Adding upstream version 1.47.0.upstream/1.47.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 499 insertions, 0 deletions

diff --git a/lib/ext2fs/bmap.c b/lib/ext2fs/bmap.c
new file mode 100644
index 0000000..65c45c5
--- /dev/null
+++ b/lib/ext2fs/bmap.c
@@ -0,0 +1,499 @@
+/*
+ * bmap.c --- logical to physical block mapping
+ *
+ * Copyright (C) 1997 Theodore Ts'o.
+ *
+ * %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 <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <errno.h>
+
+#include "ext2_fs.h"
+#include "ext2fsP.h"
+
+#if defined(__GNUC__) && !defined(NO_INLINE_FUNCS)
+#define _BMAP_INLINE_	__inline__
+#else
+#define _BMAP_INLINE_
+#endif
+
+extern errcode_t ext2fs_bmap(ext2_filsys fs, ext2_ino_t ino,
+			     struct ext2_inode *inode,
+			     char *block_buf, int bmap_flags,
+			     blk_t block, blk_t *phys_blk);
+
+#define inode_bmap(inode, nr) ((inode)->i_block[(nr)])
+
+static _BMAP_INLINE_ errcode_t block_ind_bmap(ext2_filsys fs, int flags,
+					      blk_t ind, char *block_buf,
+					      int *blocks_alloc,
+					      blk_t nr, blk_t *ret_blk)
+{
+	errcode_t	retval;
+	blk_t		b;
+
+	if (!ind) {
+		if (flags & BMAP_SET)
+			return EXT2_ET_SET_BMAP_NO_IND;
+		*ret_blk = 0;
+		return 0;
+	}
+	retval = io_channel_read_blk(fs->io, ind, 1, block_buf);
+	if (retval)
+		return retval;
+
+	if (flags & BMAP_SET) {
+		b = *ret_blk;
+#ifdef WORDS_BIGENDIAN
+		b = ext2fs_swab32(b);
+#endif
+		((blk_t *) block_buf)[nr] = b;
+		return io_channel_write_blk(fs->io, ind, 1, block_buf);
+	}
+
+	b = ((blk_t *) block_buf)[nr];
+
+#ifdef WORDS_BIGENDIAN
+	b = ext2fs_swab32(b);
+#endif
+
+	if (!b && (flags & BMAP_ALLOC)) {
+		b = nr ? ext2fs_le32_to_cpu(((blk_t *)block_buf)[nr - 1]) : ind;
+		retval = ext2fs_alloc_block(fs, b,
+					    block_buf + fs->blocksize, &b);
+		if (retval)
+			return retval;
+
+#ifdef WORDS_BIGENDIAN
+		((blk_t *) block_buf)[nr] = ext2fs_swab32(b);
+#else
+		((blk_t *) block_buf)[nr] = b;
+#endif
+
+		retval = io_channel_write_blk(fs->io, ind, 1, block_buf);
+		if (retval)
+			return retval;
+
+		(*blocks_alloc)++;
+	}
+
+	*ret_blk = b;
+	return 0;
+}
+
+static _BMAP_INLINE_ errcode_t block_dind_bmap(ext2_filsys fs, int flags,
+					       blk_t dind, char *block_buf,
+					       int *blocks_alloc,
+					       blk_t nr, blk_t *ret_blk)
+{
+	blk_t		b = 0;
+	errcode_t	retval;
+	blk_t		addr_per_block;
+
+	addr_per_block = (blk_t) fs->blocksize >> 2;
+
+	retval = block_ind_bmap(fs, flags & ~BMAP_SET, dind, block_buf,
+				blocks_alloc, nr / addr_per_block, &b);
+	if (retval)
+		return retval;
+	retval = block_ind_bmap(fs, flags, b, block_buf, blocks_alloc,
+				nr % addr_per_block, ret_blk);
+	return retval;
+}
+
+static _BMAP_INLINE_ errcode_t block_tind_bmap(ext2_filsys fs, int flags,
+					       blk_t tind, char *block_buf,
+					       int *blocks_alloc,
+					       blk_t nr, blk_t *ret_blk)
+{
+	blk_t		b = 0;
+	errcode_t	retval;
+	blk_t		addr_per_block;
+
+	addr_per_block = (blk_t) fs->blocksize >> 2;
+
+	retval = block_dind_bmap(fs, flags & ~BMAP_SET, tind, block_buf,
+				 blocks_alloc, nr / addr_per_block, &b);
+	if (retval)
+		return retval;
+	retval = block_ind_bmap(fs, flags, b, block_buf, blocks_alloc,
+				nr % addr_per_block, ret_blk);
+	return retval;
+}
+
+static errcode_t extent_bmap(ext2_filsys fs, ext2_ino_t ino,
+			     struct ext2_inode *inode,
+			     ext2_extent_handle_t handle,
+			     char *block_buf, int bmap_flags, blk64_t block,
+			     int *ret_flags, int *blocks_alloc,
+			     blk64_t *phys_blk);
+
+static errcode_t implied_cluster_alloc(ext2_filsys fs, ext2_ino_t ino,
+				       struct ext2_inode *inode,
+				       ext2_extent_handle_t handle,
+				       blk64_t lblk, blk64_t *phys_blk)
+{
+	blk64_t	base_block, pblock = 0;
+	int i;
+
+	if (!ext2fs_has_feature_bigalloc(fs->super))
+		return 0;
+
+	base_block = lblk & ~EXT2FS_CLUSTER_MASK(fs);
+	/*
+	 * Except for the logical block (lblk) that was passed in, search all
+	 * blocks in this logical cluster for a mapping to a physical cluster.
+	 * If any such map exists, calculate the physical block that maps to
+	 * the logical block and return that.
+	 *
+	 * The old code wouldn't even look if (block % cluster_ratio) == 0;
+	 * this is incorrect if we're allocating blocks in reverse order.
+	 */
+	for (i = 0; i < EXT2FS_CLUSTER_RATIO(fs); i++) {
+		if (base_block + i == lblk)
+			continue;
+		extent_bmap(fs, ino, inode, handle, 0, 0,
+			    base_block + i, 0, 0, &pblock);
+		if (pblock)
+			break;
+	}
+	if (pblock == 0)
+		return 0;
+	*phys_blk = pblock - i + (lblk - base_block);
+	return 0;
+}
+
+/* Try to map a logical block to an already-allocated physical cluster. */
+errcode_t ext2fs_map_cluster_block(ext2_filsys fs, ext2_ino_t ino,
+				   struct ext2_inode *inode, blk64_t lblk,
+				   blk64_t *pblk)
+{
+	ext2_extent_handle_t handle;
+	errcode_t retval;
+
+	/* Need bigalloc and extents to be enabled */
+	*pblk = 0;
+	if (!ext2fs_has_feature_bigalloc(fs->super) ||
+	    !(inode->i_flags & EXT4_EXTENTS_FL))
+		return 0;
+
+	retval = ext2fs_extent_open2(fs, ino, inode, &handle);
+	if (retval)
+		goto out;
+
+	retval = implied_cluster_alloc(fs, ino, inode, handle, lblk, pblk);
+	if (retval)
+		goto out2;
+
+out2:
+	ext2fs_extent_free(handle);
+out:
+	return retval;
+}
+
+static errcode_t extent_bmap(ext2_filsys fs, ext2_ino_t ino,
+			     struct ext2_inode *inode,
+			     ext2_extent_handle_t handle,
+			     char *block_buf, int bmap_flags, blk64_t block,
+			     int *ret_flags, int *blocks_alloc,
+			     blk64_t *phys_blk)
+{
+	struct blk_alloc_ctx	alloc_ctx;
+	struct ext2fs_extent	extent;
+	unsigned int		offset;
+	errcode_t		retval = 0;
+	blk64_t			blk64 = 0;
+	int			alloc = 0;
+	int			set_flags;
+
+	set_flags = bmap_flags & BMAP_UNINIT ? EXT2_EXTENT_SET_BMAP_UNINIT : 0;
+
+	if (bmap_flags & BMAP_SET) {
+		retval = ext2fs_extent_set_bmap(handle, block,
+						*phys_blk, set_flags);
+		return retval;
+	}
+	retval = ext2fs_extent_goto(handle, block);
+	if (retval) {
+		/* If the extent is not found, return phys_blk = 0 */
+		if (retval == EXT2_ET_EXTENT_NOT_FOUND) {
+			extent.e_lblk = block;
+			goto got_block;
+		}
+		return retval;
+	}
+	retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
+	if (retval)
+		return retval;
+	offset = block - extent.e_lblk;
+	if (block >= extent.e_lblk && (offset <= extent.e_len)) {
+		*phys_blk = extent.e_pblk + offset;
+		if (ret_flags && extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
+			*ret_flags |= BMAP_RET_UNINIT;
+	}
+got_block:
+	if ((*phys_blk == 0) && (bmap_flags & BMAP_ALLOC)) {
+		implied_cluster_alloc(fs, ino, inode, handle, block, &blk64);
+		if (blk64)
+			goto set_extent;
+		retval = extent_bmap(fs, ino, inode, handle, block_buf,
+				     0, block-1, 0, blocks_alloc, &blk64);
+		if (retval)
+			blk64 = ext2fs_find_inode_goal(fs, ino, inode, block);
+		alloc_ctx.ino = ino;
+		alloc_ctx.inode = inode;
+		alloc_ctx.lblk = extent.e_lblk;
+		alloc_ctx.flags = BLOCK_ALLOC_DATA;
+		retval = ext2fs_alloc_block3(fs, blk64, block_buf, &blk64,
+					     &alloc_ctx);
+		if (retval)
+			return retval;
+		blk64 &= ~EXT2FS_CLUSTER_MASK(fs);
+		blk64 += EXT2FS_CLUSTER_MASK(fs) & block;
+		alloc++;
+	set_extent:
+		retval = ext2fs_extent_set_bmap(handle, block,
+						blk64, set_flags);
+		if (retval) {
+			ext2fs_block_alloc_stats2(fs, blk64, -1);
+			return retval;
+		}
+		/* Update inode after setting extent */
+		retval = ext2fs_read_inode(fs, ino, inode);
+		if (retval)
+			return retval;
+		*blocks_alloc += alloc;
+		*phys_blk = blk64;
+	}
+	return 0;
+}
+
+int ext2fs_file_block_offset_too_big(ext2_filsys fs,
+				     struct ext2_inode *inode,
+				     blk64_t offset)
+{
+	blk64_t addr_per_block, max_map_block;
+
+	/* Kernel seems to cut us off at 4294967294 blocks */
+	if (offset >= (1ULL << 32) - 1)
+		return 1;
+
+	if (inode->i_flags & EXT4_EXTENTS_FL)
+		return 0;
+
+	addr_per_block = fs->blocksize >> 2;
+	max_map_block = addr_per_block;
+	max_map_block += addr_per_block * addr_per_block;
+	max_map_block += addr_per_block * addr_per_block * addr_per_block;
+	max_map_block += 12;
+
+	return offset >= max_map_block;
+}
+
+errcode_t ext2fs_bmap2(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode,
+		       char *block_buf, int bmap_flags, blk64_t block,
+		       int *ret_flags, blk64_t *phys_blk)
+{
+	struct ext2_inode inode_buf;
+	ext2_extent_handle_t handle = 0;
+	blk_t addr_per_block;
+	blk_t	b, blk32;
+	blk64_t b64;
+	char	*buf = 0;
+	errcode_t	retval = 0;
+	int		blocks_alloc = 0, inode_dirty = 0;
+	struct blk_alloc_ctx alloc_ctx = {
+		.ino	= ino,
+		.inode	= inode,
+		.lblk	= 0,
+		.flags	= BLOCK_ALLOC_DATA,
+	};
+
+	if (!(bmap_flags & BMAP_SET))
+		*phys_blk = 0;
+
+	if (ret_flags)
+		*ret_flags = 0;
+
+	/* Read inode structure if necessary */
+	if (!inode) {
+		retval = ext2fs_read_inode(fs, ino, &inode_buf);
+		if (retval)
+			return retval;
+		inode = &inode_buf;
+	}
+	addr_per_block = (blk_t) fs->blocksize >> 2;
+
+	if (ext2fs_file_block_offset_too_big(fs, inode, block))
+		return EXT2_ET_FILE_TOO_BIG;
+
+	/*
+	 * If an inode has inline data, that means that it doesn't have
+	 * any blocks and we shouldn't map any blocks for it.
+	 */
+	if (inode->i_flags & EXT4_INLINE_DATA_FL)
+		return EXT2_ET_INLINE_DATA_NO_BLOCK;
+
+	if (!block_buf) {
+		retval = ext2fs_get_array(2, fs->blocksize, &buf);
+		if (retval)
+			return retval;
+		block_buf = buf;
+	}
+
+	if (inode->i_flags & EXT4_EXTENTS_FL) {
+		retval = ext2fs_extent_open2(fs, ino, inode, &handle);
+		if (retval)
+			goto done;
+		retval = extent_bmap(fs, ino, inode, handle, block_buf,
+				     bmap_flags, block, ret_flags,
+				     &blocks_alloc, phys_blk);
+		goto done;
+	}
+
+	if (block < EXT2_NDIR_BLOCKS) {
+		if (bmap_flags & BMAP_SET) {
+			b = *phys_blk;
+			inode_bmap(inode, block) = b;
+			inode_dirty++;
+			goto done;
+		}
+
+		*phys_blk = inode_bmap(inode, block);
+		b = block ? inode_bmap(inode, block - 1) :
+			    ext2fs_find_inode_goal(fs, ino, inode, block);
+
+		if ((*phys_blk == 0) && (bmap_flags & BMAP_ALLOC)) {
+			b64 = b;
+			retval = ext2fs_alloc_block3(fs, b64, block_buf, &b64,
+						     &alloc_ctx);
+			b = b64;
+			if (retval)
+				goto done;
+			inode_bmap(inode, block) = b;
+			blocks_alloc++;
+			*phys_blk = b;
+		}
+		goto done;
+	}
+
+	/* Indirect block */
+	block -= EXT2_NDIR_BLOCKS;
+	blk32 = *phys_blk;
+	if (block < addr_per_block) {
+		b = inode_bmap(inode, EXT2_IND_BLOCK);
+		if (!b) {
+			if (!(bmap_flags & BMAP_ALLOC)) {
+				if (bmap_flags & BMAP_SET)
+					retval = EXT2_ET_SET_BMAP_NO_IND;
+				goto done;
+			}
+
+			b = inode_bmap(inode, EXT2_IND_BLOCK-1);
+			b64 = b;
+			retval = ext2fs_alloc_block3(fs, b64, block_buf, &b64,
+						     &alloc_ctx);
+			b = b64;
+			if (retval)
+				goto done;
+			inode_bmap(inode, EXT2_IND_BLOCK) = b;
+			blocks_alloc++;
+		}
+		retval = block_ind_bmap(fs, bmap_flags, b, block_buf,
+					&blocks_alloc, block, &blk32);
+		if (retval == 0)
+			*phys_blk = blk32;
+		goto done;
+	}
+
+	/* Doubly indirect block  */
+	block -= addr_per_block;
+	if (block < addr_per_block * addr_per_block) {
+		b = inode_bmap(inode, EXT2_DIND_BLOCK);
+		if (!b) {
+			if (!(bmap_flags & BMAP_ALLOC)) {
+				if (bmap_flags & BMAP_SET)
+					retval = EXT2_ET_SET_BMAP_NO_IND;
+				goto done;
+			}
+
+			b = inode_bmap(inode, EXT2_IND_BLOCK);
+			b64 = b;
+			retval = ext2fs_alloc_block3(fs, b64, block_buf, &b64,
+						     &alloc_ctx);
+			b = b64;
+			if (retval)
+				goto done;
+			inode_bmap(inode, EXT2_DIND_BLOCK) = b;
+			blocks_alloc++;
+		}
+		retval = block_dind_bmap(fs, bmap_flags, b, block_buf,
+					 &blocks_alloc, block, &blk32);
+		if (retval == 0)
+			*phys_blk = blk32;
+		goto done;
+	}
+
+	/* Triply indirect block */
+	block -= addr_per_block * addr_per_block;
+	b = inode_bmap(inode, EXT2_TIND_BLOCK);
+	if (!b) {
+		if (!(bmap_flags & BMAP_ALLOC)) {
+			if (bmap_flags & BMAP_SET)
+				retval = EXT2_ET_SET_BMAP_NO_IND;
+			goto done;
+		}
+
+		b = inode_bmap(inode, EXT2_DIND_BLOCK);
+		b64 = b;
+		retval = ext2fs_alloc_block3(fs, b64, block_buf, &b64,
+					     &alloc_ctx);
+		b = b64;
+		if (retval)
+			goto done;
+		inode_bmap(inode, EXT2_TIND_BLOCK) = b;
+		blocks_alloc++;
+	}
+	retval = block_tind_bmap(fs, bmap_flags, b, block_buf,
+				 &blocks_alloc, block, &blk32);
+	if (retval == 0)
+		*phys_blk = blk32;
+done:
+	if (*phys_blk && retval == 0 && (bmap_flags & BMAP_ZERO))
+		retval = ext2fs_zero_blocks2(fs, *phys_blk, 1, NULL, NULL);
+	if (buf)
+		ext2fs_free_mem(&buf);
+	if (handle)
+		ext2fs_extent_free(handle);
+	if ((retval == 0) && (blocks_alloc || inode_dirty)) {
+		ext2fs_iblk_add_blocks(fs, inode, blocks_alloc);
+		retval = ext2fs_write_inode(fs, ino, inode);
+	}
+	return retval;
+}
+
+errcode_t ext2fs_bmap(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode,
+		      char *block_buf, int bmap_flags, blk_t block,
+		      blk_t *phys_blk)
+{
+	errcode_t ret;
+	blk64_t	ret_blk = *phys_blk;
+
+	ret = ext2fs_bmap2(fs, ino, inode, block_buf, bmap_flags, block,
+			    0, &ret_blk);
+	if (ret)
+		return ret;
+	if (ret_blk >= ((long long) 1 << 32))
+		return EOVERFLOW;
+	*phys_blk = ret_blk;
+	return 0;
+}