From: Ross Zwisler Subject: [PATCH v2 4/4] ext4: Add xip hole punching Date: Thu, 5 Dec 2013 13:02:48 -0700 Message-ID: <1386273769-12828-5-git-send-email-ross.zwisler@linux.intel.com> References: <1386273769-12828-1-git-send-email-ross.zwisler@linux.intel.com> Cc: Ross Zwisler To: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, carsteno@de.ibm.com, matthew.r.wilcox@intel.com, andreas.dilger@intel.com Return-path: In-Reply-To: <1386273769-12828-1-git-send-email-ross.zwisler@linux.intel.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org From: Matthew Wilcox We mustn't call ext4_block_zero_page_range() as that will attempt to bring a page into the page cache in order to zero it. To fix this, I made ext4_block_zero_page_range() a wrapper around __ext4_block_zero_page_range(), that will call the new xip_zero_page_range() for XIP files. I also made ext4_block_zero_page_range() static as it is not called outside inode.c. Signed-off-by: Matthew Wilcox [ported to 3.13-rc2] Signed-off-by: Ross Zwisler --- fs/ext4/ext4.h | 2 -- fs/ext4/inode.c | 64 ++++++++++++++++++++++++++++--------------------------- 2 files changed, 33 insertions(+), 33 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 9b509a0..d083ad9 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2122,8 +2122,6 @@ extern int ext4_writepage_trans_blocks(struct inode *); extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks); extern int ext4_block_truncate_page(handle_t *handle, struct address_space *mapping, loff_t from); -extern int ext4_block_zero_page_range(handle_t *handle, - struct address_space *mapping, loff_t from, loff_t length); extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode, loff_t lstart, loff_t lend); extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 18d027f..7b50832 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3349,33 +3349,13 @@ void ext4_set_aops(struct inode *inode) } /* - * ext4_block_truncate_page() zeroes out a mapping from file offset `from' - * up to the end of the block which corresponds to `from'. - * This required during truncate. We need to physically zero the tail end - * of that block so it doesn't yield old data if the file is later grown. - */ -int ext4_block_truncate_page(handle_t *handle, - struct address_space *mapping, loff_t from) -{ - unsigned offset = from & (PAGE_CACHE_SIZE-1); - unsigned length; - unsigned blocksize; - struct inode *inode = mapping->host; - - blocksize = inode->i_sb->s_blocksize; - length = blocksize - (offset & (blocksize - 1)); - - return ext4_block_zero_page_range(handle, mapping, from, length); -} - -/* - * ext4_block_zero_page_range() zeros out a mapping of length 'length' + * __ext4_block_zero_page_range() zeros out a mapping of length 'length' * starting from file offset 'from'. The range to be zero'd must * be contained with in one block. If the specified range exceeds * the end of the block it will be shortened to end of the block * that cooresponds to 'from' */ -int ext4_block_zero_page_range(handle_t *handle, +static int __ext4_block_zero_page_range(handle_t *handle, struct address_space *mapping, loff_t from, loff_t length) { ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT; @@ -3465,6 +3445,34 @@ unlock: return err; } +static int ext4_block_zero_page_range(handle_t *handle, + struct address_space *mapping, loff_t from, loff_t length) +{ + if (mapping_is_xip(mapping)) + return xip_zero_page_range(mapping, from, length); + return __ext4_block_zero_page_range(handle, mapping, from, length); +} + +/* + * ext4_block_truncate_page() zeroes out a mapping from file offset `from' + * up to the end of the block which corresponds to `from'. + * This required during truncate. We need to physically zero the tail end + * of that block so it doesn't yield old data if the file is later grown. + */ +int ext4_block_truncate_page(handle_t *handle, + struct address_space *mapping, loff_t from) +{ + unsigned offset = from & (PAGE_CACHE_SIZE-1); + unsigned length; + unsigned blocksize; + struct inode *inode = mapping->host; + + blocksize = inode->i_sb->s_blocksize; + length = blocksize - (offset & (blocksize - 1)); + + return ext4_block_zero_page_range(handle, mapping, from, length); +} + int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode, loff_t lstart, loff_t length) { @@ -3763,14 +3771,8 @@ void ext4_truncate(struct inode *inode) return; } - if (inode->i_size & (inode->i_sb->s_blocksize - 1)) { - if (mapping_is_xip(inode->i_mapping)) { - if (xip_truncate_page(inode->i_mapping, inode->i_size)) - goto out_stop; - } else - ext4_block_truncate_page(handle, mapping, - inode->i_size); - } + if (inode->i_size & (inode->i_sb->s_blocksize - 1)) + ext4_block_truncate_page(handle, mapping, inode->i_size); /* * We add the inode to the orphan list, so that if this @@ -4687,7 +4689,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr) * Truncate pagecache after we've waited for commit * in data=journal mode to make pages freeable. */ - truncate_pagecache(inode, inode->i_size); + truncate_pagecache(inode, inode->i_size); } /* * We want to call ext4_truncate() even if attr->ia_size == -- 1.7.10.4