- 根目录:
- fs
- jfs
- inode.c
/*
* Copyright (C) International Business Machines Corp., 2000-2004
* Portions Copyright (C) Christoph Hellwig, 2001-2002
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/mpage.h>
#include <linux/buffer_head.h>
#include <linux/pagemap.h>
#include <linux/quotaops.h>
#include <linux/writeback.h>
#include "jfs_incore.h"
#include "jfs_inode.h"
#include "jfs_filsys.h"
#include "jfs_imap.h"
#include "jfs_extent.h"
#include "jfs_unicode.h"
#include "jfs_debug.h"
struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
{
struct inode *inode;
int ret;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
ret = diRead(inode);
if (ret < 0) {
iget_failed(inode);
return ERR_PTR(ret);
}
if (S_ISREG(inode->i_mode)) {
inode->i_op = &jfs_file_inode_operations;
inode->i_fop = &jfs_file_operations;
inode->i_mapping->a_ops = &jfs_aops;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = &jfs_dir_inode_operations;
inode->i_fop = &jfs_dir_operations;
} else if (S_ISLNK(inode->i_mode)) {
if (inode->i_size >= IDATASIZE) {
inode->i_op = &page_symlink_inode_operations;
inode->i_mapping->a_ops = &jfs_aops;
} else {
inode->i_op = &jfs_fast_symlink_inode_operations;
/*
* The inline data should be null-terminated, but
* don't let on-disk corruption crash the kernel
*/
JFS_IP(inode)->i_inline[inode->i_size] = '\0';
}
} else {
inode->i_op = &jfs_file_inode_operations;
init_special_inode(inode, inode->i_mode, inode->i_rdev);
}
unlock_new_inode(inode);
return inode;
}
/*
* Workhorse of both fsync & write_inode
*/
int jfs_commit_inode(struct inode *inode, int wait)
{
int rc = 0;
tid_t tid;
static int noisy = 5;
jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
/*
* Don't commit if inode has been committed since last being
* marked dirty, or if it has been deleted.
*/
if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))
return 0;
if (isReadOnly(inode)) {
/* kernel allows writes to devices on read-only
* partitions and may think inode is dirty
*/
if (!special_file(inode->i_mode) && noisy) {
jfs_err("jfs_commit_inode(0x%p) called on "
"read-only volume", inode);
jfs_err("Is remount racy?");
noisy--;
}
return 0;
}
tid = txBegin(inode->i_sb, COMMIT_INODE);
mutex_lock(&JFS_IP(inode)->commit_mutex);
/*
* Retest inode state after taking commit_mutex
*/
if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
txEnd(tid);
mutex_unlock(&JFS_IP(inode)->commit_mutex);
return rc;
}
int jfs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
int wait = wbc->sync_mode == WB_SYNC_ALL;
if (test_cflag(COMMIT_Nolink, inode))
return 0;
/*
* If COMMIT_DIRTY is not set, the inode isn't really dirty.
* It has been committed since the last change, but was still
* on the dirty inode list.
*/
if (!test_cflag(COMMIT_Dirty, inode)) {
/* Make sure committed changes hit the disk */
jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
return 0;
}
if (jfs_commit_inode(inode, wait)) {
jfs_err("jfs_write_inode: jfs_commit_inode failed!");
return -EIO;
} else
return 0;
}
void jfs_evict_inode(struct inode *inode)
{
jfs_info("In jfs_evict_inode, inode = 0x%p", inode);
if (!inode->i_nlink && !is_bad_inode(inode)) {
dquot_initialize(inode);
if (JFS_IP(inode)->fileset == FILESYSTEM_I) {
truncate_inode_pages(&inode->i_data, 0);
if (test_cflag(COMMIT_Freewmap, inode))
jfs_free_zero_link(inode);
diFree(inode);
/*
* Free the inode from the quota allocation.
*/
dquot_initialize(inode);
dquot_free_inode(inode);
}
} else {
truncate_inode_pages(&inode->i_data, 0);
}
end_writeback(inode);
dquot_drop(inode);
}
void jfs_dirty_inode(struct inode *inode, int flags)
{
static int noisy = 5;
if (isReadOnly(inode)) {
if (!special_file(inode->i_mode) && noisy) {
/* kernel allows writes to devices on read-only
* partitions and may try to mark inode dirty
*/
jfs_err("jfs_dirty_inode called on read-only volume");
jfs_err("Is remount racy?");
noisy--;
}
return;
}
set_cflag(COMMIT_Dirty, inode);
}
int jfs_get_block(struct inode *ip, sector_t lblock,
struct buffer_head *bh_result, int create)
{
s64 lblock64 = lblock;
int rc = 0;
xad_t xad;
s64 xaddr;
int xflag;
s32 xlen = bh_result->b_size >> ip->i_blkbits;
/*
* Take appropriate lock on inode
*/
if (create)
IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
else
IREAD_LOCK(ip, RDWRLOCK_NORMAL);
if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
(!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&
xaddr) {
if (xflag & XAD_NOTRECORDED) {
if (!create)
/*
* Allocated but not recorded, read treats
* this as a hole
*/
goto unlock;
#ifdef _JFS_4K
XADoffset(&xad, lblock64);
XADlength(&xad, xlen);
XADaddress(&xad, xaddr);
#else /* _JFS_4K */
/*
* As long as block size = 4K, this isn't a problem.
* We should mark the whole page not ABNR, but how
* will we know to mark the other blocks BH_New?
*/
BUG();
#endif /* _JFS_4K */
rc = extRecord(ip, &xad);
if (rc)
goto unlock;
set_buffer_new(bh_result);
}
map_bh(bh_result, ip->i_sb, xaddr);
bh_result->b_size = xlen << ip->i_blkbits;
goto unlock;
}
if (!create)
goto unlock;
/*
* Allocate a new block
*/
#ifdef _JFS_4K
if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
goto unlock;
rc = extAlloc(ip, xlen, lblock64, &xad, false);
if (rc)
goto unlock;
set_buffer_new(bh_result);
map_bh(bh_result, ip->i_sb, addressXAD(&xad));
bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
#else /* _JFS_4K */
/*
* We need to do whatever it takes to keep all but the last buffers
* in 4K pages - see jfs_write.c
*/
BUG();
#endif /* _JFS_4K */
unlock:
/*
* Release lock on inode
*/
if (create)
IWRITE_UNLOCK(ip);
else
IREAD_UNLOCK(ip);
return rc;
}
static int jfs_writepage(struct page *page, struct writeback_control *wbc)
{
return block_write_full_page(page, jfs_get_block, wbc);
}
static int jfs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
return mpage_writepages(mapping, wbc, jfs_get_block);
}
static int jfs_readpage(struct file *file, struct page *page)
{
return mpage_readpage(page, jfs_get_block);
}
static int jfs_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
}
static int jfs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
int ret;
ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata,
jfs_get_block);
if (unlikely(ret)) {
loff_t isize = mapping->host->i_size;
if (pos + len > isize)
vmtruncate(mapping->host, isize);
}
return ret;
}
static sector_t jfs_bmap(struct address_space *mapping, sector_t block)
{
return generic_block_bmap(mapping, block, jfs_get_block);
}
static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
const struct iovec *iov, loff_t offset, unsigned long nr_segs)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
ssize_t ret;
ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
offset, nr_segs, jfs_get_block, NULL);
/*
* In case of error extending write may have instantiated a few
* blocks outside i_size. Trim these off again.
*/
if (unlikely((rw & WRITE) && ret < 0)) {
loff_t isize = i_size_read(inode);
loff_t end = offset + iov_length(iov, nr_segs);
if (end > isize)
vmtruncate(inode, isize);
}
return ret;
}
const struct address_space_operations jfs_aops = {
.readpage = jfs_readpage,
.readpages = jfs_readpages,
.writepage = jfs_writepage,
.writepages = jfs_writepages,
.write_begin = jfs_write_begin,
.write_end = nobh_write_end,
.bmap = jfs_bmap,
.direct_IO = jfs_direct_IO,
};
/*
* Guts of jfs_truncate. Called with locks already held. Can be called
* with directory for truncating directory index table.
*/
void jfs_truncate_nolock(struct inode *ip, loff_t length)
{
loff_t newsize;
tid_t tid;
ASSERT(length >= 0);
if (test_cflag(COMMIT_Nolink, ip)) {
xtTruncate(0, ip, length, COMMIT_WMAP);
return;
}
do {
tid = txBegin(ip->i_sb, 0);
/*
* The commit_mutex cannot be taken before txBegin.
* txBegin may block and there is a chance the inode
* could be marked dirty and need to be committed
* before txBegin unblocks
*/
mutex_lock(&JFS_IP(ip)->commit_mutex);
newsize = xtTruncate(tid, ip, length,
COMMIT_TRUNCATE | COMMIT_PWMAP);
if (newsize < 0) {
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
break;
}
ip->i_mtime = ip->i_ctime = CURRENT_TIME;
mark_inode_dirty(ip);
txCommit(tid, 1, &ip, 0);
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
} while (newsize > length); /* Truncate isn't always atomic */
}
void jfs_truncate(struct inode *ip)
{
jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
jfs_truncate_nolock(ip, ip->i_size);
IWRITE_UNLOCK(ip);
}