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Date: Fri, 18 Nov 2011 18:43:01 +0800
From: Robin Dong <hao.bigrat@...il.com>
To: linux-ext4@...r.kernel.org
Cc: Robin Dong <sanbai@...bao.com>
Subject: [PATCH 6/9 v2 bigalloc] ext4: zero out extra page when users truncate a file
From: Robin Dong <sanbai@...bao.com>
When truncate file to be larger, we need to zero out the pages which beyond
the old i_size.
Signed-off-by: Robin Dong <sanbai@...bao.com>
---
fs/ext4/ext4.h | 4 +-
fs/ext4/extents.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++-
fs/ext4/inode.c | 13 ++++----
fs/ext4/ioctl.c | 2 +-
fs/ext4/super.c | 2 +-
fs/ext4/truncate.h | 2 +-
6 files changed, 89 insertions(+), 12 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 90ae8a2..7d226af 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1886,7 +1886,7 @@ extern void ext4_dirty_inode(struct inode *, int);
extern int ext4_change_inode_journal_flag(struct inode *, int);
extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
extern int ext4_can_truncate(struct inode *inode);
-extern void ext4_truncate(struct inode *);
+extern void ext4_truncate(struct inode *, loff_t oldsize);
extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length);
extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
extern void ext4_set_inode_flags(struct inode *);
@@ -2267,7 +2267,7 @@ extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
int chunk);
extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
struct ext4_map_blocks *map, int flags);
-extern void ext4_ext_truncate(struct inode *);
+extern void ext4_ext_truncate(struct inode *, loff_t oldsize);
extern int ext4_ext_punch_hole(struct file *file, loff_t offset,
loff_t length);
extern void ext4_ext_init(struct super_block *);
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index ccf12a0..7799973 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4131,10 +4131,76 @@ out2:
return err ? err : result;
}
-void ext4_ext_truncate(struct inode *inode)
+int ext4_ext_truncate_zero_pages(handle_t *handle, struct inode *inode,
+ loff_t old_size)
+{
+ struct super_block *sb = inode->i_sb;
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ struct ext4_write_cluster_ctxt *ewcc = NULL;
+ struct page *page;
+ ext4_lblk_t last_block = ((old_size + sb->s_blocksize - 1)
+ >> EXT4_BLOCK_SIZE_BITS(sb)) - 1;
+ ext4_lblk_t left_offset = last_block & (sbi->s_cluster_ratio - 1);
+ ext4_lblk_t right_offset = sbi->s_cluster_ratio - left_offset - 1;
+ ext4_lblk_t begin, index;
+ unsigned long i;
+ int ret = 0;
+ unsigned from, to;
+
+ if (sbi->s_cluster_ratio <= 1)
+ goto out;
+
+ if (right_offset) {
+ struct ext4_map_blocks map;
+ map.m_lblk = last_block;
+ map.m_len = 1;
+ if (ext4_map_blocks(handle, inode, &map, 0) <= 0
+ || map.m_flags & EXT4_MAP_UNWRITTEN)
+ goto out;
+
+ ewcc = ext4_alloc_write_cluster_ctxt();
+ if (!ewcc) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ begin = last_block + 1;
+ for (index = begin; index < last_block + right_offset + 1;
+ index++) {
+ ret = ext4_zero_cluster_page(inode, index, ewcc,
+ mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
+ if (ret)
+ goto out;
+ }
+
+ if (ext4_should_journal_data(inode)) {
+ for (i = 0; i < ewcc->w_num_pages; i++) {
+ page = ewcc->w_pages[i];
+ if (!page || !page_buffers(page))
+ continue;
+ from = page->index << PAGE_CACHE_SHIFT;
+ to = from + PAGE_CACHE_SIZE;
+ ret = walk_page_buffers(handle,
+ page_buffers(page), from, to, NULL,
+ do_journal_get_write_access);
+ if (ret)
+ goto out;
+ }
+ }
+ }
+
+out:
+ if (ewcc)
+ ext4_free_write_cluster_ctxt(ewcc);
+
+ return ret;
+}
+
+void ext4_ext_truncate(struct inode *inode, loff_t old_size)
{
struct address_space *mapping = inode->i_mapping;
struct super_block *sb = inode->i_sb;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
ext4_lblk_t last_block;
handle_t *handle;
int err = 0;
@@ -4176,6 +4242,13 @@ void ext4_ext_truncate(struct inode *inode)
last_block = (inode->i_size + sb->s_blocksize - 1)
>> EXT4_BLOCK_SIZE_BITS(sb);
+
+ if (sbi->s_cluster_ratio > 1 &&
+ (last_block & (sbi->s_cluster_ratio - 1))) {
+ last_block = (last_block & ~(sbi->s_cluster_ratio - 1)) +
+ sbi->s_cluster_ratio;
+ }
+
err = ext4_ext_remove_space(inode, last_block);
/* In a multi-transaction truncate, we only make the final
@@ -4186,6 +4259,9 @@ void ext4_ext_truncate(struct inode *inode)
up_write(&EXT4_I(inode)->i_data_sem);
+ if (ext4_ext_truncate_zero_pages(handle, inode, old_size))
+ goto out_stop;
+
out_stop:
/*
* If this was a simple ftruncate() and the file will remain alive,
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index f1c332d..22b28bd 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -213,7 +213,7 @@ void ext4_evict_inode(struct inode *inode)
goto stop_handle;
}
if (inode->i_blocks)
- ext4_truncate(inode);
+ ext4_truncate(inode, 0);
/*
* ext4_ext_truncate() doesn't reserve any slop when it
@@ -3440,7 +3440,7 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length)
* that's fine - as long as they are linked from the inode, the post-crash
* ext4_truncate() run will find them and release them.
*/
-void ext4_truncate(struct inode *inode)
+void ext4_truncate(struct inode *inode, loff_t old_size)
{
trace_ext4_truncate_enter(inode);
@@ -3453,7 +3453,7 @@ void ext4_truncate(struct inode *inode)
ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
- ext4_ext_truncate(inode);
+ ext4_ext_truncate(inode, old_size);
else
ext4_ind_truncate(inode);
@@ -4220,11 +4220,12 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
}
if (attr->ia_valid & ATTR_SIZE) {
- if (attr->ia_size != i_size_read(inode)) {
+ loff_t old_size = i_size_read(inode);
+ if (attr->ia_size != old_size) {
truncate_setsize(inode, attr->ia_size);
- ext4_truncate(inode);
+ ext4_truncate(inode, old_size);
} else if (ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
- ext4_truncate(inode);
+ ext4_truncate(inode, 0);
}
if (!rc) {
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 4a5081a..6eb2f4f 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -100,7 +100,7 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
goto flags_out;
}
} else if (oldflags & EXT4_EOFBLOCKS_FL)
- ext4_truncate(inode);
+ ext4_truncate(inode, 0);
handle = ext4_journal_start(inode, 1);
if (IS_ERR(handle)) {
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 2cf4ae0..beea7a1 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2229,7 +2229,7 @@ static void ext4_orphan_cleanup(struct super_block *sb,
__func__, inode->i_ino, inode->i_size);
jbd_debug(2, "truncating inode %lu to %lld bytes\n",
inode->i_ino, inode->i_size);
- ext4_truncate(inode);
+ ext4_truncate(inode, 0);
nr_truncates++;
} else {
ext4_msg(sb, KERN_DEBUG,
diff --git a/fs/ext4/truncate.h b/fs/ext4/truncate.h
index 011ba66..2be0783 100644
--- a/fs/ext4/truncate.h
+++ b/fs/ext4/truncate.h
@@ -11,7 +11,7 @@
static inline void ext4_truncate_failed_write(struct inode *inode)
{
truncate_inode_pages(inode->i_mapping, inode->i_size);
- ext4_truncate(inode);
+ ext4_truncate(inode, 0);
}
/*
--
1.7.3.2
--
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