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Date: Wed, 15 Feb 2017 20:45:00 +0300
From: Artem Blagodarenko <artem.blagodarenko@...il.com>
To: linux-ext4@...r.kernel.org
Cc: adilger.kernel@...ger.ca
Subject: [PATCH v4 3/4] e2fsck: 3 level hash tree directory optimization
From: Artem Blagodarenko <artem.blagodarenko@...gate.com>
e2fsck fix for partitions with 3 level hash directries.
Additional level is added to e2fsck -D codepath.
Signed-off-by: Artem Blagodarenko <artem.blagodarenko@...gate.com>
---
debugfs/htree.c | 3 +-
e2fsck/e2fsck.h | 1 +
e2fsck/pass2.c | 68 ++++++++++++++++++++++--------
e2fsck/rehash.c | 115 ++++++++++++++++++++++++++++++++++++++++-----------
lib/ext2fs/ext2fs.h | 5 ++
5 files changed, 148 insertions(+), 44 deletions(-)
diff --git a/debugfs/htree.c b/debugfs/htree.c
index 54e55e2..8c18666 100644
--- a/debugfs/htree.c
+++ b/debugfs/htree.c
@@ -287,7 +287,8 @@ void do_htree_dump(int argc, char *argv[])
fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
- ent = (struct ext2_dx_entry *) (buf + 24 + rootnode->info_length);
+ ent = (struct ext2_dx_entry *)
+ ((char *)rootnode + rootnode->info_length);
htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
buf + current_fs->blocksize,
diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
index f356810..a4efbdf 100644
--- a/e2fsck/e2fsck.h
+++ b/e2fsck/e2fsck.h
@@ -122,6 +122,7 @@ struct dx_dirblock_info {
blk64_t phys;
int flags;
blk64_t parent;
+ blk64_t previous;
ext2_dirhash_t min_hash;
ext2_dirhash_t max_hash;
ext2_dirhash_t node_min_hash;
diff --git a/e2fsck/pass2.c b/e2fsck/pass2.c
index 2f41fc4..c1c4e48 100644
--- a/e2fsck/pass2.c
+++ b/e2fsck/pass2.c
@@ -85,6 +85,39 @@ struct check_dir_struct {
unsigned long long next_ra_off;
};
+static void update_parents(struct dx_dir_info *dx_dir, int type)
+{
+ struct dx_dirblock_info *dx_db, *dx_parent, *dx_previous;
+ int b;
+
+ for (b = 0, dx_db = dx_dir->dx_block;
+ b < dx_dir->numblocks;
+ b++, dx_db++) {
+ dx_parent = &dx_dir->dx_block[dx_db->parent];
+ if (dx_db->type != type)
+ continue;
+
+ /*
+ * XXX Make sure dx_parent->min_hash > dx_db->min_hash
+ */
+ if (dx_db->flags & DX_FLAG_FIRST) {
+ dx_parent->min_hash = dx_db->min_hash;
+ if (dx_parent->previous) {
+ dx_previous =
+ &dx_dir->dx_block[dx_parent->previous];
+ dx_previous->node_max_hash =
+ dx_parent->min_hash;
+ }
+ }
+ /*
+ * XXX Make sure dx_parent->max_hash < dx_db->max_hash
+ */
+ if (dx_db->flags & DX_FLAG_LAST) {
+ dx_parent->max_hash = dx_db->max_hash;
+ }
+ }
+}
+
void e2fsck_pass2(e2fsck_t ctx)
{
struct ext2_super_block *sb = ctx->fs->super;
@@ -182,24 +215,11 @@ void e2fsck_pass2(e2fsck_t ctx)
* Find all of the first and last leaf blocks, and
* update their parent's min and max hash values
*/
- for (b=0, dx_db = dx_dir->dx_block;
- b < dx_dir->numblocks;
- b++, dx_db++) {
- if ((dx_db->type != DX_DIRBLOCK_LEAF) ||
- !(dx_db->flags & (DX_FLAG_FIRST | DX_FLAG_LAST)))
- continue;
- dx_parent = &dx_dir->dx_block[dx_db->parent];
- /*
- * XXX Make sure dx_parent->min_hash > dx_db->min_hash
- */
- if (dx_db->flags & DX_FLAG_FIRST)
- dx_parent->min_hash = dx_db->min_hash;
- /*
- * XXX Make sure dx_parent->max_hash < dx_db->max_hash
- */
- if (dx_db->flags & DX_FLAG_LAST)
- dx_parent->max_hash = dx_db->max_hash;
- }
+ update_parents(dx_dir, DX_DIRBLOCK_LEAF);
+
+ /* for 3 level htree: update 2 level parent's min
+ * and max hash values */
+ update_parents(dx_dir, DX_DIRBLOCK_NODE);
for (b=0, dx_db = dx_dir->dx_block;
b < dx_dir->numblocks;
@@ -642,6 +662,10 @@ static void parse_int_node(ext2_filsys fs,
dx_db->flags |= DX_FLAG_REFERENCED;
dx_db->parent = db->blockcnt;
}
+
+ dx_db->previous =
+ i ? ext2fs_le32_to_cpu(ent[i-1].block & 0x0ffffff) : 0;
+
if (hash < min_hash)
min_hash = hash;
if (hash > max_hash)
@@ -949,6 +973,14 @@ static int check_dir_block(ext2_filsys fs,
return DIRENT_ABORT;
}
+ /* This will allow (at some point in the future) to punch out empty
+ * directory blocks and reduce the space used by a directory that grows
+ * very large and then the files are deleted. For now, all that is
+ * needed is to avoid e2fsck filling in these holes as part of
+ * feature flag. */
+ if (db->blk == 0 && ext2fs_has_feature_largedir(fs))
+ return 0;
+
if (db->blk == 0 && !inline_data_size) {
if (allocate_dir_block(ctx, db, buf, &cd->pctx))
return 0;
diff --git a/e2fsck/rehash.c b/e2fsck/rehash.c
index 22a58f3..7dcb386 100644
--- a/e2fsck/rehash.c
+++ b/e2fsck/rehash.c
@@ -603,6 +603,43 @@ static struct ext2_dx_entry *set_int_node(ext2_filsys fs, char *buf)
return (struct ext2_dx_entry *) limits;
}
+static int alloc_blocks(ext2_filsys fs,
+ struct ext2_dx_countlimit **limit,
+ struct ext2_dx_entry **prev_ent,
+ struct ext2_dx_entry **next_ent,
+ int *prev_offset, int *next_offset,
+ struct out_dir *outdir, int i,
+ int *prev_count, int *next_count)
+{
+ errcode_t retval;
+ char *block_start;
+
+ if (*limit)
+ (*limit)->limit = (*limit)->count =
+ ext2fs_cpu_to_le16((*limit)->limit);
+ *prev_ent = (struct ext2_dx_entry *) (outdir->buf + *prev_offset);
+ (*prev_ent)->block = ext2fs_cpu_to_le32(outdir->num);
+
+ if (i != 1)
+ (*prev_ent)->hash =
+ ext2fs_cpu_to_le32(outdir->hashes[i]);
+
+ retval = get_next_block(fs, outdir, &block_start);
+ if (retval)
+ return retval;
+
+ *next_ent = set_int_node(fs, block_start);
+ *limit = (struct ext2_dx_countlimit *)(*next_ent);
+ if (next_offset)
+ *next_offset = ((char *) *next_ent - outdir->buf);
+
+ *next_count = (*limit)->limit;
+ (*prev_offset) += sizeof(struct ext2_dx_entry);
+ (*prev_count)--;
+
+ return 0;
+}
+
/*
* This function takes the leaf nodes which have been written in
* outdir, and populates the root node and any necessary interior nodes.
@@ -612,13 +649,13 @@ static errcode_t calculate_tree(ext2_filsys fs,
ext2_ino_t ino,
ext2_ino_t parent)
{
- struct ext2_dx_root_info *root_info;
- struct ext2_dx_entry *root, *dx_ent = 0;
- struct ext2_dx_countlimit *root_limit, *limit;
+ struct ext2_dx_root_info *root_info;
+ struct ext2_dx_entry *root, *int_ent, *dx_ent = 0;
+ struct ext2_dx_countlimit *root_limit, *int_limit, *limit;
errcode_t retval;
char * block_start;
- int i, c1, c2, nblks;
- int limit_offset, root_offset;
+ int i, c1, c2, c3, nblks;
+ int limit_offset, int_offset, root_offset;
root_info = set_root_node(fs, outdir->buf, ino, parent);
root_offset = limit_offset = ((char *) root_info - outdir->buf) +
@@ -628,7 +665,7 @@ static errcode_t calculate_tree(ext2_filsys fs,
nblks = outdir->num;
/* Write out the pointer blocks */
- if (nblks-1 <= c1) {
+ if (nblks - 1 <= c1) {
/* Just write out the root block, and we're done */
root = (struct ext2_dx_entry *) (outdir->buf + root_offset);
for (i=1; i < nblks; i++) {
@@ -639,31 +676,20 @@ static errcode_t calculate_tree(ext2_filsys fs,
root++;
c1--;
}
- } else {
+ } else if (nblks - 1 <= ext2fs_htree_intnode_maxrecs(fs, c1)) {
c2 = 0;
- limit = 0;
+ limit = NULL;
root_info->indirect_levels = 1;
for (i=1; i < nblks; i++) {
- if (c1 == 0)
+ if (c2 == 0 && c1 == 0)
return ENOSPC;
if (c2 == 0) {
- if (limit)
- limit->limit = limit->count =
- ext2fs_cpu_to_le16(limit->limit);
- root = (struct ext2_dx_entry *)
- (outdir->buf + root_offset);
- root->block = ext2fs_cpu_to_le32(outdir->num);
- if (i != 1)
- root->hash =
- ext2fs_cpu_to_le32(outdir->hashes[i]);
- if ((retval = get_next_block(fs, outdir,
- &block_start)))
+ retval = alloc_blocks(fs, &limit, &root,
+ &dx_ent, &root_offset,
+ NULL, outdir, i, &c1,
+ &c2);
+ if (retval)
return retval;
- dx_ent = set_int_node(fs, block_start);
- limit = (struct ext2_dx_countlimit *) dx_ent;
- c2 = limit->limit;
- root_offset += sizeof(struct ext2_dx_entry);
- c1--;
}
dx_ent->block = ext2fs_cpu_to_le32(i);
if (c2 != limit->limit)
@@ -674,6 +700,45 @@ static errcode_t calculate_tree(ext2_filsys fs,
}
limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
limit->limit = ext2fs_cpu_to_le16(limit->limit);
+ } else {
+ c2 = 0;
+ c3 = 0;
+ limit = NULL;
+ int_limit = 0;
+ root_info->indirect_levels = 2;
+ for (i = 1; i < nblks; i++) {
+ if (c3 == 0 && c2 == 0 && c1 == 0)
+ return ENOSPC;
+ if (c3 == 0 && c2 == 0) {
+ retval = alloc_blocks(fs, &int_limit, &root,
+ &int_ent, &root_offset,
+ &int_offset, outdir, i,
+ &c1, &c2);
+ if (retval)
+ return retval;
+ }
+ if (c3 == 0) {
+ retval = alloc_blocks(fs, &limit, &int_ent,
+ &dx_ent, &int_offset,
+ NULL, outdir, i, &c2,
+ &c3);
+ if (retval)
+ return retval;
+
+ }
+ dx_ent->block = ext2fs_cpu_to_le32(i);
+ if (c3 != limit->limit)
+ dx_ent->hash =
+ ext2fs_cpu_to_le32(outdir->hashes[i]);
+ dx_ent++;
+ c3--;
+ }
+ int_limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
+ int_limit->limit = ext2fs_cpu_to_le16(limit->limit);
+
+ limit->count = ext2fs_cpu_to_le16(limit->limit - c3);
+ limit->limit = ext2fs_cpu_to_le16(limit->limit);
+
}
root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
root_limit->count = ext2fs_cpu_to_le16(root_limit->limit - c1);
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index c68be50..baa422c 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -1937,6 +1937,11 @@ static inline unsigned int ext2_dir_htree_level(ext2_filsys fs)
return EXT4_HTREE_LEVEL_COMPAT;
}
+_INLINE_ int ext2fs_htree_intnode_maxrecs(ext2_filsys fs, int blocks)
+{
+ return blocks * ((fs->blocksize - 8) / sizeof(struct ext2_dx_entry));
+}
+
/*
* This is an efficient, overflow safe way of calculating ceil((1.0 * a) / b)
*/
--
1.7.1
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