Add support for creating and deleting orphan file and a couple of
utility functions that will be used in other tools.
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
lib/e2p/feature.c | 4 +
lib/ext2fs/Makefile.in | 2 +
lib/ext2fs/ext2_fs.h | 11 +++
lib/ext2fs/ext2fs.h | 29 ++++++-
lib/ext2fs/orphan.c | 227 +++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 271 insertions(+), 2 deletions(-)
create mode 100644 lib/ext2fs/orphan.c
diff --git a/lib/e2p/feature.c b/lib/e2p/feature.c
index 73884f2cf5bf..a8e0d4a4644a 100644
--- a/lib/e2p/feature.c
+++ b/lib/e2p/feature.c
@@ -45,6 +45,8 @@ static struct feature feature_list[] = {
"snapshot_bitmap" },
{ E2P_FEATURE_COMPAT, EXT4_FEATURE_COMPAT_SPARSE_SUPER2,
"sparse_super2" },
+ { E2P_FEATURE_COMPAT, EXT4_FEATURE_COMPAT_ORPHAN_FILE,
+ "orphan_file" },
{ E2P_FEATURE_RO_INCOMPAT, EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER,
"sparse_super" },
@@ -70,6 +72,8 @@ static struct feature feature_list[] = {
"replica" },
{ E2P_FEATURE_RO_INCOMPAT, EXT4_FEATURE_RO_COMPAT_READONLY,
"read-only" },
+ { E2P_FEATURE_RO_INCOMPAT, EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT,
+ "orphan_file_used" },
{ E2P_FEATURE_INCOMPAT, EXT2_FEATURE_INCOMPAT_COMPRESSION,
"compression" },
diff --git a/lib/ext2fs/Makefile.in b/lib/ext2fs/Makefile.in
index 8a7f8ca52902..67120b10438c 100644
--- a/lib/ext2fs/Makefile.in
+++ b/lib/ext2fs/Makefile.in
@@ -109,6 +109,7 @@ OBJS= $(DEBUGFS_LIB_OBJS) $(RESIZE_LIB_OBJS) $(E2IMAGE_LIB_OBJS) \
native.o \
newdir.o \
openfs.o \
+ orphan.o \
progress.o \
punch.o \
qcow2.o \
@@ -189,6 +190,7 @@ SRCS= ext2_err.c \
$(srcdir)/native.c \
$(srcdir)/newdir.c \
$(srcdir)/openfs.c \
+ $(srcdir)/orphan.c \
$(srcdir)/progress.c \
$(srcdir)/punch.c \
$(srcdir)/qcow2.c \
diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
index a755cfac8eae..a77c8fa09938 100644
--- a/lib/ext2fs/ext2_fs.h
+++ b/lib/ext2fs/ext2_fs.h
@@ -52,6 +52,7 @@
#define EXT2_JOURNAL_INO 8 /* Journal inode */
#define EXT2_EXCLUDE_INO 9 /* The "exclude" inode, for snapshots */
#define EXT4_REPLICA_INO 10 /* Used by non-upstream feature */
+#define EXT4_ORPHAN_INO 9 /* Inode with orphan entries */
/* First non-reserved inode for old ext2 filesystems */
#define EXT2_GOOD_OLD_FIRST_INO 11
@@ -769,6 +770,7 @@ struct ext2_super_block {
/* #define EXT2_FEATURE_COMPAT_EXCLUDE_INODE 0x0080 not used, legacy */
#define EXT2_FEATURE_COMPAT_EXCLUDE_BITMAP 0x0100
#define EXT4_FEATURE_COMPAT_SPARSE_SUPER2 0x0200
+#define EXT4_FEATURE_COMPAT_ORPHAN_FILE 0x0400
#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
@@ -789,6 +791,7 @@ struct ext2_super_block {
#define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
#define EXT4_FEATURE_RO_COMPAT_REPLICA 0x0800
#define EXT4_FEATURE_RO_COMPAT_READONLY 0x1000
+#define EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT 0x2000
#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
@@ -838,6 +841,14 @@ struct ext2_super_block {
#define EXT4_DEFM_DISCARD 0x0400
#define EXT4_DEFM_NODELALLOC 0x0800
+#define EXT4_ORPHAN_BLOCK_MAGIC 0x0b10ca04
+
+/* Structure at the tail of orphan block */
+struct ext4_orphan_block_tail {
+ __u32 ob_magic;
+ __u32 ob_checksum;
+};
+
/*
* Structure of a directory entry
*/
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 28c46701da29..291a74f5ea2f 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -555,7 +555,8 @@ typedef struct ext2_icount *ext2_icount_t;
EXT2_FEATURE_COMPAT_RESIZE_INODE|\
EXT2_FEATURE_COMPAT_DIR_INDEX|\
EXT2_FEATURE_COMPAT_EXT_ATTR|\
- EXT4_FEATURE_COMPAT_SPARSE_SUPER2)
+ EXT4_FEATURE_COMPAT_SPARSE_SUPER2|\
+ EXT4_FEATURE_COMPAT_ORPHAN_FILE)
#ifdef CONFIG_MMP
#define EXT4_LIB_INCOMPAT_MMP EXT4_FEATURE_INCOMPAT_MMP
@@ -589,7 +590,8 @@ typedef struct ext2_icount *ext2_icount_t;
EXT4_FEATURE_RO_COMPAT_BIGALLOC|\
EXT4_LIB_RO_COMPAT_QUOTA|\
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM|\
- EXT4_FEATURE_RO_COMPAT_READONLY)
+ EXT4_FEATURE_RO_COMPAT_READONLY|\
+ EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT)
/*
* These features are only allowed if EXT2_FLAG_SOFTSUPP_FEATURES is passed
@@ -1512,6 +1514,13 @@ errcode_t ext2fs_get_data_io(ext2_filsys fs, io_channel *old_io);
errcode_t ext2fs_set_data_io(ext2_filsys fs, io_channel new_io);
errcode_t ext2fs_rewrite_to_io(ext2_filsys fs, io_channel new_io);
+/* orphan.c */
+extern errcode_t ext2fs_create_orphan_file(ext2_filsys fs, blk_t num_blocks);
+extern errcode_t ext2fs_truncate_orphan_file(ext2_filsys fs);
+extern e2_blkcnt_t ext2fs_default_orphan_file_blocks(__u64 num_blocks);
+extern errcode_t ext2fs_orphan_file_block_csum_set(ext2_filsys fs, char *buf);
+extern int ext2fs_orphan_file_block_csum_verify(ext2_filsys fs, char *buf);
+
/* get_pathname.c */
extern errcode_t ext2fs_get_pathname(ext2_filsys fs, ext2_ino_t dir, ext2_ino_t ino,
char **name);
@@ -1645,6 +1654,9 @@ extern int ext2fs_dirent_name_len(const struct ext2_dir_entry *entry);
extern void ext2fs_dirent_set_name_len(struct ext2_dir_entry *entry, int len);
extern int ext2fs_dirent_file_type(const struct ext2_dir_entry *entry);
extern void ext2fs_dirent_set_file_type(struct ext2_dir_entry *entry, int type);
+extern int ext2fs_inodes_per_orphan_block(ext2_filsys fs);
+extern struct ext4_orphan_block_tail *ext2fs_orphan_block_tail(ext2_filsys fs,
+ char *buf)
#endif
@@ -1915,6 +1927,19 @@ _INLINE_ void ext2fs_dirent_set_file_type(struct ext2_dir_entry *entry, int type
entry->name_len = (entry->name_len & 0xff) | (type << 8);
}
+_INLINE_ int ext2fs_inodes_per_orphan_block(ext2_filsys fs)
+{
+ return (fs->blocksize - sizeof(struct ext4_orphan_block_tail)) /
+ sizeof(__u32);
+}
+
+_INLINE_ struct ext4_orphan_block_tail *
+ext2fs_orphan_block_tail(ext2_filsys fs, char *buf)
+{
+ return (struct ext4_orphan_block_tail *)(buf + fs->blocksize -
+ sizeof(struct ext4_orphan_block_tail));
+}
+
#undef _INLINE_
#endif
diff --git a/lib/ext2fs/orphan.c b/lib/ext2fs/orphan.c
new file mode 100644
index 000000000000..d9e5e4e12ae6
--- /dev/null
+++ b/lib/ext2fs/orphan.c
@@ -0,0 +1,227 @@
+/*
+ * orphan.c --- utility function to handle orphan file
+ *
+ * Copyright (C) 2015 Jan Kara.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#include <string.h>
+
+#include "ext2_fs.h"
+#include "ext2fsP.h"
+
+errcode_t ext2fs_truncate_orphan_file(ext2_filsys fs)
+{
+ struct ext2_inode inode;
+ errcode_t err;
+
+ err = ext2fs_read_inode(fs, EXT4_ORPHAN_INO, &inode);
+ if (err)
+ return err;
+
+ err = ext2fs_punch(fs, EXT4_ORPHAN_INO, &inode, NULL, 0, ~0ULL);
+ if (err)
+ return err;
+
+ fs->flags &= ~EXT2_FLAG_SUPER_ONLY;
+ memset(&inode, 0, sizeof(struct ext2_inode));
+ err = ext2fs_write_inode(fs, EXT4_ORPHAN_INO, &inode);
+
+ fs->super->s_feature_compat &= ~EXT4_FEATURE_COMPAT_ORPHAN_FILE;
+ fs->super->s_feature_ro_compat &=
+ ~EXT4_FEATURE_RO_COMPAT_ORPHAN_PRESENT;
+ ext2fs_mark_super_dirty(fs);
+ /* Need to update group descriptors as well */
+ fs->flags &= ~EXT2_FLAG_SUPER_ONLY;
+
+ return err;
+}
+
+struct mkorphan_info {
+ char *buf;
+ char *zerobuf;
+ blk_t num_blocks;
+ blk_t alloc_blocks;
+ errcode_t err;
+};
+
+static int mkorphan_proc(ext2_filsys fs,
+ blk64_t *blocknr,
+ e2_blkcnt_t blockcnt,
+ blk64_t ref_block EXT2FS_ATTR((unused)),
+ int ref_offset EXT2FS_ATTR((unused)),
+ void *priv_data)
+{
+ struct mkorphan_info *oi = (struct mkorphan_info *)priv_data;
+ blk64_t new_blk;
+ errcode_t err;
+
+ err = ext2fs_new_block2(fs, 0, 0, &new_blk);
+ if (err) {
+ oi->err = err;
+ return BLOCK_ABORT;
+ }
+ ext2fs_block_alloc_stats2(fs, new_blk, +1);
+ if (blockcnt >= 0)
+ err = io_channel_write_blk64(fs->io, new_blk, 1, oi->buf);
+ else
+ err = io_channel_write_blk64(fs->io, new_blk, 1, oi->zerobuf);
+ if (err) {
+ oi->err = err;
+ return BLOCK_ABORT;
+ }
+ oi->alloc_blocks++;
+ *blocknr = new_blk;
+ if (blockcnt >= 0 && --oi->num_blocks == 0)
+ return BLOCK_CHANGED | BLOCK_ABORT;
+ return BLOCK_CHANGED;
+}
+
+errcode_t ext2fs_create_orphan_file(ext2_filsys fs, blk_t num_blocks)
+{
+ struct ext2_inode inode;
+ errcode_t err;
+ char *buf = NULL, *zerobuf = NULL;
+ struct mkorphan_info oi;
+ struct ext4_orphan_block_tail *ob_tail;
+
+ err = ext2fs_read_inode(fs, EXT4_ORPHAN_INO, &inode);
+ if (err)
+ return err;
+ if (EXT2_I_SIZE(&inode)) {
+ err = ext2fs_truncate_orphan_file(fs);
+ if (err)
+ return err;
+ }
+
+ memset(&inode, 0, sizeof(struct ext2_inode));
+ if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS) {
+ inode.i_flags |= EXT4_EXTENTS_FL;
+ err = ext2fs_write_inode(fs, EXT4_ORPHAN_INO, &inode);
+ if (err)
+ return err;
+ }
+
+ err = ext2fs_get_mem(fs->blocksize, &buf);
+ if (err)
+ return err;
+ err = ext2fs_get_mem(fs->blocksize, &zerobuf);
+ if (err)
+ goto out;
+ memset(buf, 0, fs->blocksize);
+ memset(zerobuf, 0, fs->blocksize);
+ ob_tail = ext2fs_orphan_block_tail(fs, buf);
+ ob_tail->ob_magic = ext2fs_cpu_to_le32(EXT4_ORPHAN_BLOCK_MAGIC);
+ ext2fs_orphan_file_block_csum_set(fs, buf);
+ oi.num_blocks = num_blocks;
+ oi.alloc_blocks = 0;
+ oi.buf = buf;
+ oi.zerobuf = zerobuf;
+ oi.err = 0;
+ err = ext2fs_block_iterate3(fs, EXT4_ORPHAN_INO, BLOCK_FLAG_APPEND,
+ 0, mkorphan_proc, &oi);
+ if (err)
+ goto out;
+ if (oi.err) {
+ err = oi.err;
+ goto out;
+ }
+
+ /* Reread inode after blocks were allocated */
+ err = ext2fs_read_inode(fs, EXT4_ORPHAN_INO, &inode);
+ if (err)
+ goto out;
+ ext2fs_iblk_set(fs, &inode, 0);
+ inode.i_atime = inode.i_mtime =
+ inode.i_ctime = fs->now ? fs->now : time(0);
+ inode.i_links_count = 1;
+ inode.i_mode = LINUX_S_IFREG | 0600;
+ ext2fs_iblk_add_blocks(fs, &inode, oi.alloc_blocks);
+ err = ext2fs_inode_size_set(fs, &inode,
+ (unsigned long long)fs->blocksize * num_blocks);
+ if (err)
+ goto out;
+ err = ext2fs_write_new_inode(fs, EXT4_ORPHAN_INO, &inode);
+ if (err)
+ goto out;
+
+ fs->super->s_feature_compat |= EXT4_FEATURE_COMPAT_ORPHAN_FILE;
+ ext2fs_mark_super_dirty(fs);
+ /* Need to update group descriptors as well */
+ fs->flags &= ~EXT2_FLAG_SUPER_ONLY;
+out:
+ if (buf)
+ ext2fs_free_mem(&buf);
+ if (zerobuf)
+ ext2fs_free_mem(&zerobuf);
+ return err;
+}
+
+/*
+ * Find reasonable size for orphan file. We choose orphan file size to be
+ * between 32 and 512 filesystem blocks and not more than 1/4096 of the
+ * filesystem unless it is really small.
+ */
+e2_blkcnt_t ext2fs_default_orphan_file_blocks(__u64 num_blocks)
+{
+ if (num_blocks < 128 * 1024)
+ return 32;
+ if (num_blocks < 2 * 1024 * 1024)
+ return num_blocks / 4096;
+ return 512;
+}
+
+static errcode_t ext2fs_orphan_file_block_csum(ext2_filsys fs, char *buf,
+ __u32 *crc)
+{
+ int inodes_per_ob = ext2fs_inodes_per_orphan_block(fs);
+ __u32 gen;
+ ext2_ino_t inum;
+ struct ext2_inode inode;
+ errcode_t retval;
+
+ retval = ext2fs_read_inode(fs, EXT4_ORPHAN_INO, &inode);
+ if (retval)
+ return retval;
+ inum = ext2fs_cpu_to_le32(EXT4_ORPHAN_INO);
+ gen = ext2fs_cpu_to_le32(inode.i_generation);
+ *crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)&inum,
+ sizeof(inum));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)&gen, sizeof(gen));
+ *crc = ext2fs_crc32c_le(*crc, buf, inodes_per_ob * sizeof(__u32));
+
+ return 0;
+}
+
+errcode_t ext2fs_orphan_file_block_csum_set(ext2_filsys fs, char *buf)
+{
+ struct ext4_orphan_block_tail *tail;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ tail = ext2fs_orphan_block_tail(fs, buf);
+ return ext2fs_orphan_file_block_csum(fs, buf, &tail->ob_checksum);
+}
+
+int ext2fs_orphan_file_block_csum_verify(ext2_filsys fs, char *buf)
+{
+ struct ext4_orphan_block_tail *tail;
+ __u32 crc;
+ errcode_t retval;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+ retval = ext2fs_orphan_file_block_csum(fs, buf, &crc);
+ if (retval)
+ return 0;
+ tail = ext2fs_orphan_block_tail(fs, buf);
+ return ext2fs_le32_to_cpu(tail->ob_checksum) == crc;
+}
--
2.1.4
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