freevxfs/vxfs_inode.c
Christoph Hellwig 85fe4025c6 fs: do not assign default i_ino in new_inode
Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves.  For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:26:11 -04:00

355 lines
8.8 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"
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 (bp && 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 an error code.
*/
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 ERR_CAST(pp);
fail:
printk(KERN_WARNING "vxfs: unable to read inode %ld\n", (unsigned long)ino);
vxfs_put_page(pp);
return ERR_PTR(-ENOMEM);
}
/**
* 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)
{
struct vxfs_inode_info *vip;
vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_stilist);
return IS_ERR(vip) ? NULL : vip;
}
/**
* 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))) {
ip->i_ino = get_next_ino();
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_iget - get an inode
* @sbp: the superblock to get the inode for
* @ino: the number of the inode to get
*
* Description:
* vxfs_read_inode creates an inode, reads the disk inode for @ino and fills
* in all relevant fields in the new inode.
*/
struct inode *
vxfs_iget(struct super_block *sbp, ino_t ino)
{
struct vxfs_inode_info *vip;
const struct address_space_operations *aops;
struct inode *ip;
ip = iget_locked(sbp, ino);
if (!ip)
return ERR_PTR(-ENOMEM);
if (!(ip->i_state & I_NEW))
return ip;
vip = __vxfs_iget(ino, VXFS_SBI(sbp)->vsi_ilist);
if (IS_ERR(vip)) {
iget_failed(ip);
return ERR_CAST(vip);
}
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;
vip->vii_immed.vi_immed[ip->i_size] = '\0';
}
} else
init_special_inode(ip, ip->i_mode, old_decode_dev(vip->vii_rdev));
unlock_new_inode(ip);
return ip;
}
/**
* vxfs_evict_inode - remove inode from main memory
* @ip: inode to discard.
*
* Description:
* vxfs_evict_inode() is called on the final iput and frees the private
* inode area.
*/
void
vxfs_evict_inode(struct inode *ip)
{
truncate_inode_pages(&ip->i_data, 0);
end_writeback(ip);
kmem_cache_free(vxfs_inode_cachep, ip->i_private);
}