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Date: Sun, 16 Sep 2007 22:57:41 -0400
From: Theodore Ts'o <tytso@....edu>
To: linux-ext4@...r.kernel.org
Cc: Theodore Ts'o <tytso@....edu>
Subject: [PATCH,RFC 4/4] Initial checkin for new extents API
Initial implemenation of extents support for e2fsprogs. This is enough
so that e2fsck will pass a valid filesystem containing extents.
Eventually this will be split into a patch for the library changes, and
a separate patch for e2fsck, followed by test cases for e2fsprogs.
---
e2fsck/message.c | 2 +
e2fsck/pass1.c | 86 ++++++-
e2fsck/problem.c | 5 +
e2fsck/problem.h | 3 +
lib/ext2fs/Makefile.in | 68 +++++-
lib/ext2fs/ext2_err.et.in | 40 +++-
lib/ext2fs/ext2fs.h | 62 +++++-
lib/ext2fs/ext3_extents.h | 20 ++
lib/ext2fs/extent.c | 616 +++++++++++++++++++++++++++++++++++++++++++++
lib/ext2fs/extent_dbg.ct | 32 +++
10 files changed, 926 insertions(+), 8 deletions(-)
create mode 100644 lib/ext2fs/extent.c
create mode 100644 lib/ext2fs/extent_dbg.ct
diff --git a/e2fsck/message.c b/e2fsck/message.c
index b2e3e0f..accf3a0 100644
--- a/e2fsck/message.c
+++ b/e2fsck/message.c
@@ -80,6 +80,7 @@
* @S superblock
* @u unattached
* @v device
+ * @x extent
* @z zero-length
*/
@@ -134,6 +135,7 @@ static const char *abbrevs[] = {
N_("Ssuper@b"),
N_("uunattached"),
N_("vdevice"),
+ N_("xextent"),
N_("zzero-length"),
"@@",
0
diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index 7fba823..f9b7ea3 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -908,10 +908,11 @@ void e2fsck_pass1(e2fsck_t ctx)
ctx->fs_dind_count++;
if (inode->i_block[EXT2_TIND_BLOCK])
ctx->fs_tind_count++;
- if (inode->i_block[EXT2_IND_BLOCK] ||
- inode->i_block[EXT2_DIND_BLOCK] ||
- inode->i_block[EXT2_TIND_BLOCK] ||
- inode->i_file_acl) {
+ if (!(inode->i_flags & EXT4_EXTENTS_FL) &&
+ (inode->i_block[EXT2_IND_BLOCK] ||
+ inode->i_block[EXT2_DIND_BLOCK] ||
+ inode->i_block[EXT2_TIND_BLOCK] ||
+ inode->i_file_acl)) {
inodes_to_process[process_inode_count].ino = ino;
inodes_to_process[process_inode_count].inode = *inode;
process_inode_count++;
@@ -1488,6 +1489,78 @@ void e2fsck_clear_inode(e2fsck_t ctx, ext2_ino_t ino,
e2fsck_write_inode(ctx, ino, inode, source);
}
+static void scan_extent_node(e2fsck_t ctx, struct problem_context *pctx,
+ ext2_extent_handle_t ehandle)
+{
+ struct ext2fs_extent extent;
+ blk_t blk;
+ e2_blkcnt_t blockcnt;
+ int i;
+ int is_dir, is_leaf;
+
+
+ pctx->errcode = ext2fs_extent_get(ehandle, EXT2_EXTENT_FIRST_SIB,
+ &extent);
+ while (!pctx->errcode) {
+ is_leaf = extent.e_flags & EXT2_EXTENT_FLAGS_LEAF;
+ is_dir = LINUX_S_ISDIR(pctx->inode->i_mode);
+
+ if (!is_leaf) {
+ mark_block_used(ctx, extent.e_pblk);
+ pctx->errcode = ext2fs_extent_get(ehandle,
+ EXT2_EXTENT_DOWN, &extent);
+ scan_extent_node(ctx, pctx, ehandle);
+ pctx->errcode = ext2fs_extent_get(ehandle,
+ EXT2_EXTENT_UP, &extent);
+ goto next;
+ }
+
+ for (blk = extent.e_pblk, blockcnt = extent.e_lblk, i = 0;
+ i < extent.e_len;
+ blk++, blockcnt++, i++) {
+ mark_block_used(ctx, blk);
+
+ if (is_dir) {
+ pctx->errcode = ext2fs_add_dir_block(ctx->fs->dblist, pctx->ino, blk, blockcnt);
+ if (pctx->errcode) {
+ pctx->blk = blk;
+ pctx->num = blockcnt;
+ fix_problem(ctx, PR_1_ADD_DBLOCK, pctx);
+ /* Should never get here */
+ ctx->flags |= E2F_FLAG_ABORT;
+ return;
+ }
+ }
+ }
+ next:
+ pctx->errcode = ext2fs_extent_get(ehandle,
+ EXT2_EXTENT_NEXT_SIB,
+ &extent);
+ }
+}
+
+
+static void check_blocks_extents(e2fsck_t ctx, struct problem_context *pctx,
+ char *block_buf)
+{
+ struct ext2_inode *inode = pctx->inode;
+ ext2_extent_handle_t ehandle;
+ ext2_filsys fs = ctx->fs;
+ ext2_ino_t ino = pctx->ino;
+
+ pctx->errcode = ext2fs_extent_open(fs, ino, &ehandle);
+ if (pctx->errcode &&
+ fix_problem(ctx, PR_1_READ_EXTENT, pctx)) {
+ e2fsck_clear_inode(ctx, ino, inode, 0, "check_blocks_extents");
+ return;
+ }
+
+ scan_extent_node(ctx, pctx, ehandle);
+
+ ext2fs_extent_free(ehandle);
+
+}
+
/*
* This subroutine is called on each inode to account for all of the
* blocks used by that inode.
@@ -1503,6 +1576,11 @@ static void check_blocks(e2fsck_t ctx, struct problem_context *pctx,
int dirty_inode = 0;
__u64 size;
+ if (inode->i_flags & EXT4_EXTENTS_FL) {
+ check_blocks_extents(ctx, pctx, block_buf);
+ return;
+ }
+
pb.ino = ino;
pb.num_blocks = 0;
pb.last_block = -1;
diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index 0b6fd39..8c8be7e 100644
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c
@@ -784,6 +784,11 @@ static struct e2fsck_problem problem_table[] = {
N_("@i %i is a %It but it looks like it is really a directory.\n"),
PROMPT_FIX, 0 },
+ /* Error while reading extent tree */
+ { PR_1_READ_EXTENT,
+ N_("Error while reading over @x tree in @i %i: %m\n"),
+ PROMPT_CLEAR_INODE, 0 },
+
/* Pass 1b errors */
/* Pass 1B: Rescan for duplicate/bad blocks */
diff --git a/e2fsck/problem.h b/e2fsck/problem.h
index f5f7212..538dee2 100644
--- a/e2fsck/problem.h
+++ b/e2fsck/problem.h
@@ -455,6 +455,9 @@ struct problem_context {
/* inode appears to be a directory */
#define PR_1_TREAT_AS_DIRECTORY 0x010055
+/* Error while reading extent tree */
+#define PR_1_READ_EXTENT 0x010056
+
/*
* Pass 1b errors
*/
diff --git a/lib/ext2fs/Makefile.in b/lib/ext2fs/Makefile.in
index 03ce131..f3edbf7 100644
--- a/lib/ext2fs/Makefile.in
+++ b/lib/ext2fs/Makefile.in
@@ -10,6 +10,8 @@ INSTALL = @INSTALL@
@DEBUGFS_CMT@...UGFS_LIB_OBJS = bb_compat.o fileio.o \
@DEBUGFS_CMT@ inode_io.o namei.o write_bb_file.o
+MK_CMDS= _SS_DIR_OVERRIDE=../ss ../ss/mk_cmds
+
@RESIZER_CMT@...IZE_LIB_OBJS = dupfs.o test_io.o
@IMAGER_CMT@...MAGE_LIB_OBJS = imager.o
@@ -35,6 +37,7 @@ OBJS= $(DEBUGFS_LIB_OBJS) $(RESIZE_LIB_OBJS) $(E2IMAGE_LIB_OBJS) \
dir_iterate.o \
expanddir.o \
ext_attr.o \
+ extent.o \
finddev.o \
flushb.o \
freefs.o \
@@ -90,6 +93,7 @@ SRCS= ext2_err.c \
$(srcdir)/dupfs.c \
$(srcdir)/expanddir.c \
$(srcdir)/ext_attr.c \
+ $(srcdir)/extent.c \
$(srcdir)/fileio.c \
$(srcdir)/finddev.c \
$(srcdir)/flushb.c \
@@ -239,6 +243,68 @@ ext2_tdbtool: tdbtool.o
@echo " LD $@"
@$(CC) -o ext2_tdbtool tdbtool.o tdb.o
+extent_dbg.c: $(srcdir)/extent_dbg.ct
+ @echo " MK_CMDS $<"
+ @$(MK_CMDS) $(srcdir)/extent_dbg.ct
+
+debug_cmds.c debug_cmds.h: $(top_srcdir)/debugfs/debug_cmds.ct
+ @echo " MK_CMDS $<@"
+ @$(MK_CMDS) $(top_srcdir)/debugfs/debug_cmds.ct
+
+DEBUG_OBJS= debug_cmds.o debugfs.o util.o ncheck.o icheck.o ls.o \
+ lsdel.o dump.o set_fields.o logdump.o htree.o unused.o
+
+debugfs.o: $(top_srcdir)/debugfs/debugfs.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+util.o: $(top_srcdir)/debugfs/util.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+ncheck.o: $(top_srcdir)/debugfs/ncheck.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+icheck.o: $(top_srcdir)/debugfs/icheck.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+ls.o: $(top_srcdir)/debugfs/ls.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+lsdel.o: $(top_srcdir)/debugfs/lsdel.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+dump.o: $(top_srcdir)/debugfs/dump.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+set_fields.o: $(top_srcdir)/debugfs/set_fields.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+logdump.o: $(top_srcdir)/debugfs/logdump.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+htree.o: $(top_srcdir)/debugfs/htree.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+unused.o: $(top_srcdir)/debugfs/unused.c
+ @echo " CC $<"
+ @$(CC) $(ALL_CFLAGS) -c $< -o $@
+
+tst_extents: $(srcdir)/extent.c extent_dbg.c $(DEBUG_OBJS) $(LIBSS) $(LIBE2P) $(DEPLIBUUID) $(DEPLIBBLKID)
+ @echo " LD $@"
+ @$(CC) -o tst_extents $(srcdir)/extent.c extent_dbg.c \
+ $(ALL_CFLAGS) -DDEBUG $(DEBUG_OBJS) $(LIBSS) $(LIBE2P) \
+ $(LIBUUID) $(STATIC_LIBEXT2FS) $(LIBBLKID) $(LIBCOM_ERR) \
+ -I $(top_srcdir)/debugfs
+
mkjournal: mkjournal.c $(STATIC_LIBEXT2FS)
@echo " LD $@"
@$(CC) -o mkjournal $(srcdir)/mkjournal.c -DDEBUG $(STATIC_LIBEXT2FS) $(LIBCOM_ERR) $(ALL_CFLAGS)
@@ -282,7 +348,7 @@ clean::
tst_badblocks tst_iscan ext2_err.et ext2_err.c ext2_err.h \
tst_byteswap tst_ismounted tst_getsize tst_sectgetsize \
tst_bitops tst_types tst_icount tst_super_size \
- ext2_tdbtool mkjournal \
+ ext2_tdbtool mkjournal debug_cmds.c \
../libext2fs.a ../libext2fs_p.a ../libext2fs_chk.a
mostlyclean:: clean
diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in
index eda4bb4..5d62548 100644
--- a/lib/ext2fs/ext2_err.et.in
+++ b/lib/ext2fs/ext2_err.et.in
@@ -62,8 +62,8 @@ ec EXT2_ET_MAGIC_E2IMAGE,
ec EXT2_ET_MAGIC_INODE_IO_CHANNEL,
"Wrong magic number for inode io_channel structure"
-ec EXT2_ET_MAGIC_RESERVED_9,
- "Wrong magic number --- RESERVED_9"
+ec EXT2_ET_MAGIC_EXTENT_HANDLE,
+ "Wrong magic number for ext4 extent handle"
ec EXT2_ET_BAD_MAGIC,
"Bad magic number in super-block"
@@ -326,5 +326,41 @@ ec EXT2_ET_TDB_ERR_NOEXIST,
ec EXT2_ET_TDB_ERR_RDONLY,
"TDB: Write not permitted"
+ec EXT2_ET_EXTENT_HEADER_BAD,
+ "Corrupt extent header"
+
+ec EXT2_ET_EXTENT_INDEX_BAD,
+ "Corrupt extent index"
+
+ec EXT2_ET_EXTENT_LEAF_BAD,
+ "Corrupt extent"
+
+ec EXT2_ET_EXTENT_NO_SPACE,
+ "No free space in extent map"
+
+ec EXT2_ET_INODE_NOT_EXTENT,
+ "Inode does not use extents"
+
+ec EXT2_ET_EXTENT_NO_NEXT,
+ "No 'next' extent"
+
+ec EXT2_ET_EXTENT_NO_PREV,
+ "No 'previous' extent"
+
+ec EXT2_ET_EXTENT_NO_UP,
+ "No 'up' extent"
+
+ec EXT2_ET_EXTENT_NO_DOWN,
+ "No 'down' extent"
+
+ec EXT2_ET_NO_CURRENT_NODE,
+ "No current node"
+
+ec EXT2_ET_OP_NOT_SUPPORTED,
+ "Ext2fs operation not supported"
+
+ec EXT2_ET_CANT_INSERT_EXTENT,
+ "No room to insert extent in node"
+
end
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 83a9091..022d7f4 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -65,6 +65,7 @@ extern "C" {
typedef __u32 ext2_ino_t;
typedef __u32 blk_t;
+typedef __u64 blk64_t;
typedef __u32 dgrp_t;
typedef __u32 ext2_off_t;
typedef __s64 e2_blkcnt_t;
@@ -285,6 +286,51 @@ struct struct_ext2_filsys {
#endif
/*
+ * Generic (non-filesystem layout specific) extents structure
+ */
+
+#define EXT2_EXTENT_FLAGS_LEAF 0x0001
+#define EXT2_EXTENT_FLAGS_UNINIT 0x0002
+
+struct ext2fs_extent {
+ blk64_t e_pblk; /* first physical block */
+ blk64_t e_lblk; /* first logical block extent covers */
+ __u32 e_len; /* number of blocks covered by extent */
+ __u32 e_flags; /* extent flags */
+};
+
+typedef struct ext2_extent_handle *ext2_extent_handle_t;
+
+/*
+ * Flags used by ext2fs_extent_get()
+ */
+#define EXT2_EXTENT_CURRENT 0x0000
+#define EXT2_EXTENT_MOVE_MASK 0x000F
+#define EXT2_EXTENT_ROOT 0x0001
+#define EXT2_EXTENT_FIRST_SIB 0x0002
+#define EXT2_EXTENT_NEXT_SIB 0x0003
+#define EXT2_EXTENT_PREV_SIB 0x0004
+#define EXT2_EXTENT_UP 0x0005
+#define EXT2_EXTENT_DOWN 0x0006
+#define EXT2_EXTENT_NEXT_LEAF 0x0007
+#define EXT2_EXTENT_PREV_LEAF 0x0008
+
+/*
+ * Data structure returned by ext2fs_extent_get_info()
+ */
+struct ext2_extent_info {
+ int curr_entry;
+ int curr_level;
+ int num_entries;
+ int max_entries;
+ int bytes_avail;
+ blk64_t max_lblk;
+ blk64_t max_pblk;
+ __u32 max_len;
+ __u32 max_uninit_len;
+};
+
+/*
* Flags for directory block reading and writing functions
*/
#define EXT2_DIRBLOCK_V2_STRUCT 0x0001
@@ -437,7 +483,8 @@ typedef struct ext2_icount *ext2_icount_t;
#define EXT2_LIB_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE|\
EXT3_FEATURE_INCOMPAT_JOURNAL_DEV|\
EXT2_FEATURE_INCOMPAT_META_BG|\
- EXT3_FEATURE_INCOMPAT_RECOVER)
+ EXT3_FEATURE_INCOMPAT_RECOVER|\
+ EXT3_FEATURE_INCOMPAT_EXTENTS)
#endif
#define EXT2_LIB_FEATURE_RO_COMPAT_SUPP (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER|\
EXT2_FEATURE_RO_COMPAT_LARGE_FILE)
@@ -715,6 +762,19 @@ extern errcode_t ext2fs_adjust_ea_refcount(ext2_filsys fs, blk_t blk,
char *block_buf,
int adjust, __u32 *newcount);
+/* extent.c */
+extern errcode_t ext2fs_extent_open(ext2_filsys fs, ext2_ino_t ino,
+ ext2_extent_handle_t *handle);
+extern errcode_t ext2fs_extent_get(ext2_extent_handle_t handle,
+ int flags, struct ext2fs_extent *extent);
+extern errcode_t ext2fs_extent_replace(ext2_extent_handle_t handle, int flags,
+ struct ext2fs_extent *extent);
+extern errcode_t ext2fs_extent_insert(ext2_extent_handle_t handle, int flags,
+ struct ext2fs_extent *extent);
+extern errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle, int flags);
+extern errcode_t ext2fs_extent_get_info(ext2_extent_handle_t handle,
+ struct ext2_extent_info *info);
+
/* fileio.c */
extern errcode_t ext2fs_file_open2(ext2_filsys fs, ext2_ino_t ino,
struct ext2_inode *inode,
diff --git a/lib/ext2fs/ext3_extents.h b/lib/ext2fs/ext3_extents.h
index c4178c9..ba980e4 100644
--- a/lib/ext2fs/ext3_extents.h
+++ b/lib/ext2fs/ext3_extents.h
@@ -126,6 +126,26 @@ struct ext3_ext_path {
#define EXT_MAX_BLOCK 0xffffffff
#define EXT_CACHE_MARK 0xffff
+/*
+ * EXT_INIT_MAX_LEN is the maximum number of blocks we can have in an
+ * initialized extent. This is 2^15 and not (2^16 - 1), since we use the
+ * MSB of ee_len field in the extent datastructure to signify if this
+ * particular extent is an initialized extent or an uninitialized (i.e.
+ * preallocated).
+ * EXT_UNINIT_MAX_LEN is the maximum number of blocks we can have in an
+ * uninitialized extent.
+ * If ee_len is <= 0x8000, it is an initialized extent. Otherwise, it is an
+ * uninitialized one. In other words, if MSB of ee_len is set, it is an
+ * uninitialized extent with only one special scenario when ee_len = 0x8000.
+ * In this case we can not have an uninitialized extent of zero length and
+ * thus we make it as a special case of initialized extent with 0x8000 length.
+ * This way we get better extent-to-group alignment for initialized extents.
+ * Hence, the maximum number of blocks we can have in an *initialized*
+ * extent is 2^15 (32768) and in an *uninitialized* extent is 2^15-1 (32767).
+ */
+#define EXT_INIT_MAX_LEN (1UL << 15)
+#define EXT_UNINIT_MAX_LEN (EXT_INIT_MAX_LEN - 1)
+
#define EXT_FIRST_EXTENT(__hdr__) \
((struct ext3_extent *) (((char *) (__hdr__)) + \
diff --git a/lib/ext2fs/extent.c b/lib/ext2fs/extent.c
new file mode 100644
index 0000000..a6f4f65
--- /dev/null
+++ b/lib/ext2fs/extent.c
@@ -0,0 +1,616 @@
+/*
+ * extent.c --- routines to implement extents support
+ *
+ * Copyright (C) 2007 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fsP.h"
+#include "e2image.h"
+#include "ss/ss.h"
+
+/*
+ * Definitions to be dropped in lib/ext2fs/ext2fs.h
+ */
+
+/*
+ * Private definitions
+ */
+
+struct extent_path {
+ char *buf;
+ int entries;
+ int max_entries;
+ int left;
+ blk64_t end_blk;
+ void *curr;
+};
+
+
+struct ext2_extent_handle {
+ errcode_t magic;
+ ext2_filsys fs;
+ ext2_ino_t ino;
+ struct ext2_inode *inode;
+ int type;
+ int level;
+ int max_depth;
+ struct extent_path *path;
+};
+
+/*
+ * Useful Debugging stuff
+ */
+
+#ifdef DEBUG
+#define EXT_DEBUG
+#endif
+
+#ifdef EXT_DEBUG
+static void ext_show_header(struct ext3_extent_header *eh)
+{
+ printf("header: magic=%x entries=%u max=%u depth=%u generation=%u\n",
+ eh->eh_magic, eh->eh_entries, eh->eh_max, eh->eh_depth,
+ eh->eh_generation);
+}
+
+static void ext_show_index(struct ext3_extent_idx *ix)
+{
+ printf("index: block=%u leaf=%u leaf_hi=%u unused=%u\n",
+ ix->ei_block, ix->ei_leaf, ix->ei_leaf_hi, ix->ei_unused);
+}
+
+static void ext_show_extent(struct ext3_extent *ex)
+{
+ printf("extent: block=%u-%u len=%u start=%u start_hi=%u\n",
+ ex->ee_block, ex->ee_block + ex->ee_len - 1,
+ ex->ee_len, ex->ee_start, ex->ee_start_hi);
+}
+
+#define ext_printf(fmt, args...) printf(fmt, ## args)
+#else
+#define ext_show_header(eh) do { } while (0)
+#define ext_show_index(ix) do { } while (0)
+#define ext_show_extent(ex) do { } while (0)
+#define ext_printf(fmt, args...) do { } while (0)
+#endif
+
+/*
+ * Begin functions to handle an inode's extent information
+ */
+
+extern void ext2fs_extent_free(ext2_extent_handle_t handle)
+{
+ int i;
+
+ if (!handle)
+ return;
+
+ if (handle->inode)
+ ext2fs_free_mem(&handle->inode);
+ if (handle->path) {
+ for (i=1; i < handle->max_depth; i++) {
+ if (handle->path[i].buf)
+ ext2fs_free_mem(&handle->path[i].buf);
+ }
+ }
+ ext2fs_free_mem(&handle);
+}
+
+extern errcode_t ext2fs_extent_open(ext2_filsys fs, ext2_ino_t ino,
+ ext2_extent_handle_t *ret_handle)
+{
+ struct ext2_extent_handle *handle;
+ errcode_t retval;
+ int isize = EXT2_INODE_SIZE(fs->super);
+ struct ext3_extent_header *eh;
+ struct ext3_extent_idx *ix;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ if ((ino == 0) || (ino > fs->super->s_inodes_count))
+ return EXT2_ET_BAD_INODE_NUM;
+
+ retval = ext2fs_get_mem(sizeof(struct ext2_extent_handle), &handle);
+ if (retval)
+ return retval;
+ memset(handle, 0, sizeof(struct ext2_extent_handle));
+
+ retval = ext2fs_get_mem(isize, &handle->inode);
+ if (retval)
+ goto errout;
+
+ handle->ino = ino;
+ handle->fs = fs;
+
+ retval = ext2fs_read_inode_full(fs, ino, handle->inode, isize);
+ if (retval)
+ goto errout;
+
+ if (!(handle->inode->i_flags & EXT4_EXTENTS_FL))
+ return EXT2_ET_INODE_NOT_EXTENT;
+
+ eh = (struct ext3_extent_header *) &handle->inode->i_block;
+
+ if (ext2fs_le16_to_cpu(eh->eh_magic) != EXT3_EXT_MAGIC)
+ return EXT2_ET_EXTENT_HEADER_BAD;
+
+ ext_show_header(eh);
+
+ handle->max_depth = ext2fs_le16_to_cpu(eh->eh_depth);
+ handle->type = ext2fs_le16_to_cpu(eh->eh_magic);
+
+ retval = ext2fs_get_mem(((handle->max_depth+1) *
+ sizeof(struct extent_path)),
+ &handle->path);
+ memset(handle->path, 0,
+ (handle->max_depth+1) * sizeof(struct extent_path));
+ handle->path[0].buf = (char *) handle->inode->i_block;
+
+ handle->path[0].left = handle->path[0].entries =
+ ext2fs_le16_to_cpu(eh->eh_entries);
+ handle->path[0].max_entries = ext2fs_le16_to_cpu(eh->eh_max);
+ handle->path[0].curr = 0;
+ handle->path[0].end_blk =
+ ((((__u64) handle->inode->i_size_high << 32) +
+ handle->inode->i_size + (fs->blocksize - 1))
+ >> EXT2_BLOCK_SIZE_BITS(fs->super));
+ handle->level = 0;
+ handle->magic = EXT2_ET_MAGIC_EXTENT_HANDLE;
+
+ *ret_handle = handle;
+ return 0;
+
+errout:
+ ext2fs_extent_free(handle);
+ return retval;
+}
+
+/*
+ * This function is responsible for (optionally) moving through the
+ * extent tree and then returning the current extent
+ */
+errcode_t ext2fs_extent_get(ext2_extent_handle_t handle,
+ int flags, struct ext2fs_extent *extent)
+{
+ struct extent_path *path, *newpath;
+ struct ext3_extent_header *eh;
+ struct ext3_extent_idx *ix = 0;
+ struct ext3_extent *ex;
+ errcode_t retval;
+ blk_t blk;
+ blk64_t end_blk;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
+
+ if (!handle->path)
+ return EXT2_ET_NO_CURRENT_NODE;
+
+ path = handle->path + handle->level;
+ switch (flags & EXT2_EXTENT_MOVE_MASK) {
+ case EXT2_EXTENT_CURRENT:
+ ix = path->curr;
+ break;
+ case EXT2_EXTENT_ROOT:
+ handle->level = 0;
+ case EXT2_EXTENT_FIRST_SIB:
+ path->left = path->entries;
+ path->curr = 0;
+ case EXT2_EXTENT_NEXT_SIB:
+ if (path->curr) {
+ if (path->left <= 0)
+ return EXT2_ET_EXTENT_NO_NEXT;
+ ix = path->curr;
+ ix++;
+ } else {
+ if (path->entries == 0)
+ return EXT2_ET_EXTENT_NO_NEXT;
+ eh = (struct ext3_extent_header *) path->buf;
+ ix = EXT_FIRST_INDEX(eh);
+ }
+ path->left--;
+ path->curr = ix;
+ break;
+ case EXT2_EXTENT_PREV_SIB:
+ if (!path->curr ||
+ path->left+1 >= path->entries)
+ return EXT2_ET_EXTENT_NO_PREV;
+ ix = path->curr;
+ ix--;
+ path->curr = ix;
+ path->left++;
+ break;
+ case EXT2_EXTENT_UP:
+ if (handle->level <= 0)
+ return EXT2_ET_EXTENT_NO_UP;
+ handle->level--;
+ path--;
+ ix = path->curr;
+ break;
+ case EXT2_EXTENT_DOWN:
+ if (!path->curr ||(handle->level >= handle->max_depth))
+ return EXT2_ET_EXTENT_NO_DOWN;
+
+ ix = path->curr;
+ newpath = path + 1;
+ if (!newpath->buf) {
+ retval = ext2fs_get_mem(handle->fs->blocksize,
+ &newpath->buf);
+ if (retval)
+ return retval;
+ }
+ blk = ext2fs_le32_to_cpu(ix->ei_leaf) +
+ ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi));
+ if ((handle->fs->flags & EXT2_FLAG_IMAGE_FILE) &&
+ (handle->fs->io != handle->fs->image_io))
+ memset(newpath->buf, 0, handle->fs->blocksize);
+ else {
+ retval = io_channel_read_blk(handle->fs->io,
+ blk, 1, newpath->buf);
+ if (retval)
+ return retval;
+ }
+ handle->level++;
+
+ eh = (struct ext3_extent_header *) newpath->buf;
+
+ ext_show_header(eh);
+ newpath->left = newpath->entries =
+ ext2fs_le16_to_cpu(eh->eh_entries);
+ newpath->max_entries = ext2fs_le16_to_cpu(eh->eh_max);
+
+ if (path->left > 0) {
+ ix++;
+ newpath->end_blk = ext2fs_le32_to_cpu(ix->ei_block);
+ } else
+ newpath->end_blk = path->end_blk;
+
+ ix = EXT_FIRST_INDEX((struct ext3_extent_header *) eh);
+ newpath->curr = ix;
+ newpath->left = newpath->entries - 1;
+ path = newpath;
+
+ ext_printf("Down to level %d/%d, end_blk=%llu\n",
+ handle->level, handle->max_depth,
+ path->end_blk);
+
+ break;
+ default:
+ return EXT2_ET_OP_NOT_SUPPORTED;
+ }
+
+ if (!ix)
+ return EXT2_ET_NO_CURRENT_NODE;
+
+ ext_printf("Left is now: %d\n", path->left);
+
+ extent->e_flags = 0;
+
+ if (handle->level == handle->max_depth) {
+ ex = (struct ext3_extent *) ix;
+
+ extent->e_pblk = ext2fs_le32_to_cpu(ex->ee_start) +
+ ((__u64) ext2fs_le16_to_cpu(ex->ee_start_hi) << 32);
+ extent->e_lblk = ext2fs_le32_to_cpu(ex->ee_block);
+ extent->e_len = ext2fs_le16_to_cpu(ex->ee_len);
+ extent->e_flags = EXT2_EXTENT_FLAGS_LEAF;
+ if (extent->e_len > EXT_INIT_MAX_LEN) {
+ extent->e_len -= EXT_INIT_MAX_LEN;
+ extent->e_flags = EXT2_EXTENT_FLAGS_UNINIT;
+ }
+ } else {
+ extent->e_pblk = ext2fs_le32_to_cpu(ix->ei_leaf) +
+ ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
+ extent->e_lblk = ext2fs_le32_to_cpu(ix->ei_block);
+ if (path->left > 0) {
+ ix++;
+ end_blk = ext2fs_le32_to_cpu(ix->ei_block);
+ } else
+ end_blk = path->end_blk;
+
+ extent->e_len = end_blk - extent->e_lblk;
+ }
+
+ return 0;
+}
+
+static errcode_t update_path(ext2_extent_handle_t handle)
+{
+ struct extent_path *path;
+ blk64_t blk;
+ errcode_t retval;
+ struct ext3_extent_idx *ix;
+
+ if (handle->level == 0) {
+ retval = ext2fs_write_inode_full(handle->fs, handle->ino,
+ handle->inode, EXT2_INODE_SIZE(handle->fs->super));
+ } else {
+ ix = handle->path[handle->level - 1].curr;
+ blk = ext2fs_le32_to_cpu(ix->ei_leaf) +
+ ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
+
+ retval = io_channel_write_blk(handle->fs->io,
+ blk, 1, handle->path[handle->level].buf);
+ }
+ return retval;
+}
+
+errcode_t ext2fs_extent_replace(ext2_extent_handle_t handle, int flags,
+ struct ext2fs_extent *extent)
+{
+ struct extent_path *path;
+ struct ext3_extent_idx *ix;
+ struct ext3_extent *ex;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
+
+ if (!handle->path)
+ return EXT2_ET_NO_CURRENT_NODE;
+
+ path = handle->path + handle->level;
+ if (!path->curr)
+ return EXT2_ET_NO_CURRENT_NODE;
+
+ if (handle->level == handle->max_depth) {
+ ex = path->curr;
+
+ ex->ee_block = ext2fs_cpu_to_le32(extent->e_lblk);
+ ex->ee_start = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF);
+ ex->ee_start_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32);
+ ex->ee_len = ext2fs_cpu_to_le16(extent->e_len);
+ } else {
+ ix = path->curr;
+
+ ix->ei_leaf = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF);
+ ix->ei_leaf_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32);
+ ix->ei_block = ext2fs_cpu_to_le32(extent->e_lblk);
+ ix->ei_unused = 0;
+ }
+ update_path(handle);
+ return 0;
+}
+
+errcode_t ext2fs_extent_insert(ext2_extent_handle_t handle, int flags,
+ struct ext2fs_extent *extent)
+{
+ struct extent_path *path;
+ struct ext3_extent_idx *ix;
+ struct ext3_extent_header *eh;
+ errcode_t retval;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
+
+ if (!handle->path)
+ return EXT2_ET_NO_CURRENT_NODE;
+
+ path = handle->path + handle->level;
+
+ eh = (struct ext3_extent_header *) path->buf;
+ if (path->curr) {
+ ix = path->curr;
+ ix++;
+ } else
+ path->curr = ix = EXT_FIRST_INDEX(eh);
+
+ if (path->left)
+ memmove(ix, ix + 1,
+ path->left * sizeof(struct ext3_extent_idx));
+ path->left++;
+ path->entries++;
+
+
+ retval = ext2fs_extent_replace(handle, 0, extent);
+ if (retval)
+ goto errout;
+
+ retval = update_path(handle);
+ if (retval)
+ goto errout;
+
+ return 0;
+
+errout:
+ ext2fs_extent_delete(handle, 0);
+ return retval;
+}
+
+errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle, int flags)
+{
+ struct extent_path *path;
+ char *cp;
+ struct ext3_extent_header *eh;
+ errcode_t retval;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
+
+ if (!handle->path)
+ return EXT2_ET_NO_CURRENT_NODE;
+
+ path = handle->path + handle->level;
+ if (!path->curr)
+ return EXT2_ET_NO_CURRENT_NODE;
+
+ cp = path->curr;
+
+ if (path->left) {
+ memmove(cp, cp + sizeof(struct ext3_extent_idx),
+ path->left * sizeof(struct ext3_extent_idx));
+ path->left--;
+ }
+ path->entries--;
+ if (path->entries == 0)
+ path->curr = 0;
+
+ eh = (struct ext3_extent_header *) path->buf;
+ eh->eh_entries = ext2fs_cpu_to_le16(path->entries);
+
+ retval = update_path(handle);
+
+ return retval;
+}
+
+errcode_t ext2fs_extent_get_info(ext2_extent_handle_t handle,
+ struct ext2_extent_info *info)
+{
+ struct extent_path *path;
+ struct ext3_extent_idx *ix;
+ struct ext3_extent *ex;
+
+ EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
+
+ memset(info, 0, sizeof(struct ext2_extent_info));
+
+ path = handle->path + handle->level;
+ if (path) {
+ if (path->curr)
+ info->curr_entry = ((char *) path->curr - path->buf) /
+ sizeof(struct ext3_extent_idx);
+ else
+ info->curr_entry = 0;
+ info->num_entries = path->entries;
+ info->max_entries = path->max_entries;
+ info->bytes_avail = path->max_entries - path->entries;
+ }
+
+ info->max_lblk = ((__u64) 1 << 32) - 1;
+ info->max_pblk = ((__u64) 1 << 48) - 1;
+ info->max_len = (1UL << 15);
+ info->max_uninit_len = (1UL << 15) - 1;
+
+ return 0;
+}
+
+
+
+#ifdef DEBUG
+
+#include "debugfs.h"
+
+/*
+ * Hook in new commands into debugfs
+ */
+char *debug_prog_name = "tst_extents";
+extern ss_request_table extent_cmds;
+ss_request_table *extra_cmds = &extent_cmds;
+
+ext2_ino_t current_ino = 0;
+ext2_extent_handle_t current_handle;
+
+void do_inode(int argc, char *argv[])
+{
+ ext2_ino_t inode;
+ int i;
+ struct ext3_extent_header *eh;
+ errcode_t retval;
+
+ if (check_fs_open(argv[0]))
+ return;
+
+ if (argc == 1) {
+ if (current_ino)
+ printf("Current inode is %d\n", current_ino);
+ else
+ printf("No current inode\n");
+ return;
+ }
+
+ if (common_inode_args_process(argc, argv, &inode, 0)) {
+ return;
+ }
+
+ current_ino = 0;
+
+ retval = ext2fs_extent_open(current_fs, inode, ¤t_handle);
+ if (retval) {
+ com_err(argv[1], retval, "while opening extent handle");
+ return;
+ }
+
+ current_ino = inode;
+
+ printf("Loaded inode %d\n", current_ino);
+
+ return;
+}
+
+void generic_goto_node(char *cmd_name, int op)
+{
+ struct ext2fs_extent extent;
+ errcode_t retval;
+
+ if (check_fs_open(cmd_name))
+ return;
+
+ retval = ext2fs_extent_get(current_handle, op, &extent);
+ if (retval) {
+ com_err(cmd_name, retval, 0);
+ return;
+ }
+ printf("Extent: lblk %llu, len %lu, pblk %llu, flags: ",
+ extent.e_lblk, extent.e_len, extent.e_pblk);
+ if (extent.e_flags & EXT2_EXTENT_FLAGS_LEAF)
+ fputs("LEAF ", stdout);
+ if (extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
+ fputs("UNINIT ", stdout);
+ if (!extent.e_flags)
+ fputs("(none)", stdout);
+ fputc('\n', stdout);
+}
+
+
+void do_current_node(int argc, char *argv[])
+{
+ generic_goto_node(argv[0], EXT2_EXTENT_CURRENT);
+}
+
+void do_root_node(int argc, char *argv[])
+{
+ generic_goto_node(argv[0], EXT2_EXTENT_ROOT);
+}
+
+void do_first_sib(int argc, char *argv[])
+{
+ generic_goto_node(argv[0], EXT2_EXTENT_FIRST_SIB);
+}
+
+void do_next_sib(int argc, char *argv[])
+{
+ generic_goto_node(argv[0], EXT2_EXTENT_NEXT_SIB);
+}
+
+void do_prev_sib(int argc, char *argv[])
+{
+ generic_goto_node(argv[0], EXT2_EXTENT_PREV_SIB);
+}
+
+void do_up(int argc, char *argv[])
+{
+ generic_goto_node(argv[0], EXT2_EXTENT_UP);
+}
+
+void do_down(int argc, char *argv[])
+{
+ generic_goto_node(argv[0], EXT2_EXTENT_DOWN);
+}
+
+#endif
diff --git a/lib/ext2fs/extent_dbg.ct b/lib/ext2fs/extent_dbg.ct
new file mode 100644
index 0000000..21ece39
--- /dev/null
+++ b/lib/ext2fs/extent_dbg.ct
@@ -0,0 +1,32 @@
+#
+# Copyright (C) 1993 Theodore Ts'o. This file may be redistributed
+# under the terms of the GNU Public License.
+#
+command_table extent_cmds;
+
+request do_inode, "Open an inode",
+ inode;
+
+request do_current_node, "Current extent node",
+ current_node, current;
+
+request do_root_node, "Goto root extent",
+ root_node, root;
+
+request do_first_sib, "First sibling",
+ first_sibling, first_sib;
+
+request do_next_sib, "Next sibling",
+ next_sibling, next_sib, next;
+
+request do_prev_sib, "Previous sibling",
+ prev_sibling, prev_sib, prev;
+
+request do_up, "Up node",
+ up_node, up;
+
+request do_down, "Down node",
+ down_node, down;
+
+end;
+
--
1.5.3.1.19.gb5ef6
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