| /* -*- mode: c; c-basic-offset: 8; -*- | 
 |  * vim: noexpandtab sw=8 ts=8 sts=0: | 
 |  * | 
 |  * Copyright (C) 2002, 2004 Oracle.  All rights reserved. | 
 |  * | 
 |  * 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 021110-1307, USA. | 
 |  */ | 
 |  | 
 | #include <linux/fs.h> | 
 | #include <linux/slab.h> | 
 | #include <linux/highmem.h> | 
 | #include <linux/pagemap.h> | 
 | #include <asm/byteorder.h> | 
 | #include <linux/swap.h> | 
 | #include <linux/pipe_fs_i.h> | 
 | #include <linux/mpage.h> | 
 | #include <linux/quotaops.h> | 
 | #include <linux/blkdev.h> | 
 | #include <linux/uio.h> | 
 |  | 
 | #include <cluster/masklog.h> | 
 |  | 
 | #include "ocfs2.h" | 
 |  | 
 | #include "alloc.h" | 
 | #include "aops.h" | 
 | #include "dlmglue.h" | 
 | #include "extent_map.h" | 
 | #include "file.h" | 
 | #include "inode.h" | 
 | #include "journal.h" | 
 | #include "suballoc.h" | 
 | #include "super.h" | 
 | #include "symlink.h" | 
 | #include "refcounttree.h" | 
 | #include "ocfs2_trace.h" | 
 |  | 
 | #include "buffer_head_io.h" | 
 | #include "dir.h" | 
 | #include "namei.h" | 
 | #include "sysfile.h" | 
 |  | 
 | static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, | 
 | 				   struct buffer_head *bh_result, int create) | 
 | { | 
 | 	int err = -EIO; | 
 | 	int status; | 
 | 	struct ocfs2_dinode *fe = NULL; | 
 | 	struct buffer_head *bh = NULL; | 
 | 	struct buffer_head *buffer_cache_bh = NULL; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 | 	void *kaddr; | 
 |  | 
 | 	trace_ocfs2_symlink_get_block( | 
 | 			(unsigned long long)OCFS2_I(inode)->ip_blkno, | 
 | 			(unsigned long long)iblock, bh_result, create); | 
 |  | 
 | 	BUG_ON(ocfs2_inode_is_fast_symlink(inode)); | 
 |  | 
 | 	if ((iblock << inode->i_sb->s_blocksize_bits) > PATH_MAX + 1) { | 
 | 		mlog(ML_ERROR, "block offset > PATH_MAX: %llu", | 
 | 		     (unsigned long long)iblock); | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	status = ocfs2_read_inode_block(inode, &bh); | 
 | 	if (status < 0) { | 
 | 		mlog_errno(status); | 
 | 		goto bail; | 
 | 	} | 
 | 	fe = (struct ocfs2_dinode *) bh->b_data; | 
 |  | 
 | 	if ((u64)iblock >= ocfs2_clusters_to_blocks(inode->i_sb, | 
 | 						    le32_to_cpu(fe->i_clusters))) { | 
 | 		err = -ENOMEM; | 
 | 		mlog(ML_ERROR, "block offset is outside the allocated size: " | 
 | 		     "%llu\n", (unsigned long long)iblock); | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	/* We don't use the page cache to create symlink data, so if | 
 | 	 * need be, copy it over from the buffer cache. */ | 
 | 	if (!buffer_uptodate(bh_result) && ocfs2_inode_is_new(inode)) { | 
 | 		u64 blkno = le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + | 
 | 			    iblock; | 
 | 		buffer_cache_bh = sb_getblk(osb->sb, blkno); | 
 | 		if (!buffer_cache_bh) { | 
 | 			err = -ENOMEM; | 
 | 			mlog(ML_ERROR, "couldn't getblock for symlink!\n"); | 
 | 			goto bail; | 
 | 		} | 
 |  | 
 | 		/* we haven't locked out transactions, so a commit | 
 | 		 * could've happened. Since we've got a reference on | 
 | 		 * the bh, even if it commits while we're doing the | 
 | 		 * copy, the data is still good. */ | 
 | 		if (buffer_jbd(buffer_cache_bh) | 
 | 		    && ocfs2_inode_is_new(inode)) { | 
 | 			kaddr = kmap_atomic(bh_result->b_page); | 
 | 			if (!kaddr) { | 
 | 				mlog(ML_ERROR, "couldn't kmap!\n"); | 
 | 				goto bail; | 
 | 			} | 
 | 			memcpy(kaddr + (bh_result->b_size * iblock), | 
 | 			       buffer_cache_bh->b_data, | 
 | 			       bh_result->b_size); | 
 | 			kunmap_atomic(kaddr); | 
 | 			set_buffer_uptodate(bh_result); | 
 | 		} | 
 | 		brelse(buffer_cache_bh); | 
 | 	} | 
 |  | 
 | 	map_bh(bh_result, inode->i_sb, | 
 | 	       le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + iblock); | 
 |  | 
 | 	err = 0; | 
 |  | 
 | bail: | 
 | 	brelse(bh); | 
 |  | 
 | 	return err; | 
 | } | 
 |  | 
 | static int ocfs2_lock_get_block(struct inode *inode, sector_t iblock, | 
 | 		    struct buffer_head *bh_result, int create) | 
 | { | 
 | 	int ret = 0; | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 |  | 
 | 	down_read(&oi->ip_alloc_sem); | 
 | 	ret = ocfs2_get_block(inode, iblock, bh_result, create); | 
 | 	up_read(&oi->ip_alloc_sem); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | int ocfs2_get_block(struct inode *inode, sector_t iblock, | 
 | 		    struct buffer_head *bh_result, int create) | 
 | { | 
 | 	int err = 0; | 
 | 	unsigned int ext_flags; | 
 | 	u64 max_blocks = bh_result->b_size >> inode->i_blkbits; | 
 | 	u64 p_blkno, count, past_eof; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 |  | 
 | 	trace_ocfs2_get_block((unsigned long long)OCFS2_I(inode)->ip_blkno, | 
 | 			      (unsigned long long)iblock, bh_result, create); | 
 |  | 
 | 	if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE) | 
 | 		mlog(ML_NOTICE, "get_block on system inode 0x%p (%lu)\n", | 
 | 		     inode, inode->i_ino); | 
 |  | 
 | 	if (S_ISLNK(inode->i_mode)) { | 
 | 		/* this always does I/O for some reason. */ | 
 | 		err = ocfs2_symlink_get_block(inode, iblock, bh_result, create); | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, &count, | 
 | 					  &ext_flags); | 
 | 	if (err) { | 
 | 		mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, " | 
 | 		     "%llu, NULL)\n", err, inode, (unsigned long long)iblock, | 
 | 		     (unsigned long long)p_blkno); | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	if (max_blocks < count) | 
 | 		count = max_blocks; | 
 |  | 
 | 	/* | 
 | 	 * ocfs2 never allocates in this function - the only time we | 
 | 	 * need to use BH_New is when we're extending i_size on a file | 
 | 	 * system which doesn't support holes, in which case BH_New | 
 | 	 * allows __block_write_begin() to zero. | 
 | 	 * | 
 | 	 * If we see this on a sparse file system, then a truncate has | 
 | 	 * raced us and removed the cluster. In this case, we clear | 
 | 	 * the buffers dirty and uptodate bits and let the buffer code | 
 | 	 * ignore it as a hole. | 
 | 	 */ | 
 | 	if (create && p_blkno == 0 && ocfs2_sparse_alloc(osb)) { | 
 | 		clear_buffer_dirty(bh_result); | 
 | 		clear_buffer_uptodate(bh_result); | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	/* Treat the unwritten extent as a hole for zeroing purposes. */ | 
 | 	if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN)) | 
 | 		map_bh(bh_result, inode->i_sb, p_blkno); | 
 |  | 
 | 	bh_result->b_size = count << inode->i_blkbits; | 
 |  | 
 | 	if (!ocfs2_sparse_alloc(osb)) { | 
 | 		if (p_blkno == 0) { | 
 | 			err = -EIO; | 
 | 			mlog(ML_ERROR, | 
 | 			     "iblock = %llu p_blkno = %llu blkno=(%llu)\n", | 
 | 			     (unsigned long long)iblock, | 
 | 			     (unsigned long long)p_blkno, | 
 | 			     (unsigned long long)OCFS2_I(inode)->ip_blkno); | 
 | 			mlog(ML_ERROR, "Size %llu, clusters %u\n", (unsigned long long)i_size_read(inode), OCFS2_I(inode)->ip_clusters); | 
 | 			dump_stack(); | 
 | 			goto bail; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode)); | 
 |  | 
 | 	trace_ocfs2_get_block_end((unsigned long long)OCFS2_I(inode)->ip_blkno, | 
 | 				  (unsigned long long)past_eof); | 
 | 	if (create && (iblock >= past_eof)) | 
 | 		set_buffer_new(bh_result); | 
 |  | 
 | bail: | 
 | 	if (err < 0) | 
 | 		err = -EIO; | 
 |  | 
 | 	return err; | 
 | } | 
 |  | 
 | int ocfs2_read_inline_data(struct inode *inode, struct page *page, | 
 | 			   struct buffer_head *di_bh) | 
 | { | 
 | 	void *kaddr; | 
 | 	loff_t size; | 
 | 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; | 
 |  | 
 | 	if (!(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL)) { | 
 | 		ocfs2_error(inode->i_sb, "Inode %llu lost inline data flag\n", | 
 | 			    (unsigned long long)OCFS2_I(inode)->ip_blkno); | 
 | 		return -EROFS; | 
 | 	} | 
 |  | 
 | 	size = i_size_read(inode); | 
 |  | 
 | 	if (size > PAGE_SIZE || | 
 | 	    size > ocfs2_max_inline_data_with_xattr(inode->i_sb, di)) { | 
 | 		ocfs2_error(inode->i_sb, | 
 | 			    "Inode %llu has with inline data has bad size: %Lu\n", | 
 | 			    (unsigned long long)OCFS2_I(inode)->ip_blkno, | 
 | 			    (unsigned long long)size); | 
 | 		return -EROFS; | 
 | 	} | 
 |  | 
 | 	kaddr = kmap_atomic(page); | 
 | 	if (size) | 
 | 		memcpy(kaddr, di->id2.i_data.id_data, size); | 
 | 	/* Clear the remaining part of the page */ | 
 | 	memset(kaddr + size, 0, PAGE_SIZE - size); | 
 | 	flush_dcache_page(page); | 
 | 	kunmap_atomic(kaddr); | 
 |  | 
 | 	SetPageUptodate(page); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int ocfs2_readpage_inline(struct inode *inode, struct page *page) | 
 | { | 
 | 	int ret; | 
 | 	struct buffer_head *di_bh = NULL; | 
 |  | 
 | 	BUG_ON(!PageLocked(page)); | 
 | 	BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)); | 
 |  | 
 | 	ret = ocfs2_read_inode_block(inode, &di_bh); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_read_inline_data(inode, page, di_bh); | 
 | out: | 
 | 	unlock_page(page); | 
 |  | 
 | 	brelse(di_bh); | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int ocfs2_readpage(struct file *file, struct page *page) | 
 | { | 
 | 	struct inode *inode = page->mapping->host; | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 | 	loff_t start = (loff_t)page->index << PAGE_SHIFT; | 
 | 	int ret, unlock = 1; | 
 |  | 
 | 	trace_ocfs2_readpage((unsigned long long)oi->ip_blkno, | 
 | 			     (page ? page->index : 0)); | 
 |  | 
 | 	ret = ocfs2_inode_lock_with_page(inode, NULL, 0, page); | 
 | 	if (ret != 0) { | 
 | 		if (ret == AOP_TRUNCATED_PAGE) | 
 | 			unlock = 0; | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	if (down_read_trylock(&oi->ip_alloc_sem) == 0) { | 
 | 		/* | 
 | 		 * Unlock the page and cycle ip_alloc_sem so that we don't | 
 | 		 * busyloop waiting for ip_alloc_sem to unlock | 
 | 		 */ | 
 | 		ret = AOP_TRUNCATED_PAGE; | 
 | 		unlock_page(page); | 
 | 		unlock = 0; | 
 | 		down_read(&oi->ip_alloc_sem); | 
 | 		up_read(&oi->ip_alloc_sem); | 
 | 		goto out_inode_unlock; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * i_size might have just been updated as we grabed the meta lock.  We | 
 | 	 * might now be discovering a truncate that hit on another node. | 
 | 	 * block_read_full_page->get_block freaks out if it is asked to read | 
 | 	 * beyond the end of a file, so we check here.  Callers | 
 | 	 * (generic_file_read, vm_ops->fault) are clever enough to check i_size | 
 | 	 * and notice that the page they just read isn't needed. | 
 | 	 * | 
 | 	 * XXX sys_readahead() seems to get that wrong? | 
 | 	 */ | 
 | 	if (start >= i_size_read(inode)) { | 
 | 		zero_user(page, 0, PAGE_SIZE); | 
 | 		SetPageUptodate(page); | 
 | 		ret = 0; | 
 | 		goto out_alloc; | 
 | 	} | 
 |  | 
 | 	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) | 
 | 		ret = ocfs2_readpage_inline(inode, page); | 
 | 	else | 
 | 		ret = block_read_full_page(page, ocfs2_get_block); | 
 | 	unlock = 0; | 
 |  | 
 | out_alloc: | 
 | 	up_read(&oi->ip_alloc_sem); | 
 | out_inode_unlock: | 
 | 	ocfs2_inode_unlock(inode, 0); | 
 | out: | 
 | 	if (unlock) | 
 | 		unlock_page(page); | 
 | 	return ret; | 
 | } | 
 |  | 
 | /* | 
 |  * This is used only for read-ahead. Failures or difficult to handle | 
 |  * situations are safe to ignore. | 
 |  * | 
 |  * Right now, we don't bother with BH_Boundary - in-inode extent lists | 
 |  * are quite large (243 extents on 4k blocks), so most inodes don't | 
 |  * grow out to a tree. If need be, detecting boundary extents could | 
 |  * trivially be added in a future version of ocfs2_get_block(). | 
 |  */ | 
 | static int ocfs2_readpages(struct file *filp, struct address_space *mapping, | 
 | 			   struct list_head *pages, unsigned nr_pages) | 
 | { | 
 | 	int ret, err = -EIO; | 
 | 	struct inode *inode = mapping->host; | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 | 	loff_t start; | 
 | 	struct page *last; | 
 |  | 
 | 	/* | 
 | 	 * Use the nonblocking flag for the dlm code to avoid page | 
 | 	 * lock inversion, but don't bother with retrying. | 
 | 	 */ | 
 | 	ret = ocfs2_inode_lock_full(inode, NULL, 0, OCFS2_LOCK_NONBLOCK); | 
 | 	if (ret) | 
 | 		return err; | 
 |  | 
 | 	if (down_read_trylock(&oi->ip_alloc_sem) == 0) { | 
 | 		ocfs2_inode_unlock(inode, 0); | 
 | 		return err; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * Don't bother with inline-data. There isn't anything | 
 | 	 * to read-ahead in that case anyway... | 
 | 	 */ | 
 | 	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) | 
 | 		goto out_unlock; | 
 |  | 
 | 	/* | 
 | 	 * Check whether a remote node truncated this file - we just | 
 | 	 * drop out in that case as it's not worth handling here. | 
 | 	 */ | 
 | 	last = list_entry(pages->prev, struct page, lru); | 
 | 	start = (loff_t)last->index << PAGE_SHIFT; | 
 | 	if (start >= i_size_read(inode)) | 
 | 		goto out_unlock; | 
 |  | 
 | 	err = mpage_readpages(mapping, pages, nr_pages, ocfs2_get_block); | 
 |  | 
 | out_unlock: | 
 | 	up_read(&oi->ip_alloc_sem); | 
 | 	ocfs2_inode_unlock(inode, 0); | 
 |  | 
 | 	return err; | 
 | } | 
 |  | 
 | /* Note: Because we don't support holes, our allocation has | 
 |  * already happened (allocation writes zeros to the file data) | 
 |  * so we don't have to worry about ordered writes in | 
 |  * ocfs2_writepage. | 
 |  * | 
 |  * ->writepage is called during the process of invalidating the page cache | 
 |  * during blocked lock processing.  It can't block on any cluster locks | 
 |  * to during block mapping.  It's relying on the fact that the block | 
 |  * mapping can't have disappeared under the dirty pages that it is | 
 |  * being asked to write back. | 
 |  */ | 
 | static int ocfs2_writepage(struct page *page, struct writeback_control *wbc) | 
 | { | 
 | 	trace_ocfs2_writepage( | 
 | 		(unsigned long long)OCFS2_I(page->mapping->host)->ip_blkno, | 
 | 		page->index); | 
 |  | 
 | 	return block_write_full_page(page, ocfs2_get_block, wbc); | 
 | } | 
 |  | 
 | /* Taken from ext3. We don't necessarily need the full blown | 
 |  * functionality yet, but IMHO it's better to cut and paste the whole | 
 |  * thing so we can avoid introducing our own bugs (and easily pick up | 
 |  * their fixes when they happen) --Mark */ | 
 | int walk_page_buffers(	handle_t *handle, | 
 | 			struct buffer_head *head, | 
 | 			unsigned from, | 
 | 			unsigned to, | 
 | 			int *partial, | 
 | 			int (*fn)(	handle_t *handle, | 
 | 					struct buffer_head *bh)) | 
 | { | 
 | 	struct buffer_head *bh; | 
 | 	unsigned block_start, block_end; | 
 | 	unsigned blocksize = head->b_size; | 
 | 	int err, ret = 0; | 
 | 	struct buffer_head *next; | 
 |  | 
 | 	for (	bh = head, block_start = 0; | 
 | 		ret == 0 && (bh != head || !block_start); | 
 | 	    	block_start = block_end, bh = next) | 
 | 	{ | 
 | 		next = bh->b_this_page; | 
 | 		block_end = block_start + blocksize; | 
 | 		if (block_end <= from || block_start >= to) { | 
 | 			if (partial && !buffer_uptodate(bh)) | 
 | 				*partial = 1; | 
 | 			continue; | 
 | 		} | 
 | 		err = (*fn)(handle, bh); | 
 | 		if (!ret) | 
 | 			ret = err; | 
 | 	} | 
 | 	return ret; | 
 | } | 
 |  | 
 | static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block) | 
 | { | 
 | 	sector_t status; | 
 | 	u64 p_blkno = 0; | 
 | 	int err = 0; | 
 | 	struct inode *inode = mapping->host; | 
 |  | 
 | 	trace_ocfs2_bmap((unsigned long long)OCFS2_I(inode)->ip_blkno, | 
 | 			 (unsigned long long)block); | 
 |  | 
 | 	/* | 
 | 	 * The swap code (ab-)uses ->bmap to get a block mapping and then | 
 | 	 * bypasseѕ the file system for actual I/O.  We really can't allow | 
 | 	 * that on refcounted inodes, so we have to skip out here.  And yes, | 
 | 	 * 0 is the magic code for a bmap error.. | 
 | 	 */ | 
 | 	if (ocfs2_is_refcount_inode(inode)) | 
 | 		return 0; | 
 |  | 
 | 	/* We don't need to lock journal system files, since they aren't | 
 | 	 * accessed concurrently from multiple nodes. | 
 | 	 */ | 
 | 	if (!INODE_JOURNAL(inode)) { | 
 | 		err = ocfs2_inode_lock(inode, NULL, 0); | 
 | 		if (err) { | 
 | 			if (err != -ENOENT) | 
 | 				mlog_errno(err); | 
 | 			goto bail; | 
 | 		} | 
 | 		down_read(&OCFS2_I(inode)->ip_alloc_sem); | 
 | 	} | 
 |  | 
 | 	if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)) | 
 | 		err = ocfs2_extent_map_get_blocks(inode, block, &p_blkno, NULL, | 
 | 						  NULL); | 
 |  | 
 | 	if (!INODE_JOURNAL(inode)) { | 
 | 		up_read(&OCFS2_I(inode)->ip_alloc_sem); | 
 | 		ocfs2_inode_unlock(inode, 0); | 
 | 	} | 
 |  | 
 | 	if (err) { | 
 | 		mlog(ML_ERROR, "get_blocks() failed, block = %llu\n", | 
 | 		     (unsigned long long)block); | 
 | 		mlog_errno(err); | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | bail: | 
 | 	status = err ? 0 : p_blkno; | 
 |  | 
 | 	return status; | 
 | } | 
 |  | 
 | static int ocfs2_releasepage(struct page *page, gfp_t wait) | 
 | { | 
 | 	if (!page_has_buffers(page)) | 
 | 		return 0; | 
 | 	return try_to_free_buffers(page); | 
 | } | 
 |  | 
 | static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb, | 
 | 					    u32 cpos, | 
 | 					    unsigned int *start, | 
 | 					    unsigned int *end) | 
 | { | 
 | 	unsigned int cluster_start = 0, cluster_end = PAGE_SIZE; | 
 |  | 
 | 	if (unlikely(PAGE_SHIFT > osb->s_clustersize_bits)) { | 
 | 		unsigned int cpp; | 
 |  | 
 | 		cpp = 1 << (PAGE_SHIFT - osb->s_clustersize_bits); | 
 |  | 
 | 		cluster_start = cpos % cpp; | 
 | 		cluster_start = cluster_start << osb->s_clustersize_bits; | 
 |  | 
 | 		cluster_end = cluster_start + osb->s_clustersize; | 
 | 	} | 
 |  | 
 | 	BUG_ON(cluster_start > PAGE_SIZE); | 
 | 	BUG_ON(cluster_end > PAGE_SIZE); | 
 |  | 
 | 	if (start) | 
 | 		*start = cluster_start; | 
 | 	if (end) | 
 | 		*end = cluster_end; | 
 | } | 
 |  | 
 | /* | 
 |  * 'from' and 'to' are the region in the page to avoid zeroing. | 
 |  * | 
 |  * If pagesize > clustersize, this function will avoid zeroing outside | 
 |  * of the cluster boundary. | 
 |  * | 
 |  * from == to == 0 is code for "zero the entire cluster region" | 
 |  */ | 
 | static void ocfs2_clear_page_regions(struct page *page, | 
 | 				     struct ocfs2_super *osb, u32 cpos, | 
 | 				     unsigned from, unsigned to) | 
 | { | 
 | 	void *kaddr; | 
 | 	unsigned int cluster_start, cluster_end; | 
 |  | 
 | 	ocfs2_figure_cluster_boundaries(osb, cpos, &cluster_start, &cluster_end); | 
 |  | 
 | 	kaddr = kmap_atomic(page); | 
 |  | 
 | 	if (from || to) { | 
 | 		if (from > cluster_start) | 
 | 			memset(kaddr + cluster_start, 0, from - cluster_start); | 
 | 		if (to < cluster_end) | 
 | 			memset(kaddr + to, 0, cluster_end - to); | 
 | 	} else { | 
 | 		memset(kaddr + cluster_start, 0, cluster_end - cluster_start); | 
 | 	} | 
 |  | 
 | 	kunmap_atomic(kaddr); | 
 | } | 
 |  | 
 | /* | 
 |  * Nonsparse file systems fully allocate before we get to the write | 
 |  * code. This prevents ocfs2_write() from tagging the write as an | 
 |  * allocating one, which means ocfs2_map_page_blocks() might try to | 
 |  * read-in the blocks at the tail of our file. Avoid reading them by | 
 |  * testing i_size against each block offset. | 
 |  */ | 
 | static int ocfs2_should_read_blk(struct inode *inode, struct page *page, | 
 | 				 unsigned int block_start) | 
 | { | 
 | 	u64 offset = page_offset(page) + block_start; | 
 |  | 
 | 	if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) | 
 | 		return 1; | 
 |  | 
 | 	if (i_size_read(inode) > offset) | 
 | 		return 1; | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | /* | 
 |  * Some of this taken from __block_write_begin(). We already have our | 
 |  * mapping by now though, and the entire write will be allocating or | 
 |  * it won't, so not much need to use BH_New. | 
 |  * | 
 |  * This will also skip zeroing, which is handled externally. | 
 |  */ | 
 | int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno, | 
 | 			  struct inode *inode, unsigned int from, | 
 | 			  unsigned int to, int new) | 
 | { | 
 | 	int ret = 0; | 
 | 	struct buffer_head *head, *bh, *wait[2], **wait_bh = wait; | 
 | 	unsigned int block_end, block_start; | 
 | 	unsigned int bsize = i_blocksize(inode); | 
 |  | 
 | 	if (!page_has_buffers(page)) | 
 | 		create_empty_buffers(page, bsize, 0); | 
 |  | 
 | 	head = page_buffers(page); | 
 | 	for (bh = head, block_start = 0; bh != head || !block_start; | 
 | 	     bh = bh->b_this_page, block_start += bsize) { | 
 | 		block_end = block_start + bsize; | 
 |  | 
 | 		clear_buffer_new(bh); | 
 |  | 
 | 		/* | 
 | 		 * Ignore blocks outside of our i/o range - | 
 | 		 * they may belong to unallocated clusters. | 
 | 		 */ | 
 | 		if (block_start >= to || block_end <= from) { | 
 | 			if (PageUptodate(page)) | 
 | 				set_buffer_uptodate(bh); | 
 | 			continue; | 
 | 		} | 
 |  | 
 | 		/* | 
 | 		 * For an allocating write with cluster size >= page | 
 | 		 * size, we always write the entire page. | 
 | 		 */ | 
 | 		if (new) | 
 | 			set_buffer_new(bh); | 
 |  | 
 | 		if (!buffer_mapped(bh)) { | 
 | 			map_bh(bh, inode->i_sb, *p_blkno); | 
 | 			clean_bdev_bh_alias(bh); | 
 | 		} | 
 |  | 
 | 		if (PageUptodate(page)) { | 
 | 			if (!buffer_uptodate(bh)) | 
 | 				set_buffer_uptodate(bh); | 
 | 		} else if (!buffer_uptodate(bh) && !buffer_delay(bh) && | 
 | 			   !buffer_new(bh) && | 
 | 			   ocfs2_should_read_blk(inode, page, block_start) && | 
 | 			   (block_start < from || block_end > to)) { | 
 | 			ll_rw_block(REQ_OP_READ, 0, 1, &bh); | 
 | 			*wait_bh++=bh; | 
 | 		} | 
 |  | 
 | 		*p_blkno = *p_blkno + 1; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * If we issued read requests - let them complete. | 
 | 	 */ | 
 | 	while(wait_bh > wait) { | 
 | 		wait_on_buffer(*--wait_bh); | 
 | 		if (!buffer_uptodate(*wait_bh)) | 
 | 			ret = -EIO; | 
 | 	} | 
 |  | 
 | 	if (ret == 0 || !new) | 
 | 		return ret; | 
 |  | 
 | 	/* | 
 | 	 * If we get -EIO above, zero out any newly allocated blocks | 
 | 	 * to avoid exposing stale data. | 
 | 	 */ | 
 | 	bh = head; | 
 | 	block_start = 0; | 
 | 	do { | 
 | 		block_end = block_start + bsize; | 
 | 		if (block_end <= from) | 
 | 			goto next_bh; | 
 | 		if (block_start >= to) | 
 | 			break; | 
 |  | 
 | 		zero_user(page, block_start, bh->b_size); | 
 | 		set_buffer_uptodate(bh); | 
 | 		mark_buffer_dirty(bh); | 
 |  | 
 | next_bh: | 
 | 		block_start = block_end; | 
 | 		bh = bh->b_this_page; | 
 | 	} while (bh != head); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | #if (PAGE_SIZE >= OCFS2_MAX_CLUSTERSIZE) | 
 | #define OCFS2_MAX_CTXT_PAGES	1 | 
 | #else | 
 | #define OCFS2_MAX_CTXT_PAGES	(OCFS2_MAX_CLUSTERSIZE / PAGE_SIZE) | 
 | #endif | 
 |  | 
 | #define OCFS2_MAX_CLUSTERS_PER_PAGE	(PAGE_SIZE / OCFS2_MIN_CLUSTERSIZE) | 
 |  | 
 | struct ocfs2_unwritten_extent { | 
 | 	struct list_head	ue_node; | 
 | 	struct list_head	ue_ip_node; | 
 | 	u32			ue_cpos; | 
 | 	u32			ue_phys; | 
 | }; | 
 |  | 
 | /* | 
 |  * Describe the state of a single cluster to be written to. | 
 |  */ | 
 | struct ocfs2_write_cluster_desc { | 
 | 	u32		c_cpos; | 
 | 	u32		c_phys; | 
 | 	/* | 
 | 	 * Give this a unique field because c_phys eventually gets | 
 | 	 * filled. | 
 | 	 */ | 
 | 	unsigned	c_new; | 
 | 	unsigned	c_clear_unwritten; | 
 | 	unsigned	c_needs_zero; | 
 | }; | 
 |  | 
 | struct ocfs2_write_ctxt { | 
 | 	/* Logical cluster position / len of write */ | 
 | 	u32				w_cpos; | 
 | 	u32				w_clen; | 
 |  | 
 | 	/* First cluster allocated in a nonsparse extend */ | 
 | 	u32				w_first_new_cpos; | 
 |  | 
 | 	/* Type of caller. Must be one of buffer, mmap, direct.  */ | 
 | 	ocfs2_write_type_t		w_type; | 
 |  | 
 | 	struct ocfs2_write_cluster_desc	w_desc[OCFS2_MAX_CLUSTERS_PER_PAGE]; | 
 |  | 
 | 	/* | 
 | 	 * This is true if page_size > cluster_size. | 
 | 	 * | 
 | 	 * It triggers a set of special cases during write which might | 
 | 	 * have to deal with allocating writes to partial pages. | 
 | 	 */ | 
 | 	unsigned int			w_large_pages; | 
 |  | 
 | 	/* | 
 | 	 * Pages involved in this write. | 
 | 	 * | 
 | 	 * w_target_page is the page being written to by the user. | 
 | 	 * | 
 | 	 * w_pages is an array of pages which always contains | 
 | 	 * w_target_page, and in the case of an allocating write with | 
 | 	 * page_size < cluster size, it will contain zero'd and mapped | 
 | 	 * pages adjacent to w_target_page which need to be written | 
 | 	 * out in so that future reads from that region will get | 
 | 	 * zero's. | 
 | 	 */ | 
 | 	unsigned int			w_num_pages; | 
 | 	struct page			*w_pages[OCFS2_MAX_CTXT_PAGES]; | 
 | 	struct page			*w_target_page; | 
 |  | 
 | 	/* | 
 | 	 * w_target_locked is used for page_mkwrite path indicating no unlocking | 
 | 	 * against w_target_page in ocfs2_write_end_nolock. | 
 | 	 */ | 
 | 	unsigned int			w_target_locked:1; | 
 |  | 
 | 	/* | 
 | 	 * ocfs2_write_end() uses this to know what the real range to | 
 | 	 * write in the target should be. | 
 | 	 */ | 
 | 	unsigned int			w_target_from; | 
 | 	unsigned int			w_target_to; | 
 |  | 
 | 	/* | 
 | 	 * We could use journal_current_handle() but this is cleaner, | 
 | 	 * IMHO -Mark | 
 | 	 */ | 
 | 	handle_t			*w_handle; | 
 |  | 
 | 	struct buffer_head		*w_di_bh; | 
 |  | 
 | 	struct ocfs2_cached_dealloc_ctxt w_dealloc; | 
 |  | 
 | 	struct list_head		w_unwritten_list; | 
 | 	unsigned int			w_unwritten_count; | 
 | }; | 
 |  | 
 | void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages) | 
 | { | 
 | 	int i; | 
 |  | 
 | 	for(i = 0; i < num_pages; i++) { | 
 | 		if (pages[i]) { | 
 | 			unlock_page(pages[i]); | 
 | 			mark_page_accessed(pages[i]); | 
 | 			put_page(pages[i]); | 
 | 		} | 
 | 	} | 
 | } | 
 |  | 
 | static void ocfs2_unlock_pages(struct ocfs2_write_ctxt *wc) | 
 | { | 
 | 	int i; | 
 |  | 
 | 	/* | 
 | 	 * w_target_locked is only set to true in the page_mkwrite() case. | 
 | 	 * The intent is to allow us to lock the target page from write_begin() | 
 | 	 * to write_end(). The caller must hold a ref on w_target_page. | 
 | 	 */ | 
 | 	if (wc->w_target_locked) { | 
 | 		BUG_ON(!wc->w_target_page); | 
 | 		for (i = 0; i < wc->w_num_pages; i++) { | 
 | 			if (wc->w_target_page == wc->w_pages[i]) { | 
 | 				wc->w_pages[i] = NULL; | 
 | 				break; | 
 | 			} | 
 | 		} | 
 | 		mark_page_accessed(wc->w_target_page); | 
 | 		put_page(wc->w_target_page); | 
 | 	} | 
 | 	ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages); | 
 | } | 
 |  | 
 | static void ocfs2_free_unwritten_list(struct inode *inode, | 
 | 				 struct list_head *head) | 
 | { | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 | 	struct ocfs2_unwritten_extent *ue = NULL, *tmp = NULL; | 
 |  | 
 | 	list_for_each_entry_safe(ue, tmp, head, ue_node) { | 
 | 		list_del(&ue->ue_node); | 
 | 		spin_lock(&oi->ip_lock); | 
 | 		list_del(&ue->ue_ip_node); | 
 | 		spin_unlock(&oi->ip_lock); | 
 | 		kfree(ue); | 
 | 	} | 
 | } | 
 |  | 
 | static void ocfs2_free_write_ctxt(struct inode *inode, | 
 | 				  struct ocfs2_write_ctxt *wc) | 
 | { | 
 | 	ocfs2_free_unwritten_list(inode, &wc->w_unwritten_list); | 
 | 	ocfs2_unlock_pages(wc); | 
 | 	brelse(wc->w_di_bh); | 
 | 	kfree(wc); | 
 | } | 
 |  | 
 | static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp, | 
 | 				  struct ocfs2_super *osb, loff_t pos, | 
 | 				  unsigned len, ocfs2_write_type_t type, | 
 | 				  struct buffer_head *di_bh) | 
 | { | 
 | 	u32 cend; | 
 | 	struct ocfs2_write_ctxt *wc; | 
 |  | 
 | 	wc = kzalloc(sizeof(struct ocfs2_write_ctxt), GFP_NOFS); | 
 | 	if (!wc) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	wc->w_cpos = pos >> osb->s_clustersize_bits; | 
 | 	wc->w_first_new_cpos = UINT_MAX; | 
 | 	cend = (pos + len - 1) >> osb->s_clustersize_bits; | 
 | 	wc->w_clen = cend - wc->w_cpos + 1; | 
 | 	get_bh(di_bh); | 
 | 	wc->w_di_bh = di_bh; | 
 | 	wc->w_type = type; | 
 |  | 
 | 	if (unlikely(PAGE_SHIFT > osb->s_clustersize_bits)) | 
 | 		wc->w_large_pages = 1; | 
 | 	else | 
 | 		wc->w_large_pages = 0; | 
 |  | 
 | 	ocfs2_init_dealloc_ctxt(&wc->w_dealloc); | 
 | 	INIT_LIST_HEAD(&wc->w_unwritten_list); | 
 |  | 
 | 	*wcp = wc; | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | /* | 
 |  * If a page has any new buffers, zero them out here, and mark them uptodate | 
 |  * and dirty so they'll be written out (in order to prevent uninitialised | 
 |  * block data from leaking). And clear the new bit. | 
 |  */ | 
 | static void ocfs2_zero_new_buffers(struct page *page, unsigned from, unsigned to) | 
 | { | 
 | 	unsigned int block_start, block_end; | 
 | 	struct buffer_head *head, *bh; | 
 |  | 
 | 	BUG_ON(!PageLocked(page)); | 
 | 	if (!page_has_buffers(page)) | 
 | 		return; | 
 |  | 
 | 	bh = head = page_buffers(page); | 
 | 	block_start = 0; | 
 | 	do { | 
 | 		block_end = block_start + bh->b_size; | 
 |  | 
 | 		if (buffer_new(bh)) { | 
 | 			if (block_end > from && block_start < to) { | 
 | 				if (!PageUptodate(page)) { | 
 | 					unsigned start, end; | 
 |  | 
 | 					start = max(from, block_start); | 
 | 					end = min(to, block_end); | 
 |  | 
 | 					zero_user_segment(page, start, end); | 
 | 					set_buffer_uptodate(bh); | 
 | 				} | 
 |  | 
 | 				clear_buffer_new(bh); | 
 | 				mark_buffer_dirty(bh); | 
 | 			} | 
 | 		} | 
 |  | 
 | 		block_start = block_end; | 
 | 		bh = bh->b_this_page; | 
 | 	} while (bh != head); | 
 | } | 
 |  | 
 | /* | 
 |  * Only called when we have a failure during allocating write to write | 
 |  * zero's to the newly allocated region. | 
 |  */ | 
 | static void ocfs2_write_failure(struct inode *inode, | 
 | 				struct ocfs2_write_ctxt *wc, | 
 | 				loff_t user_pos, unsigned user_len) | 
 | { | 
 | 	int i; | 
 | 	unsigned from = user_pos & (PAGE_SIZE - 1), | 
 | 		to = user_pos + user_len; | 
 | 	struct page *tmppage; | 
 |  | 
 | 	if (wc->w_target_page) | 
 | 		ocfs2_zero_new_buffers(wc->w_target_page, from, to); | 
 |  | 
 | 	for(i = 0; i < wc->w_num_pages; i++) { | 
 | 		tmppage = wc->w_pages[i]; | 
 |  | 
 | 		if (tmppage && page_has_buffers(tmppage)) { | 
 | 			if (ocfs2_should_order_data(inode)) | 
 | 				ocfs2_jbd2_file_inode(wc->w_handle, inode); | 
 |  | 
 | 			block_commit_write(tmppage, from, to); | 
 | 		} | 
 | 	} | 
 | } | 
 |  | 
 | static int ocfs2_prepare_page_for_write(struct inode *inode, u64 *p_blkno, | 
 | 					struct ocfs2_write_ctxt *wc, | 
 | 					struct page *page, u32 cpos, | 
 | 					loff_t user_pos, unsigned user_len, | 
 | 					int new) | 
 | { | 
 | 	int ret; | 
 | 	unsigned int map_from = 0, map_to = 0; | 
 | 	unsigned int cluster_start, cluster_end; | 
 | 	unsigned int user_data_from = 0, user_data_to = 0; | 
 |  | 
 | 	ocfs2_figure_cluster_boundaries(OCFS2_SB(inode->i_sb), cpos, | 
 | 					&cluster_start, &cluster_end); | 
 |  | 
 | 	/* treat the write as new if the a hole/lseek spanned across | 
 | 	 * the page boundary. | 
 | 	 */ | 
 | 	new = new | ((i_size_read(inode) <= page_offset(page)) && | 
 | 			(page_offset(page) <= user_pos)); | 
 |  | 
 | 	if (page == wc->w_target_page) { | 
 | 		map_from = user_pos & (PAGE_SIZE - 1); | 
 | 		map_to = map_from + user_len; | 
 |  | 
 | 		if (new) | 
 | 			ret = ocfs2_map_page_blocks(page, p_blkno, inode, | 
 | 						    cluster_start, cluster_end, | 
 | 						    new); | 
 | 		else | 
 | 			ret = ocfs2_map_page_blocks(page, p_blkno, inode, | 
 | 						    map_from, map_to, new); | 
 | 		if (ret) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 |  | 
 | 		user_data_from = map_from; | 
 | 		user_data_to = map_to; | 
 | 		if (new) { | 
 | 			map_from = cluster_start; | 
 | 			map_to = cluster_end; | 
 | 		} | 
 | 	} else { | 
 | 		/* | 
 | 		 * If we haven't allocated the new page yet, we | 
 | 		 * shouldn't be writing it out without copying user | 
 | 		 * data. This is likely a math error from the caller. | 
 | 		 */ | 
 | 		BUG_ON(!new); | 
 |  | 
 | 		map_from = cluster_start; | 
 | 		map_to = cluster_end; | 
 |  | 
 | 		ret = ocfs2_map_page_blocks(page, p_blkno, inode, | 
 | 					    cluster_start, cluster_end, new); | 
 | 		if (ret) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * Parts of newly allocated pages need to be zero'd. | 
 | 	 * | 
 | 	 * Above, we have also rewritten 'to' and 'from' - as far as | 
 | 	 * the rest of the function is concerned, the entire cluster | 
 | 	 * range inside of a page needs to be written. | 
 | 	 * | 
 | 	 * We can skip this if the page is up to date - it's already | 
 | 	 * been zero'd from being read in as a hole. | 
 | 	 */ | 
 | 	if (new && !PageUptodate(page)) | 
 | 		ocfs2_clear_page_regions(page, OCFS2_SB(inode->i_sb), | 
 | 					 cpos, user_data_from, user_data_to); | 
 |  | 
 | 	flush_dcache_page(page); | 
 |  | 
 | out: | 
 | 	return ret; | 
 | } | 
 |  | 
 | /* | 
 |  * This function will only grab one clusters worth of pages. | 
 |  */ | 
 | static int ocfs2_grab_pages_for_write(struct address_space *mapping, | 
 | 				      struct ocfs2_write_ctxt *wc, | 
 | 				      u32 cpos, loff_t user_pos, | 
 | 				      unsigned user_len, int new, | 
 | 				      struct page *mmap_page) | 
 | { | 
 | 	int ret = 0, i; | 
 | 	unsigned long start, target_index, end_index, index; | 
 | 	struct inode *inode = mapping->host; | 
 | 	loff_t last_byte; | 
 |  | 
 | 	target_index = user_pos >> PAGE_SHIFT; | 
 |  | 
 | 	/* | 
 | 	 * Figure out how many pages we'll be manipulating here. For | 
 | 	 * non allocating write, we just change the one | 
 | 	 * page. Otherwise, we'll need a whole clusters worth.  If we're | 
 | 	 * writing past i_size, we only need enough pages to cover the | 
 | 	 * last page of the write. | 
 | 	 */ | 
 | 	if (new) { | 
 | 		wc->w_num_pages = ocfs2_pages_per_cluster(inode->i_sb); | 
 | 		start = ocfs2_align_clusters_to_page_index(inode->i_sb, cpos); | 
 | 		/* | 
 | 		 * We need the index *past* the last page we could possibly | 
 | 		 * touch.  This is the page past the end of the write or | 
 | 		 * i_size, whichever is greater. | 
 | 		 */ | 
 | 		last_byte = max(user_pos + user_len, i_size_read(inode)); | 
 | 		BUG_ON(last_byte < 1); | 
 | 		end_index = ((last_byte - 1) >> PAGE_SHIFT) + 1; | 
 | 		if ((start + wc->w_num_pages) > end_index) | 
 | 			wc->w_num_pages = end_index - start; | 
 | 	} else { | 
 | 		wc->w_num_pages = 1; | 
 | 		start = target_index; | 
 | 	} | 
 | 	end_index = (user_pos + user_len - 1) >> PAGE_SHIFT; | 
 |  | 
 | 	for(i = 0; i < wc->w_num_pages; i++) { | 
 | 		index = start + i; | 
 |  | 
 | 		if (index >= target_index && index <= end_index && | 
 | 		    wc->w_type == OCFS2_WRITE_MMAP) { | 
 | 			/* | 
 | 			 * ocfs2_pagemkwrite() is a little different | 
 | 			 * and wants us to directly use the page | 
 | 			 * passed in. | 
 | 			 */ | 
 | 			lock_page(mmap_page); | 
 |  | 
 | 			/* Exit and let the caller retry */ | 
 | 			if (mmap_page->mapping != mapping) { | 
 | 				WARN_ON(mmap_page->mapping); | 
 | 				unlock_page(mmap_page); | 
 | 				ret = -EAGAIN; | 
 | 				goto out; | 
 | 			} | 
 |  | 
 | 			get_page(mmap_page); | 
 | 			wc->w_pages[i] = mmap_page; | 
 | 			wc->w_target_locked = true; | 
 | 		} else if (index >= target_index && index <= end_index && | 
 | 			   wc->w_type == OCFS2_WRITE_DIRECT) { | 
 | 			/* Direct write has no mapping page. */ | 
 | 			wc->w_pages[i] = NULL; | 
 | 			continue; | 
 | 		} else { | 
 | 			wc->w_pages[i] = find_or_create_page(mapping, index, | 
 | 							     GFP_NOFS); | 
 | 			if (!wc->w_pages[i]) { | 
 | 				ret = -ENOMEM; | 
 | 				mlog_errno(ret); | 
 | 				goto out; | 
 | 			} | 
 | 		} | 
 | 		wait_for_stable_page(wc->w_pages[i]); | 
 |  | 
 | 		if (index == target_index) | 
 | 			wc->w_target_page = wc->w_pages[i]; | 
 | 	} | 
 | out: | 
 | 	if (ret) | 
 | 		wc->w_target_locked = false; | 
 | 	return ret; | 
 | } | 
 |  | 
 | /* | 
 |  * Prepare a single cluster for write one cluster into the file. | 
 |  */ | 
 | static int ocfs2_write_cluster(struct address_space *mapping, | 
 | 			       u32 *phys, unsigned int new, | 
 | 			       unsigned int clear_unwritten, | 
 | 			       unsigned int should_zero, | 
 | 			       struct ocfs2_alloc_context *data_ac, | 
 | 			       struct ocfs2_alloc_context *meta_ac, | 
 | 			       struct ocfs2_write_ctxt *wc, u32 cpos, | 
 | 			       loff_t user_pos, unsigned user_len) | 
 | { | 
 | 	int ret, i; | 
 | 	u64 p_blkno; | 
 | 	struct inode *inode = mapping->host; | 
 | 	struct ocfs2_extent_tree et; | 
 | 	int bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1); | 
 |  | 
 | 	if (new) { | 
 | 		u32 tmp_pos; | 
 |  | 
 | 		/* | 
 | 		 * This is safe to call with the page locks - it won't take | 
 | 		 * any additional semaphores or cluster locks. | 
 | 		 */ | 
 | 		tmp_pos = cpos; | 
 | 		ret = ocfs2_add_inode_data(OCFS2_SB(inode->i_sb), inode, | 
 | 					   &tmp_pos, 1, !clear_unwritten, | 
 | 					   wc->w_di_bh, wc->w_handle, | 
 | 					   data_ac, meta_ac, NULL); | 
 | 		/* | 
 | 		 * This shouldn't happen because we must have already | 
 | 		 * calculated the correct meta data allocation required. The | 
 | 		 * internal tree allocation code should know how to increase | 
 | 		 * transaction credits itself. | 
 | 		 * | 
 | 		 * If need be, we could handle -EAGAIN for a | 
 | 		 * RESTART_TRANS here. | 
 | 		 */ | 
 | 		mlog_bug_on_msg(ret == -EAGAIN, | 
 | 				"Inode %llu: EAGAIN return during allocation.\n", | 
 | 				(unsigned long long)OCFS2_I(inode)->ip_blkno); | 
 | 		if (ret < 0) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 	} else if (clear_unwritten) { | 
 | 		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), | 
 | 					      wc->w_di_bh); | 
 | 		ret = ocfs2_mark_extent_written(inode, &et, | 
 | 						wc->w_handle, cpos, 1, *phys, | 
 | 						meta_ac, &wc->w_dealloc); | 
 | 		if (ret < 0) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * The only reason this should fail is due to an inability to | 
 | 	 * find the extent added. | 
 | 	 */ | 
 | 	ret = ocfs2_get_clusters(inode, cpos, phys, NULL, NULL); | 
 | 	if (ret < 0) { | 
 | 		mlog(ML_ERROR, "Get physical blkno failed for inode %llu, " | 
 | 			    "at logical cluster %u", | 
 | 			    (unsigned long long)OCFS2_I(inode)->ip_blkno, cpos); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	BUG_ON(*phys == 0); | 
 |  | 
 | 	p_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *phys); | 
 | 	if (!should_zero) | 
 | 		p_blkno += (user_pos >> inode->i_sb->s_blocksize_bits) & (u64)(bpc - 1); | 
 |  | 
 | 	for(i = 0; i < wc->w_num_pages; i++) { | 
 | 		int tmpret; | 
 |  | 
 | 		/* This is the direct io target page. */ | 
 | 		if (wc->w_pages[i] == NULL) { | 
 | 			p_blkno++; | 
 | 			continue; | 
 | 		} | 
 |  | 
 | 		tmpret = ocfs2_prepare_page_for_write(inode, &p_blkno, wc, | 
 | 						      wc->w_pages[i], cpos, | 
 | 						      user_pos, user_len, | 
 | 						      should_zero); | 
 | 		if (tmpret) { | 
 | 			mlog_errno(tmpret); | 
 | 			if (ret == 0) | 
 | 				ret = tmpret; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * We only have cleanup to do in case of allocating write. | 
 | 	 */ | 
 | 	if (ret && new) | 
 | 		ocfs2_write_failure(inode, wc, user_pos, user_len); | 
 |  | 
 | out: | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int ocfs2_write_cluster_by_desc(struct address_space *mapping, | 
 | 				       struct ocfs2_alloc_context *data_ac, | 
 | 				       struct ocfs2_alloc_context *meta_ac, | 
 | 				       struct ocfs2_write_ctxt *wc, | 
 | 				       loff_t pos, unsigned len) | 
 | { | 
 | 	int ret, i; | 
 | 	loff_t cluster_off; | 
 | 	unsigned int local_len = len; | 
 | 	struct ocfs2_write_cluster_desc *desc; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(mapping->host->i_sb); | 
 |  | 
 | 	for (i = 0; i < wc->w_clen; i++) { | 
 | 		desc = &wc->w_desc[i]; | 
 |  | 
 | 		/* | 
 | 		 * We have to make sure that the total write passed in | 
 | 		 * doesn't extend past a single cluster. | 
 | 		 */ | 
 | 		local_len = len; | 
 | 		cluster_off = pos & (osb->s_clustersize - 1); | 
 | 		if ((cluster_off + local_len) > osb->s_clustersize) | 
 | 			local_len = osb->s_clustersize - cluster_off; | 
 |  | 
 | 		ret = ocfs2_write_cluster(mapping, &desc->c_phys, | 
 | 					  desc->c_new, | 
 | 					  desc->c_clear_unwritten, | 
 | 					  desc->c_needs_zero, | 
 | 					  data_ac, meta_ac, | 
 | 					  wc, desc->c_cpos, pos, local_len); | 
 | 		if (ret) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 |  | 
 | 		len -= local_len; | 
 | 		pos += local_len; | 
 | 	} | 
 |  | 
 | 	ret = 0; | 
 | out: | 
 | 	return ret; | 
 | } | 
 |  | 
 | /* | 
 |  * ocfs2_write_end() wants to know which parts of the target page it | 
 |  * should complete the write on. It's easiest to compute them ahead of | 
 |  * time when a more complete view of the write is available. | 
 |  */ | 
 | static void ocfs2_set_target_boundaries(struct ocfs2_super *osb, | 
 | 					struct ocfs2_write_ctxt *wc, | 
 | 					loff_t pos, unsigned len, int alloc) | 
 | { | 
 | 	struct ocfs2_write_cluster_desc *desc; | 
 |  | 
 | 	wc->w_target_from = pos & (PAGE_SIZE - 1); | 
 | 	wc->w_target_to = wc->w_target_from + len; | 
 |  | 
 | 	if (alloc == 0) | 
 | 		return; | 
 |  | 
 | 	/* | 
 | 	 * Allocating write - we may have different boundaries based | 
 | 	 * on page size and cluster size. | 
 | 	 * | 
 | 	 * NOTE: We can no longer compute one value from the other as | 
 | 	 * the actual write length and user provided length may be | 
 | 	 * different. | 
 | 	 */ | 
 |  | 
 | 	if (wc->w_large_pages) { | 
 | 		/* | 
 | 		 * We only care about the 1st and last cluster within | 
 | 		 * our range and whether they should be zero'd or not. Either | 
 | 		 * value may be extended out to the start/end of a | 
 | 		 * newly allocated cluster. | 
 | 		 */ | 
 | 		desc = &wc->w_desc[0]; | 
 | 		if (desc->c_needs_zero) | 
 | 			ocfs2_figure_cluster_boundaries(osb, | 
 | 							desc->c_cpos, | 
 | 							&wc->w_target_from, | 
 | 							NULL); | 
 |  | 
 | 		desc = &wc->w_desc[wc->w_clen - 1]; | 
 | 		if (desc->c_needs_zero) | 
 | 			ocfs2_figure_cluster_boundaries(osb, | 
 | 							desc->c_cpos, | 
 | 							NULL, | 
 | 							&wc->w_target_to); | 
 | 	} else { | 
 | 		wc->w_target_from = 0; | 
 | 		wc->w_target_to = PAGE_SIZE; | 
 | 	} | 
 | } | 
 |  | 
 | /* | 
 |  * Check if this extent is marked UNWRITTEN by direct io. If so, we need not to | 
 |  * do the zero work. And should not to clear UNWRITTEN since it will be cleared | 
 |  * by the direct io procedure. | 
 |  * If this is a new extent that allocated by direct io, we should mark it in | 
 |  * the ip_unwritten_list. | 
 |  */ | 
 | static int ocfs2_unwritten_check(struct inode *inode, | 
 | 				 struct ocfs2_write_ctxt *wc, | 
 | 				 struct ocfs2_write_cluster_desc *desc) | 
 | { | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 | 	struct ocfs2_unwritten_extent *ue = NULL, *new = NULL; | 
 | 	int ret = 0; | 
 |  | 
 | 	if (!desc->c_needs_zero) | 
 | 		return 0; | 
 |  | 
 | retry: | 
 | 	spin_lock(&oi->ip_lock); | 
 | 	/* Needs not to zero no metter buffer or direct. The one who is zero | 
 | 	 * the cluster is doing zero. And he will clear unwritten after all | 
 | 	 * cluster io finished. */ | 
 | 	list_for_each_entry(ue, &oi->ip_unwritten_list, ue_ip_node) { | 
 | 		if (desc->c_cpos == ue->ue_cpos) { | 
 | 			BUG_ON(desc->c_new); | 
 | 			desc->c_needs_zero = 0; | 
 | 			desc->c_clear_unwritten = 0; | 
 | 			goto unlock; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (wc->w_type != OCFS2_WRITE_DIRECT) | 
 | 		goto unlock; | 
 |  | 
 | 	if (new == NULL) { | 
 | 		spin_unlock(&oi->ip_lock); | 
 | 		new = kmalloc(sizeof(struct ocfs2_unwritten_extent), | 
 | 			     GFP_NOFS); | 
 | 		if (new == NULL) { | 
 | 			ret = -ENOMEM; | 
 | 			goto out; | 
 | 		} | 
 | 		goto retry; | 
 | 	} | 
 | 	/* This direct write will doing zero. */ | 
 | 	new->ue_cpos = desc->c_cpos; | 
 | 	new->ue_phys = desc->c_phys; | 
 | 	desc->c_clear_unwritten = 0; | 
 | 	list_add_tail(&new->ue_ip_node, &oi->ip_unwritten_list); | 
 | 	list_add_tail(&new->ue_node, &wc->w_unwritten_list); | 
 | 	wc->w_unwritten_count++; | 
 | 	new = NULL; | 
 | unlock: | 
 | 	spin_unlock(&oi->ip_lock); | 
 | out: | 
 | 	if (new) | 
 | 		kfree(new); | 
 | 	return ret; | 
 | } | 
 |  | 
 | /* | 
 |  * Populate each single-cluster write descriptor in the write context | 
 |  * with information about the i/o to be done. | 
 |  * | 
 |  * Returns the number of clusters that will have to be allocated, as | 
 |  * well as a worst case estimate of the number of extent records that | 
 |  * would have to be created during a write to an unwritten region. | 
 |  */ | 
 | static int ocfs2_populate_write_desc(struct inode *inode, | 
 | 				     struct ocfs2_write_ctxt *wc, | 
 | 				     unsigned int *clusters_to_alloc, | 
 | 				     unsigned int *extents_to_split) | 
 | { | 
 | 	int ret; | 
 | 	struct ocfs2_write_cluster_desc *desc; | 
 | 	unsigned int num_clusters = 0; | 
 | 	unsigned int ext_flags = 0; | 
 | 	u32 phys = 0; | 
 | 	int i; | 
 |  | 
 | 	*clusters_to_alloc = 0; | 
 | 	*extents_to_split = 0; | 
 |  | 
 | 	for (i = 0; i < wc->w_clen; i++) { | 
 | 		desc = &wc->w_desc[i]; | 
 | 		desc->c_cpos = wc->w_cpos + i; | 
 |  | 
 | 		if (num_clusters == 0) { | 
 | 			/* | 
 | 			 * Need to look up the next extent record. | 
 | 			 */ | 
 | 			ret = ocfs2_get_clusters(inode, desc->c_cpos, &phys, | 
 | 						 &num_clusters, &ext_flags); | 
 | 			if (ret) { | 
 | 				mlog_errno(ret); | 
 | 				goto out; | 
 | 			} | 
 |  | 
 | 			/* We should already CoW the refcountd extent. */ | 
 | 			BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED); | 
 |  | 
 | 			/* | 
 | 			 * Assume worst case - that we're writing in | 
 | 			 * the middle of the extent. | 
 | 			 * | 
 | 			 * We can assume that the write proceeds from | 
 | 			 * left to right, in which case the extent | 
 | 			 * insert code is smart enough to coalesce the | 
 | 			 * next splits into the previous records created. | 
 | 			 */ | 
 | 			if (ext_flags & OCFS2_EXT_UNWRITTEN) | 
 | 				*extents_to_split = *extents_to_split + 2; | 
 | 		} else if (phys) { | 
 | 			/* | 
 | 			 * Only increment phys if it doesn't describe | 
 | 			 * a hole. | 
 | 			 */ | 
 | 			phys++; | 
 | 		} | 
 |  | 
 | 		/* | 
 | 		 * If w_first_new_cpos is < UINT_MAX, we have a non-sparse | 
 | 		 * file that got extended.  w_first_new_cpos tells us | 
 | 		 * where the newly allocated clusters are so we can | 
 | 		 * zero them. | 
 | 		 */ | 
 | 		if (desc->c_cpos >= wc->w_first_new_cpos) { | 
 | 			BUG_ON(phys == 0); | 
 | 			desc->c_needs_zero = 1; | 
 | 		} | 
 |  | 
 | 		desc->c_phys = phys; | 
 | 		if (phys == 0) { | 
 | 			desc->c_new = 1; | 
 | 			desc->c_needs_zero = 1; | 
 | 			desc->c_clear_unwritten = 1; | 
 | 			*clusters_to_alloc = *clusters_to_alloc + 1; | 
 | 		} | 
 |  | 
 | 		if (ext_flags & OCFS2_EXT_UNWRITTEN) { | 
 | 			desc->c_clear_unwritten = 1; | 
 | 			desc->c_needs_zero = 1; | 
 | 		} | 
 |  | 
 | 		ret = ocfs2_unwritten_check(inode, wc, desc); | 
 | 		if (ret) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 |  | 
 | 		num_clusters--; | 
 | 	} | 
 |  | 
 | 	ret = 0; | 
 | out: | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int ocfs2_write_begin_inline(struct address_space *mapping, | 
 | 				    struct inode *inode, | 
 | 				    struct ocfs2_write_ctxt *wc) | 
 | { | 
 | 	int ret; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 | 	struct page *page; | 
 | 	handle_t *handle; | 
 | 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data; | 
 |  | 
 | 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS); | 
 | 	if (IS_ERR(handle)) { | 
 | 		ret = PTR_ERR(handle); | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	page = find_or_create_page(mapping, 0, GFP_NOFS); | 
 | 	if (!page) { | 
 | 		ocfs2_commit_trans(osb, handle); | 
 | 		ret = -ENOMEM; | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 | 	/* | 
 | 	 * If we don't set w_num_pages then this page won't get unlocked | 
 | 	 * and freed on cleanup of the write context. | 
 | 	 */ | 
 | 	wc->w_pages[0] = wc->w_target_page = page; | 
 | 	wc->w_num_pages = 1; | 
 |  | 
 | 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh, | 
 | 				      OCFS2_JOURNAL_ACCESS_WRITE); | 
 | 	if (ret) { | 
 | 		ocfs2_commit_trans(osb, handle); | 
 |  | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)) | 
 | 		ocfs2_set_inode_data_inline(inode, di); | 
 |  | 
 | 	if (!PageUptodate(page)) { | 
 | 		ret = ocfs2_read_inline_data(inode, page, wc->w_di_bh); | 
 | 		if (ret) { | 
 | 			ocfs2_commit_trans(osb, handle); | 
 |  | 
 | 			goto out; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	wc->w_handle = handle; | 
 | out: | 
 | 	return ret; | 
 | } | 
 |  | 
 | int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size) | 
 | { | 
 | 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; | 
 |  | 
 | 	if (new_size <= le16_to_cpu(di->id2.i_data.id_count)) | 
 | 		return 1; | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int ocfs2_try_to_write_inline_data(struct address_space *mapping, | 
 | 					  struct inode *inode, loff_t pos, | 
 | 					  unsigned len, struct page *mmap_page, | 
 | 					  struct ocfs2_write_ctxt *wc) | 
 | { | 
 | 	int ret, written = 0; | 
 | 	loff_t end = pos + len; | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 | 	struct ocfs2_dinode *di = NULL; | 
 |  | 
 | 	trace_ocfs2_try_to_write_inline_data((unsigned long long)oi->ip_blkno, | 
 | 					     len, (unsigned long long)pos, | 
 | 					     oi->ip_dyn_features); | 
 |  | 
 | 	/* | 
 | 	 * Handle inodes which already have inline data 1st. | 
 | 	 */ | 
 | 	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) { | 
 | 		if (mmap_page == NULL && | 
 | 		    ocfs2_size_fits_inline_data(wc->w_di_bh, end)) | 
 | 			goto do_inline_write; | 
 |  | 
 | 		/* | 
 | 		 * The write won't fit - we have to give this inode an | 
 | 		 * inline extent list now. | 
 | 		 */ | 
 | 		ret = ocfs2_convert_inline_data_to_extents(inode, wc->w_di_bh); | 
 | 		if (ret) | 
 | 			mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * Check whether the inode can accept inline data. | 
 | 	 */ | 
 | 	if (oi->ip_clusters != 0 || i_size_read(inode) != 0) | 
 | 		return 0; | 
 |  | 
 | 	/* | 
 | 	 * Check whether the write can fit. | 
 | 	 */ | 
 | 	di = (struct ocfs2_dinode *)wc->w_di_bh->b_data; | 
 | 	if (mmap_page || | 
 | 	    end > ocfs2_max_inline_data_with_xattr(inode->i_sb, di)) | 
 | 		return 0; | 
 |  | 
 | do_inline_write: | 
 | 	ret = ocfs2_write_begin_inline(mapping, inode, wc); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * This signals to the caller that the data can be written | 
 | 	 * inline. | 
 | 	 */ | 
 | 	written = 1; | 
 | out: | 
 | 	return written ? written : ret; | 
 | } | 
 |  | 
 | /* | 
 |  * This function only does anything for file systems which can't | 
 |  * handle sparse files. | 
 |  * | 
 |  * What we want to do here is fill in any hole between the current end | 
 |  * of allocation and the end of our write. That way the rest of the | 
 |  * write path can treat it as an non-allocating write, which has no | 
 |  * special case code for sparse/nonsparse files. | 
 |  */ | 
 | static int ocfs2_expand_nonsparse_inode(struct inode *inode, | 
 | 					struct buffer_head *di_bh, | 
 | 					loff_t pos, unsigned len, | 
 | 					struct ocfs2_write_ctxt *wc) | 
 | { | 
 | 	int ret; | 
 | 	loff_t newsize = pos + len; | 
 |  | 
 | 	BUG_ON(ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))); | 
 |  | 
 | 	if (newsize <= i_size_read(inode)) | 
 | 		return 0; | 
 |  | 
 | 	ret = ocfs2_extend_no_holes(inode, di_bh, newsize, pos); | 
 | 	if (ret) | 
 | 		mlog_errno(ret); | 
 |  | 
 | 	/* There is no wc if this is call from direct. */ | 
 | 	if (wc) | 
 | 		wc->w_first_new_cpos = | 
 | 			ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode)); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int ocfs2_zero_tail(struct inode *inode, struct buffer_head *di_bh, | 
 | 			   loff_t pos) | 
 | { | 
 | 	int ret = 0; | 
 |  | 
 | 	BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))); | 
 | 	if (pos > i_size_read(inode)) | 
 | 		ret = ocfs2_zero_extend(inode, di_bh, pos); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | int ocfs2_write_begin_nolock(struct address_space *mapping, | 
 | 			     loff_t pos, unsigned len, ocfs2_write_type_t type, | 
 | 			     struct page **pagep, void **fsdata, | 
 | 			     struct buffer_head *di_bh, struct page *mmap_page) | 
 | { | 
 | 	int ret, cluster_of_pages, credits = OCFS2_INODE_UPDATE_CREDITS; | 
 | 	unsigned int clusters_to_alloc, extents_to_split, clusters_need = 0; | 
 | 	struct ocfs2_write_ctxt *wc; | 
 | 	struct inode *inode = mapping->host; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 | 	struct ocfs2_dinode *di; | 
 | 	struct ocfs2_alloc_context *data_ac = NULL; | 
 | 	struct ocfs2_alloc_context *meta_ac = NULL; | 
 | 	handle_t *handle; | 
 | 	struct ocfs2_extent_tree et; | 
 | 	int try_free = 1, ret1; | 
 |  | 
 | try_again: | 
 | 	ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, type, di_bh); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	if (ocfs2_supports_inline_data(osb)) { | 
 | 		ret = ocfs2_try_to_write_inline_data(mapping, inode, pos, len, | 
 | 						     mmap_page, wc); | 
 | 		if (ret == 1) { | 
 | 			ret = 0; | 
 | 			goto success; | 
 | 		} | 
 | 		if (ret < 0) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	/* Direct io change i_size late, should not zero tail here. */ | 
 | 	if (type != OCFS2_WRITE_DIRECT) { | 
 | 		if (ocfs2_sparse_alloc(osb)) | 
 | 			ret = ocfs2_zero_tail(inode, di_bh, pos); | 
 | 		else | 
 | 			ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos, | 
 | 							   len, wc); | 
 | 		if (ret) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_check_range_for_refcount(inode, pos, len); | 
 | 	if (ret < 0) { | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} else if (ret == 1) { | 
 | 		clusters_need = wc->w_clen; | 
 | 		ret = ocfs2_refcount_cow(inode, di_bh, | 
 | 					 wc->w_cpos, wc->w_clen, UINT_MAX); | 
 | 		if (ret) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_populate_write_desc(inode, wc, &clusters_to_alloc, | 
 | 					&extents_to_split); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 | 	clusters_need += clusters_to_alloc; | 
 |  | 
 | 	di = (struct ocfs2_dinode *)wc->w_di_bh->b_data; | 
 |  | 
 | 	trace_ocfs2_write_begin_nolock( | 
 | 			(unsigned long long)OCFS2_I(inode)->ip_blkno, | 
 | 			(long long)i_size_read(inode), | 
 | 			le32_to_cpu(di->i_clusters), | 
 | 			pos, len, type, mmap_page, | 
 | 			clusters_to_alloc, extents_to_split); | 
 |  | 
 | 	/* | 
 | 	 * We set w_target_from, w_target_to here so that | 
 | 	 * ocfs2_write_end() knows which range in the target page to | 
 | 	 * write out. An allocation requires that we write the entire | 
 | 	 * cluster range. | 
 | 	 */ | 
 | 	if (clusters_to_alloc || extents_to_split) { | 
 | 		/* | 
 | 		 * XXX: We are stretching the limits of | 
 | 		 * ocfs2_lock_allocators(). It greatly over-estimates | 
 | 		 * the work to be done. | 
 | 		 */ | 
 | 		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), | 
 | 					      wc->w_di_bh); | 
 | 		ret = ocfs2_lock_allocators(inode, &et, | 
 | 					    clusters_to_alloc, extents_to_split, | 
 | 					    &data_ac, &meta_ac); | 
 | 		if (ret) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 |  | 
 | 		if (data_ac) | 
 | 			data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv; | 
 |  | 
 | 		credits = ocfs2_calc_extend_credits(inode->i_sb, | 
 | 						    &di->id2.i_list); | 
 | 	} else if (type == OCFS2_WRITE_DIRECT) | 
 | 		/* direct write needs not to start trans if no extents alloc. */ | 
 | 		goto success; | 
 |  | 
 | 	/* | 
 | 	 * We have to zero sparse allocated clusters, unwritten extent clusters, | 
 | 	 * and non-sparse clusters we just extended.  For non-sparse writes, | 
 | 	 * we know zeros will only be needed in the first and/or last cluster. | 
 | 	 */ | 
 | 	if (wc->w_clen && (wc->w_desc[0].c_needs_zero || | 
 | 			   wc->w_desc[wc->w_clen - 1].c_needs_zero)) | 
 | 		cluster_of_pages = 1; | 
 | 	else | 
 | 		cluster_of_pages = 0; | 
 |  | 
 | 	ocfs2_set_target_boundaries(osb, wc, pos, len, cluster_of_pages); | 
 |  | 
 | 	handle = ocfs2_start_trans(osb, credits); | 
 | 	if (IS_ERR(handle)) { | 
 | 		ret = PTR_ERR(handle); | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	wc->w_handle = handle; | 
 |  | 
 | 	if (clusters_to_alloc) { | 
 | 		ret = dquot_alloc_space_nodirty(inode, | 
 | 			ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc)); | 
 | 		if (ret) | 
 | 			goto out_commit; | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh, | 
 | 				      OCFS2_JOURNAL_ACCESS_WRITE); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto out_quota; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * Fill our page array first. That way we've grabbed enough so | 
 | 	 * that we can zero and flush if we error after adding the | 
 | 	 * extent. | 
 | 	 */ | 
 | 	ret = ocfs2_grab_pages_for_write(mapping, wc, wc->w_cpos, pos, len, | 
 | 					 cluster_of_pages, mmap_page); | 
 | 	if (ret && ret != -EAGAIN) { | 
 | 		mlog_errno(ret); | 
 | 		goto out_quota; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * ocfs2_grab_pages_for_write() returns -EAGAIN if it could not lock | 
 | 	 * the target page. In this case, we exit with no error and no target | 
 | 	 * page. This will trigger the caller, page_mkwrite(), to re-try | 
 | 	 * the operation. | 
 | 	 */ | 
 | 	if (ret == -EAGAIN) { | 
 | 		BUG_ON(wc->w_target_page); | 
 | 		ret = 0; | 
 | 		goto out_quota; | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_write_cluster_by_desc(mapping, data_ac, meta_ac, wc, pos, | 
 | 					  len); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto out_quota; | 
 | 	} | 
 |  | 
 | 	if (data_ac) | 
 | 		ocfs2_free_alloc_context(data_ac); | 
 | 	if (meta_ac) | 
 | 		ocfs2_free_alloc_context(meta_ac); | 
 |  | 
 | success: | 
 | 	if (pagep) | 
 | 		*pagep = wc->w_target_page; | 
 | 	*fsdata = wc; | 
 | 	return 0; | 
 | out_quota: | 
 | 	if (clusters_to_alloc) | 
 | 		dquot_free_space(inode, | 
 | 			  ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc)); | 
 | out_commit: | 
 | 	ocfs2_commit_trans(osb, handle); | 
 |  | 
 | out: | 
 | 	/* | 
 | 	 * The mmapped page won't be unlocked in ocfs2_free_write_ctxt(), | 
 | 	 * even in case of error here like ENOSPC and ENOMEM. So, we need | 
 | 	 * to unlock the target page manually to prevent deadlocks when | 
 | 	 * retrying again on ENOSPC, or when returning non-VM_FAULT_LOCKED | 
 | 	 * to VM code. | 
 | 	 */ | 
 | 	if (wc->w_target_locked) | 
 | 		unlock_page(mmap_page); | 
 |  | 
 | 	ocfs2_free_write_ctxt(inode, wc); | 
 |  | 
 | 	if (data_ac) { | 
 | 		ocfs2_free_alloc_context(data_ac); | 
 | 		data_ac = NULL; | 
 | 	} | 
 | 	if (meta_ac) { | 
 | 		ocfs2_free_alloc_context(meta_ac); | 
 | 		meta_ac = NULL; | 
 | 	} | 
 |  | 
 | 	if (ret == -ENOSPC && try_free) { | 
 | 		/* | 
 | 		 * Try to free some truncate log so that we can have enough | 
 | 		 * clusters to allocate. | 
 | 		 */ | 
 | 		try_free = 0; | 
 |  | 
 | 		ret1 = ocfs2_try_to_free_truncate_log(osb, clusters_need); | 
 | 		if (ret1 == 1) | 
 | 			goto try_again; | 
 |  | 
 | 		if (ret1 < 0) | 
 | 			mlog_errno(ret1); | 
 | 	} | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int ocfs2_write_begin(struct file *file, struct address_space *mapping, | 
 | 			     loff_t pos, unsigned len, unsigned flags, | 
 | 			     struct page **pagep, void **fsdata) | 
 | { | 
 | 	int ret; | 
 | 	struct buffer_head *di_bh = NULL; | 
 | 	struct inode *inode = mapping->host; | 
 |  | 
 | 	ret = ocfs2_inode_lock(inode, &di_bh, 1); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * Take alloc sem here to prevent concurrent lookups. That way | 
 | 	 * the mapping, zeroing and tree manipulation within | 
 | 	 * ocfs2_write() will be safe against ->readpage(). This | 
 | 	 * should also serve to lock out allocation from a shared | 
 | 	 * writeable region. | 
 | 	 */ | 
 | 	down_write(&OCFS2_I(inode)->ip_alloc_sem); | 
 |  | 
 | 	ret = ocfs2_write_begin_nolock(mapping, pos, len, OCFS2_WRITE_BUFFER, | 
 | 				       pagep, fsdata, di_bh, NULL); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto out_fail; | 
 | 	} | 
 |  | 
 | 	brelse(di_bh); | 
 |  | 
 | 	return 0; | 
 |  | 
 | out_fail: | 
 | 	up_write(&OCFS2_I(inode)->ip_alloc_sem); | 
 |  | 
 | 	brelse(di_bh); | 
 | 	ocfs2_inode_unlock(inode, 1); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static void ocfs2_write_end_inline(struct inode *inode, loff_t pos, | 
 | 				   unsigned len, unsigned *copied, | 
 | 				   struct ocfs2_dinode *di, | 
 | 				   struct ocfs2_write_ctxt *wc) | 
 | { | 
 | 	void *kaddr; | 
 |  | 
 | 	if (unlikely(*copied < len)) { | 
 | 		if (!PageUptodate(wc->w_target_page)) { | 
 | 			*copied = 0; | 
 | 			return; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	kaddr = kmap_atomic(wc->w_target_page); | 
 | 	memcpy(di->id2.i_data.id_data + pos, kaddr + pos, *copied); | 
 | 	kunmap_atomic(kaddr); | 
 |  | 
 | 	trace_ocfs2_write_end_inline( | 
 | 	     (unsigned long long)OCFS2_I(inode)->ip_blkno, | 
 | 	     (unsigned long long)pos, *copied, | 
 | 	     le16_to_cpu(di->id2.i_data.id_count), | 
 | 	     le16_to_cpu(di->i_dyn_features)); | 
 | } | 
 |  | 
 | int ocfs2_write_end_nolock(struct address_space *mapping, | 
 | 			   loff_t pos, unsigned len, unsigned copied, void *fsdata) | 
 | { | 
 | 	int i, ret; | 
 | 	unsigned from, to, start = pos & (PAGE_SIZE - 1); | 
 | 	struct inode *inode = mapping->host; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 | 	struct ocfs2_write_ctxt *wc = fsdata; | 
 | 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data; | 
 | 	handle_t *handle = wc->w_handle; | 
 | 	struct page *tmppage; | 
 |  | 
 | 	BUG_ON(!list_empty(&wc->w_unwritten_list)); | 
 |  | 
 | 	if (handle) { | 
 | 		ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), | 
 | 				wc->w_di_bh, OCFS2_JOURNAL_ACCESS_WRITE); | 
 | 		if (ret) { | 
 | 			copied = ret; | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) { | 
 | 		ocfs2_write_end_inline(inode, pos, len, &copied, di, wc); | 
 | 		goto out_write_size; | 
 | 	} | 
 |  | 
 | 	if (unlikely(copied < len) && wc->w_target_page) { | 
 | 		if (!PageUptodate(wc->w_target_page)) | 
 | 			copied = 0; | 
 |  | 
 | 		ocfs2_zero_new_buffers(wc->w_target_page, start+copied, | 
 | 				       start+len); | 
 | 	} | 
 | 	if (wc->w_target_page) | 
 | 		flush_dcache_page(wc->w_target_page); | 
 |  | 
 | 	for(i = 0; i < wc->w_num_pages; i++) { | 
 | 		tmppage = wc->w_pages[i]; | 
 |  | 
 | 		/* This is the direct io target page. */ | 
 | 		if (tmppage == NULL) | 
 | 			continue; | 
 |  | 
 | 		if (tmppage == wc->w_target_page) { | 
 | 			from = wc->w_target_from; | 
 | 			to = wc->w_target_to; | 
 |  | 
 | 			BUG_ON(from > PAGE_SIZE || | 
 | 			       to > PAGE_SIZE || | 
 | 			       to < from); | 
 | 		} else { | 
 | 			/* | 
 | 			 * Pages adjacent to the target (if any) imply | 
 | 			 * a hole-filling write in which case we want | 
 | 			 * to flush their entire range. | 
 | 			 */ | 
 | 			from = 0; | 
 | 			to = PAGE_SIZE; | 
 | 		} | 
 |  | 
 | 		if (page_has_buffers(tmppage)) { | 
 | 			if (handle && ocfs2_should_order_data(inode)) | 
 | 				ocfs2_jbd2_file_inode(handle, inode); | 
 | 			block_commit_write(tmppage, from, to); | 
 | 		} | 
 | 	} | 
 |  | 
 | out_write_size: | 
 | 	/* Direct io do not update i_size here. */ | 
 | 	if (wc->w_type != OCFS2_WRITE_DIRECT) { | 
 | 		pos += copied; | 
 | 		if (pos > i_size_read(inode)) { | 
 | 			i_size_write(inode, pos); | 
 | 			mark_inode_dirty(inode); | 
 | 		} | 
 | 		inode->i_blocks = ocfs2_inode_sector_count(inode); | 
 | 		di->i_size = cpu_to_le64((u64)i_size_read(inode)); | 
 | 		inode->i_mtime = inode->i_ctime = current_time(inode); | 
 | 		di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec); | 
 | 		di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec); | 
 | 		if (handle) | 
 | 			ocfs2_update_inode_fsync_trans(handle, inode, 1); | 
 | 	} | 
 | 	if (handle) | 
 | 		ocfs2_journal_dirty(handle, wc->w_di_bh); | 
 |  | 
 | out: | 
 | 	/* unlock pages before dealloc since it needs acquiring j_trans_barrier | 
 | 	 * lock, or it will cause a deadlock since journal commit threads holds | 
 | 	 * this lock and will ask for the page lock when flushing the data. | 
 | 	 * put it here to preserve the unlock order. | 
 | 	 */ | 
 | 	ocfs2_unlock_pages(wc); | 
 |  | 
 | 	if (handle) | 
 | 		ocfs2_commit_trans(osb, handle); | 
 |  | 
 | 	ocfs2_run_deallocs(osb, &wc->w_dealloc); | 
 |  | 
 | 	brelse(wc->w_di_bh); | 
 | 	kfree(wc); | 
 |  | 
 | 	return copied; | 
 | } | 
 |  | 
 | static int ocfs2_write_end(struct file *file, struct address_space *mapping, | 
 | 			   loff_t pos, unsigned len, unsigned copied, | 
 | 			   struct page *page, void *fsdata) | 
 | { | 
 | 	int ret; | 
 | 	struct inode *inode = mapping->host; | 
 |  | 
 | 	ret = ocfs2_write_end_nolock(mapping, pos, len, copied, fsdata); | 
 |  | 
 | 	up_write(&OCFS2_I(inode)->ip_alloc_sem); | 
 | 	ocfs2_inode_unlock(inode, 1); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | struct ocfs2_dio_write_ctxt { | 
 | 	struct list_head	dw_zero_list; | 
 | 	unsigned		dw_zero_count; | 
 | 	int			dw_orphaned; | 
 | 	pid_t			dw_writer_pid; | 
 | }; | 
 |  | 
 | static struct ocfs2_dio_write_ctxt * | 
 | ocfs2_dio_alloc_write_ctx(struct buffer_head *bh, int *alloc) | 
 | { | 
 | 	struct ocfs2_dio_write_ctxt *dwc = NULL; | 
 |  | 
 | 	if (bh->b_private) | 
 | 		return bh->b_private; | 
 |  | 
 | 	dwc = kmalloc(sizeof(struct ocfs2_dio_write_ctxt), GFP_NOFS); | 
 | 	if (dwc == NULL) | 
 | 		return NULL; | 
 | 	INIT_LIST_HEAD(&dwc->dw_zero_list); | 
 | 	dwc->dw_zero_count = 0; | 
 | 	dwc->dw_orphaned = 0; | 
 | 	dwc->dw_writer_pid = task_pid_nr(current); | 
 | 	bh->b_private = dwc; | 
 | 	*alloc = 1; | 
 |  | 
 | 	return dwc; | 
 | } | 
 |  | 
 | static void ocfs2_dio_free_write_ctx(struct inode *inode, | 
 | 				     struct ocfs2_dio_write_ctxt *dwc) | 
 | { | 
 | 	ocfs2_free_unwritten_list(inode, &dwc->dw_zero_list); | 
 | 	kfree(dwc); | 
 | } | 
 |  | 
 | /* | 
 |  * TODO: Make this into a generic get_blocks function. | 
 |  * | 
 |  * From do_direct_io in direct-io.c: | 
 |  *  "So what we do is to permit the ->get_blocks function to populate | 
 |  *   bh.b_size with the size of IO which is permitted at this offset and | 
 |  *   this i_blkbits." | 
 |  * | 
 |  * This function is called directly from get_more_blocks in direct-io.c. | 
 |  * | 
 |  * called like this: dio->get_blocks(dio->inode, fs_startblk, | 
 |  * 					fs_count, map_bh, dio->rw == WRITE); | 
 |  */ | 
 | static int ocfs2_dio_wr_get_block(struct inode *inode, sector_t iblock, | 
 | 			       struct buffer_head *bh_result, int create) | 
 | { | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 | 	struct ocfs2_write_ctxt *wc; | 
 | 	struct ocfs2_write_cluster_desc *desc = NULL; | 
 | 	struct ocfs2_dio_write_ctxt *dwc = NULL; | 
 | 	struct buffer_head *di_bh = NULL; | 
 | 	u64 p_blkno; | 
 | 	unsigned int i_blkbits = inode->i_sb->s_blocksize_bits; | 
 | 	loff_t pos = iblock << i_blkbits; | 
 | 	sector_t endblk = (i_size_read(inode) - 1) >> i_blkbits; | 
 | 	unsigned len, total_len = bh_result->b_size; | 
 | 	int ret = 0, first_get_block = 0; | 
 |  | 
 | 	len = osb->s_clustersize - (pos & (osb->s_clustersize - 1)); | 
 | 	len = min(total_len, len); | 
 |  | 
 | 	/* | 
 | 	 * bh_result->b_size is count in get_more_blocks according to write | 
 | 	 * "pos" and "end", we need map twice to return different buffer state: | 
 | 	 * 1. area in file size, not set NEW; | 
 | 	 * 2. area out file size, set  NEW. | 
 | 	 * | 
 | 	 *		   iblock    endblk | 
 | 	 * |--------|---------|---------|--------- | 
 | 	 * |<-------area in file------->| | 
 | 	 */ | 
 |  | 
 | 	if ((iblock <= endblk) && | 
 | 	    ((iblock + ((len - 1) >> i_blkbits)) > endblk)) | 
 | 		len = (endblk - iblock + 1) << i_blkbits; | 
 |  | 
 | 	mlog(0, "get block of %lu at %llu:%u req %u\n", | 
 | 			inode->i_ino, pos, len, total_len); | 
 |  | 
 | 	/* | 
 | 	 * Because we need to change file size in ocfs2_dio_end_io_write(), or | 
 | 	 * we may need to add it to orphan dir. So can not fall to fast path | 
 | 	 * while file size will be changed. | 
 | 	 */ | 
 | 	if (pos + total_len <= i_size_read(inode)) { | 
 |  | 
 | 		/* This is the fast path for re-write. */ | 
 | 		ret = ocfs2_lock_get_block(inode, iblock, bh_result, create); | 
 | 		if (buffer_mapped(bh_result) && | 
 | 		    !buffer_new(bh_result) && | 
 | 		    ret == 0) | 
 | 			goto out; | 
 |  | 
 | 		/* Clear state set by ocfs2_get_block. */ | 
 | 		bh_result->b_state = 0; | 
 | 	} | 
 |  | 
 | 	dwc = ocfs2_dio_alloc_write_ctx(bh_result, &first_get_block); | 
 | 	if (unlikely(dwc == NULL)) { | 
 | 		ret = -ENOMEM; | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	if (ocfs2_clusters_for_bytes(inode->i_sb, pos + total_len) > | 
 | 	    ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode)) && | 
 | 	    !dwc->dw_orphaned) { | 
 | 		/* | 
 | 		 * when we are going to alloc extents beyond file size, add the | 
 | 		 * inode to orphan dir, so we can recall those spaces when | 
 | 		 * system crashed during write. | 
 | 		 */ | 
 | 		ret = ocfs2_add_inode_to_orphan(osb, inode); | 
 | 		if (ret < 0) { | 
 | 			mlog_errno(ret); | 
 | 			goto out; | 
 | 		} | 
 | 		dwc->dw_orphaned = 1; | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_inode_lock(inode, &di_bh, 1); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	down_write(&oi->ip_alloc_sem); | 
 |  | 
 | 	if (first_get_block) { | 
 | 		if (ocfs2_sparse_alloc(osb)) | 
 | 			ret = ocfs2_zero_tail(inode, di_bh, pos); | 
 | 		else | 
 | 			ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos, | 
 | 							   total_len, NULL); | 
 | 		if (ret < 0) { | 
 | 			mlog_errno(ret); | 
 | 			goto unlock; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_write_begin_nolock(inode->i_mapping, pos, len, | 
 | 				       OCFS2_WRITE_DIRECT, NULL, | 
 | 				       (void **)&wc, di_bh, NULL); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto unlock; | 
 | 	} | 
 |  | 
 | 	desc = &wc->w_desc[0]; | 
 |  | 
 | 	p_blkno = ocfs2_clusters_to_blocks(inode->i_sb, desc->c_phys); | 
 | 	BUG_ON(p_blkno == 0); | 
 | 	p_blkno += iblock & (u64)(ocfs2_clusters_to_blocks(inode->i_sb, 1) - 1); | 
 |  | 
 | 	map_bh(bh_result, inode->i_sb, p_blkno); | 
 | 	bh_result->b_size = len; | 
 | 	if (desc->c_needs_zero) | 
 | 		set_buffer_new(bh_result); | 
 |  | 
 | 	if (iblock > endblk) | 
 | 		set_buffer_new(bh_result); | 
 |  | 
 | 	/* May sleep in end_io. It should not happen in a irq context. So defer | 
 | 	 * it to dio work queue. */ | 
 | 	set_buffer_defer_completion(bh_result); | 
 |  | 
 | 	if (!list_empty(&wc->w_unwritten_list)) { | 
 | 		struct ocfs2_unwritten_extent *ue = NULL; | 
 |  | 
 | 		ue = list_first_entry(&wc->w_unwritten_list, | 
 | 				      struct ocfs2_unwritten_extent, | 
 | 				      ue_node); | 
 | 		BUG_ON(ue->ue_cpos != desc->c_cpos); | 
 | 		/* The physical address may be 0, fill it. */ | 
 | 		ue->ue_phys = desc->c_phys; | 
 |  | 
 | 		list_splice_tail_init(&wc->w_unwritten_list, &dwc->dw_zero_list); | 
 | 		dwc->dw_zero_count += wc->w_unwritten_count; | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_write_end_nolock(inode->i_mapping, pos, len, len, wc); | 
 | 	BUG_ON(ret != len); | 
 | 	ret = 0; | 
 | unlock: | 
 | 	up_write(&oi->ip_alloc_sem); | 
 | 	ocfs2_inode_unlock(inode, 1); | 
 | 	brelse(di_bh); | 
 | out: | 
 | 	if (ret < 0) | 
 | 		ret = -EIO; | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int ocfs2_dio_end_io_write(struct inode *inode, | 
 | 				  struct ocfs2_dio_write_ctxt *dwc, | 
 | 				  loff_t offset, | 
 | 				  ssize_t bytes) | 
 | { | 
 | 	struct ocfs2_cached_dealloc_ctxt dealloc; | 
 | 	struct ocfs2_extent_tree et; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 | 	struct ocfs2_inode_info *oi = OCFS2_I(inode); | 
 | 	struct ocfs2_unwritten_extent *ue = NULL; | 
 | 	struct buffer_head *di_bh = NULL; | 
 | 	struct ocfs2_dinode *di; | 
 | 	struct ocfs2_alloc_context *data_ac = NULL; | 
 | 	struct ocfs2_alloc_context *meta_ac = NULL; | 
 | 	handle_t *handle = NULL; | 
 | 	loff_t end = offset + bytes; | 
 | 	int ret = 0, credits = 0, locked = 0; | 
 |  | 
 | 	ocfs2_init_dealloc_ctxt(&dealloc); | 
 |  | 
 | 	/* We do clear unwritten, delete orphan, change i_size here. If neither | 
 | 	 * of these happen, we can skip all this. */ | 
 | 	if (list_empty(&dwc->dw_zero_list) && | 
 | 	    end <= i_size_read(inode) && | 
 | 	    !dwc->dw_orphaned) | 
 | 		goto out; | 
 |  | 
 | 	/* ocfs2_file_write_iter will get i_mutex, so we need not lock if we | 
 | 	 * are in that context. */ | 
 | 	if (dwc->dw_writer_pid != task_pid_nr(current)) { | 
 | 		inode_lock(inode); | 
 | 		locked = 1; | 
 | 	} | 
 |  | 
 | 	ret = ocfs2_inode_lock(inode, &di_bh, 1); | 
 | 	if (ret < 0) { | 
 | 		mlog_errno(ret); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	down_write(&oi->ip_alloc_sem); | 
 |  | 
 | 	/* Delete orphan before acquire i_mutex. */ | 
 | 	if (dwc->dw_orphaned) { | 
 | 		BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); | 
 |  | 
 | 		end = end > i_size_read(inode) ? end : 0; | 
 |  | 
 | 		ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, | 
 | 				!!end, end); | 
 | 		if (ret < 0) | 
 | 			mlog_errno(ret); | 
 | 	} | 
 |  | 
 | 	di = (struct ocfs2_dinode *)di_bh->b_data; | 
 |  | 
 | 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh); | 
 |  | 
 | 	/* Attach dealloc with extent tree in case that we may reuse extents | 
 | 	 * which are already unlinked from current extent tree due to extent | 
 | 	 * rotation and merging. | 
 | 	 */ | 
 | 	et.et_dealloc = &dealloc; | 
 |  | 
 | 	ret = ocfs2_lock_allocators(inode, &et, 0, dwc->dw_zero_count*2, | 
 | 				    &data_ac, &meta_ac); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto unlock; | 
 | 	} | 
 |  | 
 | 	credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); | 
 |  | 
 | 	handle = ocfs2_start_trans(osb, credits); | 
 | 	if (IS_ERR(handle)) { | 
 | 		ret = PTR_ERR(handle); | 
 | 		mlog_errno(ret); | 
 | 		goto unlock; | 
 | 	} | 
 | 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, | 
 | 				      OCFS2_JOURNAL_ACCESS_WRITE); | 
 | 	if (ret) { | 
 | 		mlog_errno(ret); | 
 | 		goto commit; | 
 | 	} | 
 |  | 
 | 	list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { | 
 | 		ret = ocfs2_mark_extent_written(inode, &et, handle, | 
 | 						ue->ue_cpos, 1, | 
 | 						ue->ue_phys, | 
 | 						meta_ac, &dealloc); | 
 | 		if (ret < 0) { | 
 | 			mlog_errno(ret); | 
 | 			break; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (end > i_size_read(inode)) { | 
 | 		ret = ocfs2_set_inode_size(handle, inode, di_bh, end); | 
 | 		if (ret < 0) | 
 | 			mlog_errno(ret); | 
 | 	} | 
 | commit: | 
 | 	ocfs2_commit_trans(osb, handle); | 
 | unlock: | 
 | 	up_write(&oi->ip_alloc_sem); | 
 | 	ocfs2_inode_unlock(inode, 1); | 
 | 	brelse(di_bh); | 
 | out: | 
 | 	if (data_ac) | 
 | 		ocfs2_free_alloc_context(data_ac); | 
 | 	if (meta_ac) | 
 | 		ocfs2_free_alloc_context(meta_ac); | 
 | 	ocfs2_run_deallocs(osb, &dealloc); | 
 | 	if (locked) | 
 | 		inode_unlock(inode); | 
 | 	ocfs2_dio_free_write_ctx(inode, dwc); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | /* | 
 |  * ocfs2_dio_end_io is called by the dio core when a dio is finished.  We're | 
 |  * particularly interested in the aio/dio case.  We use the rw_lock DLM lock | 
 |  * to protect io on one node from truncation on another. | 
 |  */ | 
 | static int ocfs2_dio_end_io(struct kiocb *iocb, | 
 | 			    loff_t offset, | 
 | 			    ssize_t bytes, | 
 | 			    void *private) | 
 | { | 
 | 	struct inode *inode = file_inode(iocb->ki_filp); | 
 | 	int level; | 
 | 	int ret = 0; | 
 |  | 
 | 	/* this io's submitter should not have unlocked this before we could */ | 
 | 	BUG_ON(!ocfs2_iocb_is_rw_locked(iocb)); | 
 |  | 
 | 	if (bytes <= 0) | 
 | 		mlog_ratelimited(ML_ERROR, "Direct IO failed, bytes = %lld", | 
 | 				 (long long)bytes); | 
 | 	if (private) { | 
 | 		if (bytes > 0) | 
 | 			ret = ocfs2_dio_end_io_write(inode, private, offset, | 
 | 						     bytes); | 
 | 		else | 
 | 			ocfs2_dio_free_write_ctx(inode, private); | 
 | 	} | 
 |  | 
 | 	ocfs2_iocb_clear_rw_locked(iocb); | 
 |  | 
 | 	level = ocfs2_iocb_rw_locked_level(iocb); | 
 | 	ocfs2_rw_unlock(inode, level); | 
 | 	return ret; | 
 | } | 
 |  | 
 | static ssize_t ocfs2_direct_IO(struct kiocb *iocb, struct iov_iter *iter) | 
 | { | 
 | 	struct file *file = iocb->ki_filp; | 
 | 	struct inode *inode = file->f_mapping->host; | 
 | 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); | 
 | 	get_block_t *get_block; | 
 |  | 
 | 	/* | 
 | 	 * Fallback to buffered I/O if we see an inode without | 
 | 	 * extents. | 
 | 	 */ | 
 | 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) | 
 | 		return 0; | 
 |  | 
 | 	/* Fallback to buffered I/O if we do not support append dio. */ | 
 | 	if (iocb->ki_pos + iter->count > i_size_read(inode) && | 
 | 	    !ocfs2_supports_append_dio(osb)) | 
 | 		return 0; | 
 |  | 
 | 	if (iov_iter_rw(iter) == READ) | 
 | 		get_block = ocfs2_lock_get_block; | 
 | 	else | 
 | 		get_block = ocfs2_dio_wr_get_block; | 
 |  | 
 | 	return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, | 
 | 				    iter, get_block, | 
 | 				    ocfs2_dio_end_io, NULL, 0); | 
 | } | 
 |  | 
 | const struct address_space_operations ocfs2_aops = { | 
 | 	.readpage		= ocfs2_readpage, | 
 | 	.readpages		= ocfs2_readpages, | 
 | 	.writepage		= ocfs2_writepage, | 
 | 	.write_begin		= ocfs2_write_begin, | 
 | 	.write_end		= ocfs2_write_end, | 
 | 	.bmap			= ocfs2_bmap, | 
 | 	.direct_IO		= ocfs2_direct_IO, | 
 | 	.invalidatepage		= block_invalidatepage, | 
 | 	.releasepage		= ocfs2_releasepage, | 
 | 	.migratepage		= buffer_migrate_page, | 
 | 	.is_partially_uptodate	= block_is_partially_uptodate, | 
 | 	.error_remove_page	= generic_error_remove_page, | 
 | }; |