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Message-ID: <20141025205857.532.33229.stgit@birch.djwong.org>
Date: Sat, 25 Oct 2014 13:58:57 -0700
From: "Darrick J. Wong" <darrick.wong@...cle.com>
To: tytso@....edu, darrick.wong@...cle.com
Cc: linux-ext4@...r.kernel.org
Subject: [PATCH 24/39] libext2fs/e2fsck: refactor everyone who writes zero
blocks to disk
Convert all call sites that write zero blocks to disk to use
ext2fs_zero_blocks2() since it can use Linux's zero out feature to do
the writes more quickly. Reclaim the zero buffer at freefs time and
make the write-zeroes fallback use a larger buffer.
Signed-off-by: Darrick J. Wong <darrick.wong@...cle.com>
---
e2fsck/e2fsck.h | 2 -
e2fsck/pass1.c | 13 +++++---
e2fsck/pass3.c | 13 ++------
e2fsck/util.c | 53 ----------------------------------
lib/ext2fs/alloc.c | 14 ++-------
lib/ext2fs/expanddir.c | 13 ++------
lib/ext2fs/ext2fs.h | 3 ++
lib/ext2fs/freefs.c | 1 +
lib/ext2fs/mkjournal.c | 75 +++++++++++++++++++++++++++++++++++-------------
misc/mke2fs.c | 2 -
resize/resize2fs.c | 25 ++++++----------
11 files changed, 84 insertions(+), 130 deletions(-)
diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
index b2654ef..e359515 100644
--- a/e2fsck/e2fsck.h
+++ b/e2fsck/e2fsck.h
@@ -544,8 +544,6 @@ extern void e2fsck_read_bitmaps(e2fsck_t ctx);
extern void e2fsck_write_bitmaps(e2fsck_t ctx);
extern void preenhalt(e2fsck_t ctx);
extern char *string_copy(e2fsck_t ctx, const char *str, int len);
-extern errcode_t e2fsck_zero_blocks(ext2_filsys fs, blk_t blk, int num,
- blk_t *ret_blk, int *ret_count);
extern int fs_proc_check(const char *fs_name);
extern int check_for_modules(const char *fs_name);
#ifdef RESOURCE_TRACK
diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index d4760ef..a963849 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -3576,12 +3576,15 @@ static void new_table_block(e2fsck_t ctx, blk64_t first_block, dgrp_t group,
old_block + i, 1, buf);
if (pctx.errcode)
fix_problem(ctx, PR_1_RELOC_READ_ERR, &pctx);
- } else
- memset(buf, 0, fs->blocksize);
+ pctx.blk = (*new_block) + i;
+ pctx.errcode = io_channel_write_blk64(fs->io, pctx.blk,
+ 1, buf);
+ } else {
+ pctx.blk = (*new_block) + i;
+ pctx.errcode = ext2fs_zero_blocks2(fs, pctx.blk, 1,
+ NULL, NULL);
+ }
- pctx.blk = (*new_block) + i;
- pctx.errcode = io_channel_write_blk64(fs->io, pctx.blk,
- 1, buf);
if (pctx.errcode)
fix_problem(ctx, PR_1_RELOC_WRITE_ERR, &pctx);
}
diff --git a/e2fsck/pass3.c b/e2fsck/pass3.c
index f03c7ae..2d94ece 100644
--- a/e2fsck/pass3.c
+++ b/e2fsck/pass3.c
@@ -809,20 +809,13 @@ static int expand_dir_proc(ext2_filsys fs,
es->num--;
retval = ext2fs_write_dir_block4(fs, new_blk, block, 0,
es->dir);
- } else {
- retval = ext2fs_get_mem(fs->blocksize, &block);
- if (retval) {
- es->err = retval;
- return BLOCK_ABORT;
- }
- memset(block, 0, fs->blocksize);
- retval = io_channel_write_blk64(fs->io, new_blk, 1, block);
- }
+ ext2fs_free_mem(&block);
+ } else
+ retval = ext2fs_zero_blocks2(fs, new_blk, 1, NULL, NULL);
if (retval) {
es->err = retval;
return BLOCK_ABORT;
}
- ext2fs_free_mem(&block);
*blocknr = new_blk;
ext2fs_mark_block_bitmap2(ctx->block_found_map, new_blk);
diff --git a/e2fsck/util.c b/e2fsck/util.c
index 74f20062..723dafb 100644
--- a/e2fsck/util.c
+++ b/e2fsck/util.c
@@ -612,59 +612,6 @@ int ext2_file_type(unsigned int mode)
return 0;
}
-#define STRIDE_LENGTH 8
-/*
- * Helper function which zeros out _num_ blocks starting at _blk_. In
- * case of an error, the details of the error is returned via _ret_blk_
- * and _ret_count_ if they are non-NULL pointers. Returns 0 on
- * success, and an error code on an error.
- *
- * As a special case, if the first argument is NULL, then it will
- * attempt to free the static zeroizing buffer. (This is to keep
- * programs that check for memory leaks happy.)
- */
-errcode_t e2fsck_zero_blocks(ext2_filsys fs, blk_t blk, int num,
- blk_t *ret_blk, int *ret_count)
-{
- int j, count;
- static char *buf;
- errcode_t retval;
-
- /* If fs is null, clean up the static buffer and return */
- if (!fs) {
- if (buf) {
- free(buf);
- buf = 0;
- }
- return 0;
- }
- /* Allocate the zeroizing buffer if necessary */
- if (!buf) {
- buf = malloc(fs->blocksize * STRIDE_LENGTH);
- if (!buf) {
- com_err("malloc", ENOMEM, "%s",
- _("while allocating zeroizing buffer"));
- exit(1);
- }
- memset(buf, 0, fs->blocksize * STRIDE_LENGTH);
- }
- /* OK, do the write loop */
- for (j = 0; j < num; j += STRIDE_LENGTH, blk += STRIDE_LENGTH) {
- count = num - j;
- if (count > STRIDE_LENGTH)
- count = STRIDE_LENGTH;
- retval = io_channel_write_blk64(fs->io, blk, count, buf);
- if (retval) {
- if (ret_count)
- *ret_count = count;
- if (ret_blk)
- *ret_blk = blk;
- return retval;
- }
- }
- return 0;
-}
-
/*
* Check to see if a filesystem is in /proc/filesystems.
* Returns 1 if found, 0 if not
diff --git a/lib/ext2fs/alloc.c b/lib/ext2fs/alloc.c
index d1c1a84..82af18e 100644
--- a/lib/ext2fs/alloc.c
+++ b/lib/ext2fs/alloc.c
@@ -198,15 +198,9 @@ errcode_t ext2fs_alloc_block2(ext2_filsys fs, blk64_t goal,
{
errcode_t retval;
blk64_t block;
- char *buf = 0;
- if (!block_buf) {
- retval = ext2fs_get_mem(fs->blocksize, &buf);
- if (retval)
- return retval;
- block_buf = buf;
- }
- memset(block_buf, 0, fs->blocksize);
+ if (block_buf)
+ memset(block_buf, 0, fs->blocksize);
if (fs->get_alloc_block) {
retval = (fs->get_alloc_block)(fs, goal, &block);
@@ -224,7 +218,7 @@ errcode_t ext2fs_alloc_block2(ext2_filsys fs, blk64_t goal,
goto fail;
}
- retval = io_channel_write_blk64(fs->io, block, 1, block_buf);
+ retval = ext2fs_zero_blocks3(fs, block, 1, NULL, NULL, block_buf);
if (retval)
goto fail;
@@ -232,8 +226,6 @@ errcode_t ext2fs_alloc_block2(ext2_filsys fs, blk64_t goal,
*ret = block;
fail:
- if (buf)
- ext2fs_free_mem(&buf);
return retval;
}
diff --git a/lib/ext2fs/expanddir.c b/lib/ext2fs/expanddir.c
index d0f7287..ecc13ae 100644
--- a/lib/ext2fs/expanddir.c
+++ b/lib/ext2fs/expanddir.c
@@ -67,22 +67,15 @@ static int expand_dir_proc(ext2_filsys fs,
es->done = 1;
retval = ext2fs_write_dir_block4(fs, new_blk, block, 0,
es->dir);
- } else {
- retval = ext2fs_get_mem(fs->blocksize, &block);
- if (retval) {
- es->err = retval;
- return BLOCK_ABORT;
- }
- memset(block, 0, fs->blocksize);
- retval = io_channel_write_blk64(fs->io, new_blk, 1, block);
- }
+ ext2fs_free_mem(&block);
+ } else
+ retval = ext2fs_zero_blocks2(fs, new_blk, 1, NULL, NULL);
if (blockcnt >= 0)
es->goal = new_blk;
if (retval) {
es->err = retval;
return BLOCK_ABORT;
}
- ext2fs_free_mem(&block);
*blocknr = new_blk;
if (es->done)
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 689f6a6..5ecaa85 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -1504,6 +1504,9 @@ extern errcode_t ext2fs_zero_blocks(ext2_filsys fs, blk_t blk, int num,
blk_t *ret_blk, int *ret_count);
extern errcode_t ext2fs_zero_blocks2(ext2_filsys fs, blk64_t blk, int num,
blk64_t *ret_blk, int *ret_count);
+extern errcode_t ext2fs_zero_blocks3(ext2_filsys fs, blk64_t blk, int num,
+ blk64_t *ret_blk, int *ret_count,
+ const void *block_buf);
extern errcode_t ext2fs_create_journal_superblock(ext2_filsys fs,
__u32 num_blocks, int flags,
char **ret_jsb);
diff --git a/lib/ext2fs/freefs.c b/lib/ext2fs/freefs.c
index 89a157b..ea9742e 100644
--- a/lib/ext2fs/freefs.c
+++ b/lib/ext2fs/freefs.c
@@ -61,6 +61,7 @@ void ext2fs_free(ext2_filsys fs)
fs->magic = 0;
+ ext2fs_zero_blocks2(NULL, 0, 0, NULL, NULL);
ext2fs_free_mem(&fs);
}
diff --git a/lib/ext2fs/mkjournal.c b/lib/ext2fs/mkjournal.c
index 5be425c..2cd7ca5 100644
--- a/lib/ext2fs/mkjournal.c
+++ b/lib/ext2fs/mkjournal.c
@@ -148,12 +148,14 @@ errfree:
* attempt to free the static zeroizing buffer. (This is to keep
* programs that check for memory leaks happy.)
*/
-#define STRIDE_LENGTH 8
-errcode_t ext2fs_zero_blocks2(ext2_filsys fs, blk64_t blk, int num,
- blk64_t *ret_blk, int *ret_count)
+#define MAX_STRIDE_LENGTH (4194304 / fs->blocksize)
+errcode_t ext2fs_zero_blocks3(ext2_filsys fs, blk64_t blk, int num,
+ blk64_t *ret_blk, int *ret_count,
+ const void *block_buf)
{
int j, count;
- static char *buf;
+ static void *buf;
+ static unsigned stride_length;
errcode_t retval;
/* If fs is null, clean up the static buffer and return */
@@ -165,29 +167,56 @@ errcode_t ext2fs_zero_blocks2(ext2_filsys fs, blk64_t blk, int num,
return 0;
}
+ /* Deal with zeroing less than 1 block */
+ if (num <= 0)
+ return 0;
+
/* Try a zero out command, if supported */
retval = io_channel_zeroout(fs->io, blk, num);
if (retval == 0)
return 0;
+ /* If the user gave us a buffer, write that out */
+ if (block_buf) {
+ retval = io_channel_write_blk64(fs->io, blk, num, block_buf);
+ if (retval) {
+ if (ret_count)
+ *ret_count = num;
+ if (ret_blk)
+ *ret_blk = blk;
+ }
+
+ return retval;
+ }
+
/* Allocate the zeroizing buffer if necessary */
- if (!buf) {
- buf = malloc(fs->blocksize * STRIDE_LENGTH);
- if (!buf)
- return ENOMEM;
- memset(buf, 0, fs->blocksize * STRIDE_LENGTH);
+ if (num > stride_length) {
+ void *p;
+ unsigned new_stride = num;
+
+ if (new_stride > MAX_STRIDE_LENGTH)
+ new_stride = MAX_STRIDE_LENGTH;
+ if (new_stride == stride_length)
+ goto skip_alloc;
+ p = realloc(buf, fs->blocksize * new_stride);
+ if (!p)
+ return EXT2_ET_NO_MEMORY;
+ buf = p;
+ stride_length = new_stride;
+ memset(buf, 0, fs->blocksize * stride_length);
}
+skip_alloc:
/* OK, do the write loop */
j=0;
while (j < num) {
- if (blk % STRIDE_LENGTH) {
- count = STRIDE_LENGTH - (blk % STRIDE_LENGTH);
+ if (blk % stride_length) {
+ count = stride_length - (blk % stride_length);
if (count > (num - j))
count = num - j;
} else {
count = num - j;
- if (count > STRIDE_LENGTH)
- count = STRIDE_LENGTH;
+ if (count > stride_length)
+ count = stride_length;
}
retval = io_channel_write_blk64(fs->io, blk, count, buf);
if (retval) {
@@ -202,6 +231,12 @@ errcode_t ext2fs_zero_blocks2(ext2_filsys fs, blk64_t blk, int num,
return 0;
}
+errcode_t ext2fs_zero_blocks2(ext2_filsys fs, blk64_t blk, int num,
+ blk64_t *ret_blk, int *ret_count)
+{
+ return ext2fs_zero_blocks3(fs, blk, num, ret_blk, ret_count, NULL);
+}
+
errcode_t ext2fs_zero_blocks(ext2_filsys fs, blk_t blk, int num,
blk_t *ret_blk, int *ret_count)
{
@@ -372,20 +407,20 @@ static errcode_t write_journal_inode(ext2_filsys fs, ext2_ino_t journal_ino,
retval = ext2fs_block_iterate3(fs, journal_ino, BLOCK_FLAG_APPEND,
0, mkjournal_proc, &es);
if (retval)
- goto errout;
+ goto out2;
if (es.err) {
retval = es.err;
- goto errout;
+ goto out2;
}
if (es.zero_count) {
retval = ext2fs_zero_blocks2(fs, es.blk_to_zero,
es.zero_count, 0, 0);
if (retval)
- goto errout;
+ goto out2;
}
if ((retval = ext2fs_read_inode(fs, journal_ino, &inode)))
- goto errout;
+ goto out2;
inode_size = (unsigned long long)fs->blocksize * num_blocks;
ext2fs_iblk_add_blocks(fs, &inode, es.newblocks);
@@ -394,10 +429,10 @@ static errcode_t write_journal_inode(ext2_filsys fs, ext2_ino_t journal_ino,
inode.i_mode = LINUX_S_IFREG | 0600;
retval = ext2fs_inode_size_set(fs, &inode, inode_size);
if (retval)
- goto errout;
+ goto out2;
if ((retval = ext2fs_write_new_inode(fs, journal_ino, &inode)))
- goto errout;
+ goto out2;
retval = 0;
memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
@@ -406,8 +441,6 @@ static errcode_t write_journal_inode(ext2_filsys fs, ext2_ino_t journal_ino,
fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
ext2fs_mark_super_dirty(fs);
-errout:
- ext2fs_zero_blocks2(0, 0, 0, 0, 0);
out2:
ext2fs_free_mem(&buf);
return retval;
diff --git a/misc/mke2fs.c b/misc/mke2fs.c
index c6a2c2f..149330c 100644
--- a/misc/mke2fs.c
+++ b/misc/mke2fs.c
@@ -437,7 +437,6 @@ static void write_inode_tables(ext2_filsys fs, int lazy_flag, int itable_zeroed)
sync();
}
}
- ext2fs_zero_blocks2(0, 0, 0, 0, 0);
ext2fs_numeric_progress_close(fs, &progress,
_("done \n"));
@@ -626,7 +625,6 @@ static void create_journal_dev(ext2_filsys fs)
count -= c;
ext2fs_numeric_progress_update(fs, &progress, blk);
}
- ext2fs_zero_blocks2(0, 0, 0, 0, 0);
ext2fs_numeric_progress_close(fs, &progress, NULL);
write_superblock:
diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index e71acf3..93df070 100644
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -762,11 +762,11 @@ static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
/*
* Write out the new inode table
*/
- retval = io_channel_write_blk64(fs->io,
- ext2fs_inode_table_loc(fs, i),
- fs->inode_blocks_per_group,
- rfs->itable_buf);
- if (retval) goto errout;
+ retval = ext2fs_zero_blocks2(fs, ext2fs_inode_table_loc(fs, i),
+ fs->inode_blocks_per_group, NULL,
+ NULL);
+ if (retval)
+ goto errout;
io_channel_flush(fs->io);
if (rfs->progress) {
@@ -2244,15 +2244,11 @@ static errcode_t fix_resize_inode(ext2_filsys fs)
{
struct ext2_inode inode;
errcode_t retval;
- char *block_buf = NULL;
if (!(fs->super->s_feature_compat &
EXT2_FEATURE_COMPAT_RESIZE_INODE))
return 0;
- retval = ext2fs_get_mem(fs->blocksize, &block_buf);
- if (retval) goto errout;
-
retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
if (retval) goto errout;
@@ -2272,19 +2268,16 @@ static errcode_t fix_resize_inode(ext2_filsys fs)
exit(1);
}
- memset(block_buf, 0, fs->blocksize);
-
- retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
- 1, block_buf);
- if (retval) goto errout;
+ retval = ext2fs_zero_blocks2(fs, inode.i_block[EXT2_DIND_BLOCK], 1,
+ NULL, NULL);
+ if (retval)
+ goto errout;
retval = ext2fs_create_resize_inode(fs);
if (retval)
goto errout;
errout:
- if (block_buf)
- ext2fs_free_mem(&block_buf);
return retval;
}
--
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