[mirror_ubuntu-focal-kernel.git] / 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/uio.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"
#include "jfs_dmap.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_nohighmem(inode);
			inode->i_mapping->a_ops = &jfs_aops;
		} else {
			inode->i_op = &jfs_fast_symlink_inode_operations;
			inode->i_link = JFS_IP(inode)->i_inline;
			/*
			 * The inline data should be null-terminated, but
			 * don't let on-disk corruption crash the kernel
			 */
			inode->i_link[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 (inode->i_nlink == 0)
		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)
{
	struct jfs_inode_info *ji = JFS_IP(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_final(&inode->i_data);

			if (test_cflag(COMMIT_Freewmap, inode))
				jfs_free_zero_link(inode);

			diFree(inode);

			/*
			 * Free the inode from the quota allocation.
			 */
			dquot_free_inode(inode);
		}
	} else {
		truncate_inode_pages_final(&inode->i_data);
	}
	clear_inode(inode);
	dquot_drop(inode);

	BUG_ON(!list_empty(&ji->anon_inode_list));

	spin_lock_irq(&ji->ag_lock);
	if (ji->active_ag != -1) {
		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
		atomic_dec(&bmap->db_active[ji->active_ag]);
		ji->active_ag = -1;
	}
	spin_unlock_irq(&ji->ag_lock);
}

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 void jfs_write_failed(struct address_space *mapping, loff_t to)
{
	struct inode *inode = mapping->host;

	if (to > inode->i_size) {
		truncate_pagecache(inode, inode->i_size);
		jfs_truncate(inode);
	}
}

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))
		jfs_write_failed(mapping, pos + len);

	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(struct kiocb *iocb, struct iov_iter *iter)
{
	struct file *file = iocb->ki_filp;
	struct address_space *mapping = file->f_mapping;
	struct inode *inode = file->f_mapping->host;
	size_t count = iov_iter_count(iter);
	ssize_t ret;

	ret = blockdev_direct_IO(iocb, inode, iter, jfs_get_block);

	/*
	 * In case of error extending write may have instantiated a few
	 * blocks outside i_size. Trim these off again.
	 */
	if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) {
		loff_t isize = i_size_read(inode);
		loff_t end = iocb->ki_pos + count;

		if (end > isize)
			jfs_write_failed(mapping, end);
	}

	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(ip);
		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);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (C) International Business Machines Corp., 2000-2004
	3	* Portions Copyright (C) Christoph Hellwig, 2001-2002
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
63f83c9f	7	* the Free Software Foundation; either version 2 of the License, or
1da177e4	8	* (at your option) any later version.
63f83c9f	9	*
1da177e4 LT	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	13	* the GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
63f83c9f	16	* along with this program; if not, write to the Free Software
1da177e4 LT	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	18	*/
	19
	20	#include <linux/fs.h>
	21	#include <linux/mpage.h>
	22	#include <linux/buffer_head.h>
	23	#include <linux/pagemap.h>
	24	#include <linux/quotaops.h>
e2e40f2c	25	#include <linux/uio.h>
a9185b41	26	#include <linux/writeback.h>
1da177e4	27	#include "jfs_incore.h"
1868f4aa	28	#include "jfs_inode.h"
1da177e4 LT	29	#include "jfs_filsys.h"
	30	#include "jfs_imap.h"
	31	#include "jfs_extent.h"
	32	#include "jfs_unicode.h"
	33	#include "jfs_debug.h"
b3b4a6e3	34	#include "jfs_dmap.h"
1da177e4 LT	35
1da177e4 LT	36
eab1df71	37	struct inode jfs_iget(struct super_block sb, unsigned long ino)
1da177e4	38	{
eab1df71 DH	39	struct inode *inode;
	40	int ret;
	41
	42	inode = iget_locked(sb, ino);
	43	if (!inode)
	44	return ERR_PTR(-ENOMEM);
	45	if (!(inode->i_state & I_NEW))
	46	return inode;
	47
	48	ret = diRead(inode);
	49	if (ret < 0) {
	50	iget_failed(inode);
	51	return ERR_PTR(ret);
1da177e4 LT	52	}
	53
	54	if (S_ISREG(inode->i_mode)) {
	55	inode->i_op = &jfs_file_inode_operations;
	56	inode->i_fop = &jfs_file_operations;
	57	inode->i_mapping->a_ops = &jfs_aops;
	58	} else if (S_ISDIR(inode->i_mode)) {
	59	inode->i_op = &jfs_dir_inode_operations;
	60	inode->i_fop = &jfs_dir_operations;
	61	} else if (S_ISLNK(inode->i_mode)) {
	62	if (inode->i_size >= IDATASIZE) {
	63	inode->i_op = &page_symlink_inode_operations;
21fc61c7	64	inode_nohighmem(inode);
1da177e4	65	inode->i_mapping->a_ops = &jfs_aops;
d69e83d9	66	} else {
c7f2e1f0	67	inode->i_op = &jfs_fast_symlink_inode_operations;
ad476fed	68	inode->i_link = JFS_IP(inode)->i_inline;
d69e83d9 DK	69	/*
	70	* The inline data should be null-terminated, but
	71	* don't let on-disk corruption crash the kernel
	72	*/
ad476fed	73	inode->i_link[inode->i_size] = '\0';
d69e83d9	74	}
1da177e4 LT	75	} else {
	76	inode->i_op = &jfs_file_inode_operations;
	77	init_special_inode(inode, inode->i_mode, inode->i_rdev);
	78	}
eab1df71 DH	79	unlock_new_inode(inode);
eab1df71 DH	80	return inode;
1da177e4 LT	81	}
	82
	83	/*
	84	* Workhorse of both fsync & write_inode
	85	*/
	86	int jfs_commit_inode(struct inode *inode, int wait)
	87	{
	88	int rc = 0;
	89	tid_t tid;
	90	static int noisy = 5;
	91
	92	jfs_info("In jfs_commit_inode, inode = 0x%p", inode);
	93
	94	/*
	95	* Don't commit if inode has been committed since last being
	96	* marked dirty, or if it has been deleted.
	97	*/
	98	if (inode->i_nlink == 0 \|\| !test_cflag(COMMIT_Dirty, inode))
	99	return 0;
	100
	101	if (isReadOnly(inode)) {
	102	/* kernel allows writes to devices on read-only
	103	* partitions and may think inode is dirty
	104	*/
	105	if (!special_file(inode->i_mode) && noisy) {
6ed71e98 JP	106	jfs_err("jfs_commit_inode(0x%p) called on read-only volume",
6ed71e98 JP	107	inode);
1da177e4 LT	108	jfs_err("Is remount racy?");
	109	noisy--;
	110	}
	111	return 0;
	112	}
	113
	114	tid = txBegin(inode->i_sb, COMMIT_INODE);
1de87444	115	mutex_lock(&JFS_IP(inode)->commit_mutex);
1da177e4 LT	116
1da177e4 LT	117	/*
1de87444	118	* Retest inode state after taking commit_mutex
1da177e4 LT	119	*/
	120	if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))
	121	rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);
	122
	123	txEnd(tid);
1de87444	124	mutex_unlock(&JFS_IP(inode)->commit_mutex);
1da177e4 LT	125	return rc;
	126	}
	127
a9185b41	128	int jfs_write_inode(struct inode inode, struct writeback_control wbc)
1da177e4	129	{
a9185b41 CH	130	int wait = wbc->sync_mode == WB_SYNC_ALL;
a9185b41 CH	131
73aaa22d	132	if (inode->i_nlink == 0)
1da177e4 LT	133	return 0;
	134	/*
	135	* If COMMIT_DIRTY is not set, the inode isn't really dirty.
	136	* It has been committed since the last change, but was still
	137	* on the dirty inode list.
	138	*/
f7f31adf	139	if (!test_cflag(COMMIT_Dirty, inode)) {
1da177e4 LT	140	/* Make sure committed changes hit the disk */
	141	jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
	142	return 0;
f7f31adf	143	}
1da177e4 LT	144
	145	if (jfs_commit_inode(inode, wait)) {
	146	jfs_err("jfs_write_inode: jfs_commit_inode failed!");
	147	return -EIO;
	148	} else
	149	return 0;
	150	}
	151
62aff86f	152	void jfs_evict_inode(struct inode *inode)
1da177e4	153	{
b3b4a6e3 AV	154	struct jfs_inode_info *ji = JFS_IP(inode);
b3b4a6e3 AV	155
62aff86f	156	jfs_info("In jfs_evict_inode, inode = 0x%p", inode);
1da177e4	157
62aff86f	158	if (!inode->i_nlink && !is_bad_inode(inode)) {
871a2931	159	dquot_initialize(inode);
907f4554	160
62aff86f	161	if (JFS_IP(inode)->fileset == FILESYSTEM_I) {
91b0abe3	162	truncate_inode_pages_final(&inode->i_data);
fef26658	163
62aff86f AV	164	if (test_cflag(COMMIT_Freewmap, inode))
62aff86f AV	165	jfs_free_zero_link(inode);
1da177e4	166
62aff86f	167	diFree(inode);
1da177e4	168
62aff86f AV	169	/*
	170	* Free the inode from the quota allocation.
	171	*/
62aff86f AV	172	dquot_free_inode(inode);
	173	}
	174	} else {
91b0abe3	175	truncate_inode_pages_final(&inode->i_data);
b1b5d7f9	176	}
dbd5768f	177	clear_inode(inode);
62aff86f	178	dquot_drop(inode);
b3b4a6e3 AV	179
	180	BUG_ON(!list_empty(&ji->anon_inode_list));
	181
	182	spin_lock_irq(&ji->ag_lock);
	183	if (ji->active_ag != -1) {
	184	struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
	185	atomic_dec(&bmap->db_active[ji->active_ag]);
	186	ji->active_ag = -1;
	187	}
	188	spin_unlock_irq(&ji->ag_lock);
1da177e4 LT	189	}
1da177e4 LT	190
aa385729	191	void jfs_dirty_inode(struct inode *inode, int flags)
1da177e4 LT	192	{
	193	static int noisy = 5;
	194
	195	if (isReadOnly(inode)) {
	196	if (!special_file(inode->i_mode) && noisy) {
	197	/* kernel allows writes to devices on read-only
	198	* partitions and may try to mark inode dirty
	199	*/
	200	jfs_err("jfs_dirty_inode called on read-only volume");
	201	jfs_err("Is remount racy?");
	202	noisy--;
	203	}
	204	return;
	205	}
	206
	207	set_cflag(COMMIT_Dirty, inode);
	208	}
	209
115ff50b DK	210	int jfs_get_block(struct inode *ip, sector_t lblock,
115ff50b DK	211	struct buffer_head *bh_result, int create)
1da177e4 LT	212	{
	213	s64 lblock64 = lblock;
	214	int rc = 0;
1da177e4 LT	215	xad_t xad;
	216	s64 xaddr;
	217	int xflag;
115ff50b	218	s32 xlen = bh_result->b_size >> ip->i_blkbits;
1da177e4	219
1da177e4 LT	220	/*
	221	* Take appropriate lock on inode
	222	*/
7fab479b	223	if (create)
82d5b9a7	224	IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
7fab479b	225	else
82d5b9a7	226	IREAD_LOCK(ip, RDWRLOCK_NORMAL);
1da177e4 LT	227
1da177e4 LT	228	if (((lblock64 << ip->i_sb->s_blocksize_bits) < ip->i_size) &&
115ff50b	229	(!xtLookup(ip, lblock64, xlen, &xflag, &xaddr, &xlen, 0)) &&
6628465e	230	xaddr) {
1da177e4 LT	231	if (xflag & XAD_NOTRECORDED) {
	232	if (!create)
	233	/*
	234	* Allocated but not recorded, read treats
	235	* this as a hole
	236	*/
	237	goto unlock;
	238	#ifdef _JFS_4K
	239	XADoffset(&xad, lblock64);
	240	XADlength(&xad, xlen);
	241	XADaddress(&xad, xaddr);
	242	#else /* _JFS_4K */
	243	/*
	244	* As long as block size = 4K, this isn't a problem.
	245	* We should mark the whole page not ABNR, but how
	246	* will we know to mark the other blocks BH_New?
	247	*/
	248	BUG();
	249	#endif /* _JFS_4K */
	250	rc = extRecord(ip, &xad);
	251	if (rc)
	252	goto unlock;
	253	set_buffer_new(bh_result);
	254	}
	255
	256	map_bh(bh_result, ip->i_sb, xaddr);
	257	bh_result->b_size = xlen << ip->i_blkbits;
	258	goto unlock;
	259	}
	260	if (!create)
	261	goto unlock;
	262
	263	/*
	264	* Allocate a new block
	265	*/
	266	#ifdef _JFS_4K
	267	if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
	268	goto unlock;
4d81715f	269	rc = extAlloc(ip, xlen, lblock64, &xad, false);
1da177e4 LT	270	if (rc)
	271	goto unlock;
	272
	273	set_buffer_new(bh_result);
	274	map_bh(bh_result, ip->i_sb, addressXAD(&xad));
	275	bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
	276
	277	#else /* _JFS_4K */
	278	/*
	279	* We need to do whatever it takes to keep all but the last buffers
	280	* in 4K pages - see jfs_write.c
	281	*/
	282	BUG();
	283	#endif /* _JFS_4K */
	284
	285	unlock:
	286	/*
	287	* Release lock on inode
	288	*/
7fab479b DK	289	if (create)
	290	IWRITE_UNLOCK(ip);
	291	else
	292	IREAD_UNLOCK(ip);
1da177e4 LT	293	return rc;
	294	}
	295
1da177e4 LT	296	static int jfs_writepage(struct page page, struct writeback_control wbc)
1da177e4 LT	297	{
d5c5f84b	298	return block_write_full_page(page, jfs_get_block, wbc);
1da177e4 LT	299	}
	300
	301	static int jfs_writepages(struct address_space *mapping,
	302	struct writeback_control *wbc)
	303	{
	304	return mpage_writepages(mapping, wbc, jfs_get_block);
	305	}
	306
	307	static int jfs_readpage(struct file file, struct page page)
	308	{
	309	return mpage_readpage(page, jfs_get_block);
	310	}
	311
	312	static int jfs_readpages(struct file file, struct address_space mapping,
	313	struct list_head *pages, unsigned nr_pages)
	314	{
	315	return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
	316	}
	317
86dd07d6 MS	318	static void jfs_write_failed(struct address_space *mapping, loff_t to)
	319	{
	320	struct inode *inode = mapping->host;
	321
	322	if (to > inode->i_size) {
7caef267	323	truncate_pagecache(inode, inode->i_size);
86dd07d6 MS	324	jfs_truncate(inode);
	325	}
	326	}
	327
d5c5f84b NP	328	static int jfs_write_begin(struct file file, struct address_space mapping,
	329	loff_t pos, unsigned len, unsigned flags,
	330	struct page pagep, void fsdata)
1da177e4	331	{
ea0f04e5 CH	332	int ret;
	333
	334	ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata,
d5c5f84b	335	jfs_get_block);
86dd07d6 MS	336	if (unlikely(ret))
86dd07d6 MS	337	jfs_write_failed(mapping, pos + len);
ea0f04e5 CH	338
ea0f04e5 CH	339	return ret;
1da177e4 LT	340	}
	341
	342	static sector_t jfs_bmap(struct address_space *mapping, sector_t block)
	343	{
	344	return generic_block_bmap(mapping, block, jfs_get_block);
	345	}
	346
c8b8e32d	347	static ssize_t jfs_direct_IO(struct kiocb iocb, struct iov_iter iter)
1da177e4 LT	348	{
1da177e4 LT	349	struct file *file = iocb->ki_filp;
86dd07d6	350	struct address_space *mapping = file->f_mapping;
1da177e4	351	struct inode *inode = file->f_mapping->host;
a6cbcd4a	352	size_t count = iov_iter_count(iter);
eafdc7d1	353	ssize_t ret;
1da177e4	354
c8b8e32d	355	ret = blockdev_direct_IO(iocb, inode, iter, jfs_get_block);
eafdc7d1 CH	356
	357	/*
	358	* In case of error extending write may have instantiated a few
	359	* blocks outside i_size. Trim these off again.
	360	*/
6f673763	361	if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) {
eafdc7d1	362	loff_t isize = i_size_read(inode);
c8b8e32d	363	loff_t end = iocb->ki_pos + count;
eafdc7d1 CH	364
eafdc7d1 CH	365	if (end > isize)
86dd07d6	366	jfs_write_failed(mapping, end);
eafdc7d1 CH	367	}
	368
	369	return ret;
1da177e4 LT	370	}
1da177e4 LT	371
f5e54d6e	372	const struct address_space_operations jfs_aops = {
1da177e4 LT	373	.readpage = jfs_readpage,
	374	.readpages = jfs_readpages,
	375	.writepage = jfs_writepage,
	376	.writepages = jfs_writepages,
d5c5f84b	377	.write_begin = jfs_write_begin,
03158cd7	378	.write_end = nobh_write_end,
1da177e4 LT	379	.bmap = jfs_bmap,
	380	.direct_IO = jfs_direct_IO,
	381	};
	382
	383	/*
	384	* Guts of jfs_truncate. Called with locks already held. Can be called
	385	* with directory for truncating directory index table.
	386	*/
	387	void jfs_truncate_nolock(struct inode *ip, loff_t length)
	388	{
	389	loff_t newsize;
	390	tid_t tid;
	391
	392	ASSERT(length >= 0);
	393
	394	if (test_cflag(COMMIT_Nolink, ip)) {
	395	xtTruncate(0, ip, length, COMMIT_WMAP);
	396	return;
	397	}
	398
	399	do {
	400	tid = txBegin(ip->i_sb, 0);
	401
	402	/*
1de87444	403	* The commit_mutex cannot be taken before txBegin.
1da177e4 LT	404	* txBegin may block and there is a chance the inode
	405	* could be marked dirty and need to be committed
	406	* before txBegin unblocks
	407	*/
1de87444	408	mutex_lock(&JFS_IP(ip)->commit_mutex);
1da177e4 LT	409
	410	newsize = xtTruncate(tid, ip, length,
	411	COMMIT_TRUNCATE \| COMMIT_PWMAP);
	412	if (newsize < 0) {
	413	txEnd(tid);
1de87444	414	mutex_unlock(&JFS_IP(ip)->commit_mutex);
1da177e4 LT	415	break;
	416	}
	417
078cd827	418	ip->i_mtime = ip->i_ctime = current_time(ip);
1da177e4 LT	419	mark_inode_dirty(ip);
	420
	421	txCommit(tid, 1, &ip, 0);
	422	txEnd(tid);
1de87444	423	mutex_unlock(&JFS_IP(ip)->commit_mutex);
1da177e4 LT	424	} while (newsize > length); /* Truncate isn't always atomic */
	425	}
	426
	427	void jfs_truncate(struct inode *ip)
	428	{
	429	jfs_info("jfs_truncate: size = 0x%lx", (ulong) ip->i_size);
	430
03158cd7	431	nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block);
1da177e4	432
82d5b9a7	433	IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
1da177e4 LT	434	jfs_truncate_nolock(ip, ip->i_size);
	435	IWRITE_UNLOCK(ip);
	436	}