X-Git-Url: https://git.carlh.net/gitweb/?a=blobdiff_plain;f=lwext4%2Fext4_extent.c;h=67d6b70dde366a2b93978f55bd52a1a6eaba0bd4;hb=c7c5aba4d7e3af2e3676051d14ed9512fac76bc2;hp=3b5f4e39df7f9bd6125fbc49f37ffef0f2d7f8a5;hpb=c897dc5a646527c2b87e4bc0399db59b46edbb1d;p=lwext4.git

diff --git a/lwext4/ext4_extent.c b/lwext4/ext4_extent.c
index 3b5f4e3..67d6b70 100644
--- a/lwext4/ext4_extent.c
+++ b/lwext4/ext4_extent.c
@@ -43,123 +43,15 @@
 #include "ext4_extent.h"
 #include "ext4_inode.h"
 #include "ext4_super.h"
+#include "ext4_crc32c.h"
 #include "ext4_blockdev.h"
 #include "ext4_balloc.h"
+#include "ext4_fs.h"
 
 #include <string.h>
 #include <stdlib.h>
 
-uint32_t ext4_extent_get_first_block(struct ext4_extent *extent)
-{
-	return to_le32(extent->first_block);
-}
-
-void ext4_extent_set_first_block(struct ext4_extent *extent, uint32_t iblock)
-{
-	extent->first_block = to_le32(iblock);
-}
-
-uint16_t ext4_extent_get_block_count(struct ext4_extent *extent)
-{
-	return to_le16(extent->block_count);
-}
-
-void ext4_extent_set_block_count(struct ext4_extent *extent, uint16_t count)
-{
-	extent->block_count = to_le16(count);
-}
-
-uint64_t ext4_extent_get_start(struct ext4_extent *extent)
-{
-	return ((uint64_t)to_le16(extent->start_hi)) << 32 |
-	       ((uint64_t)to_le32(extent->start_lo));
-}
-
-void ext4_extent_set_start(struct ext4_extent *extent, uint64_t fblock)
-{
-	extent->start_lo = to_le32((fblock << 32) >> 32);
-	extent->start_hi = to_le16((uint16_t)(fblock >> 32));
-}
-
-uint32_t ext4_extent_index_get_first_block(struct ext4_extent_index *index)
-{
-	return to_le32(index->first_block);
-}
-
-void ext4_extent_index_set_first_block(struct ext4_extent_index *index,
-				       uint32_t iblock)
-{
-	index->first_block = to_le32(iblock);
-}
-
-uint64_t ext4_extent_index_get_leaf(struct ext4_extent_index *index)
-{
-	return ((uint64_t)to_le16(index->leaf_hi)) << 32 |
-	       ((uint64_t)to_le32(index->leaf_lo));
-}
-
-void ext4_extent_index_set_leaf(struct ext4_extent_index *index,
-				uint64_t fblock)
-{
-	index->leaf_lo = to_le32((fblock << 32) >> 32);
-	index->leaf_hi = to_le16((uint16_t)(fblock >> 32));
-}
-
-uint16_t ext4_extent_header_get_magic(struct ext4_extent_header *header)
-{
-	return to_le16(header->magic);
-}
-
-void ext4_extent_header_set_magic(struct ext4_extent_header *header,
-				  uint16_t magic)
-{
-	header->magic = to_le16(magic);
-}
-
-uint16_t ext4_extent_header_get_entries_count(struct ext4_extent_header *header)
-{
-	return to_le16(header->entries_count);
-}
-
-void ext4_extent_header_set_entries_count(struct ext4_extent_header *header,
-					  uint16_t count)
-{
-	header->entries_count = to_le16(count);
-}
-
-uint16_t
-ext4_extent_header_get_max_entries_count(struct ext4_extent_header *header)
-{
-	return to_le16(header->max_entries_count);
-}
-
-void ext4_extent_header_set_max_entries_count(struct ext4_extent_header *header,
-					      uint16_t max_count)
-{
-	header->max_entries_count = to_le16(max_count);
-}
-
-uint16_t ext4_extent_header_get_depth(struct ext4_extent_header *header)
-{
-	return to_le16(header->depth);
-}
-
-void ext4_extent_header_set_depth(struct ext4_extent_header *header,
-				  uint16_t depth)
-{
-	header->depth = to_le16(depth);
-}
-
-uint32_t ext4_extent_header_get_generation(struct ext4_extent_header *header)
-{
-	return to_le32(header->generation);
-}
-
-void ext4_extent_header_set_generation(struct ext4_extent_header *header,
-				       uint32_t generation)
-{
-	header->generation = to_le32(generation);
-}
+#if !CONFIG_EXTENT_FULL
 
 /**@brief Binary search in extent index node.
  * @param header Extent header of index node
@@ -233,8 +125,69 @@ static void ext4_extent_binsearch(struct ext4_extent_header *header,
 	*extent = l - 1;
 }
 
-int ext4_extent_find_block(struct ext4_inode_ref *inode_ref, uint32_t iblock,
-			   uint32_t *fblock)
+static uint32_t ext4_ext_block_csum(struct ext4_inode_ref *inode_ref,
+				    struct ext4_extent_header *eh)
+{
+	uint32_t checksum = 0;
+	struct ext4_sblock *sb = &inode_ref->fs->sb;
+
+	if (ext4_sb_has_feature_read_only(sb,
+				EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
+		uint32_t ino_index = to_le32(inode_ref->index);
+		uint32_t ino_gen =
+			to_le32(ext4_inode_get_generation(inode_ref->inode));
+		/* First calculate crc32 checksum against fs uuid */
+		checksum = ext4_crc32c(~0, sb->uuid, sizeof(sb->uuid));
+		/* Then calculate crc32 checksum against inode number
+		 * and inode generation */
+		checksum = ext4_crc32c(checksum, &ino_index,
+				     sizeof(ino_index));
+		checksum = ext4_crc32c(checksum, &ino_gen,
+				     sizeof(ino_gen));
+		/* Finally calculate crc32 checksum against 
+		 * the entire extent block up to the checksum field */
+		checksum = ext4_crc32c(checksum, eh,
+				EXT4_EXTENT_TAIL_OFFSET(eh));
+	}
+	return checksum;
+}
+
+static struct ext4_extent_header *ext_block_hdr(struct ext4_block *block)
+{
+	return (struct ext4_extent_header *)block->data;
+}
+
+static struct ext4_extent_tail *
+find_ext4_extent_tail(struct ext4_extent_header *eh)
+{
+	return (struct ext4_extent_tail *)(((char *)eh) +
+					   EXT4_EXTENT_TAIL_OFFSET(eh));
+}
+
+/*
+ * BIG FAT NOTES:
+ *       Currently we do not verify the checksum of extent
+ *       (only the case in ext4_extent.c)
+ */
+
+static void ext4_extent_block_csum_set(struct ext4_inode_ref *inode_ref,
+				       struct ext4_extent_header *eh)
+{
+	struct ext4_extent_tail *tail;
+
+	tail = find_ext4_extent_tail(eh);
+	tail->et_checksum = to_le32(ext4_ext_block_csum(inode_ref, eh));
+}
+
+/**@brief Get physical block in the extent tree by logical block number.
+ * There is no need to save path in the tree during this algorithm.
+ * @param inode_ref I-node to load block from
+ * @param iblock    Logical block number to find
+ * @param fblock    Output value for physical block number
+ * @return Error code*/
+static int
+ext4_extent_find_block(struct ext4_inode_ref *inode_ref, uint32_t iblock,
+			   ext4_fsblk_t *fblock)
 {
 	int rc;
 	/* Compute bound defined by i-node size */
@@ -288,7 +241,7 @@ int ext4_extent_find_block(struct ext4_inode_ref *inode_ref, uint32_t iblock,
 		*fblock = 0;
 	} else {
 		/* Compute requested physical block address */
-		uint32_t phys_block;
+		ext4_fsblk_t phys_block;
 		uint32_t first = ext4_extent_get_first_block(extent);
 		phys_block = ext4_extent_get_start(extent) + iblock - first;
 
@@ -416,7 +369,7 @@ static int ext4_extent_release(struct ext4_inode_ref *inode_ref,
 static int ext4_extent_release_branch(struct ext4_inode_ref *inode_ref,
 				      struct ext4_extent_index *index)
 {
-	uint32_t fblock = ext4_extent_index_get_leaf(index);
+	ext4_fsblk_t fblock = ext4_extent_index_get_leaf(index);
 	uint32_t i;
 	struct ext4_block block;
 	int rc = ext4_block_get(inode_ref->fs->bdev, &block, fblock);
@@ -458,13 +411,16 @@ static int ext4_extent_release_branch(struct ext4_inode_ref *inode_ref,
 	return ext4_balloc_free_block(inode_ref, fblock);
 }
 
-int ext4_extent_release_blocks_from(struct ext4_inode_ref *inode_ref,
-				    uint32_t iblock_from)
+int ext4_extent_remove_space(struct ext4_inode_ref *inode_ref, ext4_lblk_t from,
+			     ext4_lblk_t to)
 {
+	if (to != EXT_MAX_BLOCKS)
+		return ENOTSUP;
+
 	/* Find the first extent to modify */
 	struct ext4_extent_path *path;
 	uint16_t i;
-	int rc = ext4_extent_find_extent(inode_ref, iblock_from, &path);
+	int rc = ext4_extent_find_extent(inode_ref, from, &path);
 	if (rc != EOK)
 		return rc;
 
@@ -477,8 +433,8 @@ int ext4_extent_release_blocks_from(struct ext4_inode_ref *inode_ref,
 
 	/* First extent maybe released partially */
 	uint32_t first_iblock = ext4_extent_get_first_block(path_ptr->extent);
-	uint32_t first_fblock = ext4_extent_get_start(path_ptr->extent) +
-				iblock_from - first_iblock;
+	ext4_fsblk_t first_fblock = ext4_extent_get_start(path_ptr->extent) +
+				from - first_iblock;
 
 	uint16_t block_count = ext4_extent_get_block_count(path_ptr->extent);
 
@@ -493,7 +449,8 @@ int ext4_extent_release_blocks_from(struct ext4_inode_ref *inode_ref,
 
 	/* Correct counter */
 	block_count -= delete_count;
-	ext4_extent_set_block_count(path_ptr->extent, block_count);
+	ext4_extent_set_block_count(path_ptr->extent, block_count,
+				EXT4_EXT_IS_UNWRITTEN(path_ptr->extent));
 
 	/* Initialize the following loop */
 	uint16_t entries =
@@ -521,6 +478,7 @@ int ext4_extent_release_blocks_from(struct ext4_inode_ref *inode_ref,
 	}
 
 	ext4_extent_header_set_entries_count(path_ptr->header, entries);
+	ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&path_ptr->block));
 	path_ptr->block.dirty = true;
 
 	/* If leaf node is empty, parent entry must be modified */
@@ -562,6 +520,7 @@ int ext4_extent_release_blocks_from(struct ext4_inode_ref *inode_ref,
 		}
 
 		ext4_extent_header_set_entries_count(path_ptr->header, entries);
+		ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&path_ptr->block));
 		path_ptr->block.dirty = true;
 
 		/* Free the node if it is empty */
@@ -626,8 +585,12 @@ static int ext4_extent_append_extent(struct ext4_inode_ref *inode_ref,
 
 		if (entries == limit) {
 			/* Full node - allocate block for new one */
-			uint32_t fblock;
-			int rc = ext4_balloc_alloc_block(inode_ref, &fblock);
+			ext4_fsblk_t goal, fblock;
+			int rc = ext4_fs_indirect_find_goal(inode_ref, &goal);
+			if (rc != EOK)
+				return rc;
+
+			rc = ext4_balloc_alloc_block(inode_ref, goal, &fblock);
 			if (rc != EOK)
 				return rc;
 
@@ -685,6 +648,7 @@ static int ext4_extent_append_extent(struct ext4_inode_ref *inode_ref,
 						     path_ptr->depth);
 			ext4_extent_header_set_generation(path_ptr->header, 0);
 
+			ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&path_ptr->block));
 			path_ptr->block.dirty = true;
 
 			/* Jump to the preceding item */
@@ -710,6 +674,7 @@ static int ext4_extent_append_extent(struct ext4_inode_ref *inode_ref,
 
 			ext4_extent_header_set_entries_count(path_ptr->header,
 							     entries + 1);
+			ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&path_ptr->block));
 			path_ptr->block.dirty = true;
 
 			/* No more splitting needed */
@@ -725,8 +690,12 @@ static int ext4_extent_append_extent(struct ext4_inode_ref *inode_ref,
 	uint16_t limit = ext4_extent_header_get_max_entries_count(path->header);
 
 	if (entries == limit) {
-		uint32_t new_fblock;
-		int rc = ext4_balloc_alloc_block(inode_ref, &new_fblock);
+		ext4_fsblk_t goal, new_fblock;
+		int rc = ext4_fs_indirect_find_goal(inode_ref, &goal);
+		if (rc != EOK)
+			return rc;
+
+		rc = ext4_balloc_alloc_block(inode_ref, goal, &new_fblock);
 		if (rc != EOK)
 			return rc;
 
@@ -788,6 +757,7 @@ static int ext4_extent_append_extent(struct ext4_inode_ref *inode_ref,
 		ext4_extent_header_set_max_entries_count(old_root->header,
 							 limit);
 
+		ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&old_root->block));
 		old_root->block.dirty = true;
 
 		/* Re-initialize new root metadata */
@@ -804,6 +774,8 @@ static int ext4_extent_append_extent(struct ext4_inode_ref *inode_ref,
 		ext4_extent_index_set_first_block(new_root->index, 0);
 		ext4_extent_index_set_leaf(new_root->index, new_fblock);
 
+		/* Since new_root belongs to on-disk inode,
+		 * we don't do checksum here */
 		new_root->block.dirty = true;
 	} else {
 		if (path->depth) {
@@ -819,16 +791,29 @@ static int ext4_extent_append_extent(struct ext4_inode_ref *inode_ref,
 		}
 
 		ext4_extent_header_set_entries_count(path->header, entries + 1);
+		/* Since new_root belongs to on-disk inode,
+		 * we don't do checksum here */
 		path->block.dirty = true;
 	}
 
 	return EOK;
 }
 
-int ext4_extent_append_block(struct ext4_inode_ref *inode_ref, uint32_t *iblock,
-			     uint32_t *fblock, bool update_size)
+/**@brief Append data block to the i-node.
+ * This function allocates data block, tries to append it
+ * to some existing extent or creates new extents.
+ * It includes possible extent tree modifications (splitting).
+ * @param inode_ref I-node to append block to
+ * @param iblock    Output logical number of newly allocated block
+ * @param fblock    Output physical block address of newly allocated block
+ *
+ * @return Error code*/
+static int
+ext4_extent_append_block(struct ext4_inode_ref *inode_ref, uint32_t *iblock,
+			     ext4_fsblk_t *fblock, bool update_size)
 {
 	uint16_t i;
+	ext4_fsblk_t goal;
 	struct ext4_sblock *sb = &inode_ref->fs->sb;
 	uint64_t inode_size = ext4_inode_get_size(sb, inode_ref->inode);
 	uint32_t block_size = ext4_sb_get_block_size(sb);
@@ -860,12 +845,16 @@ int ext4_extent_append_block(struct ext4_inode_ref *inode_ref, uint32_t *iblock,
 	uint16_t block_count = ext4_extent_get_block_count(path_ptr->extent);
 	uint16_t block_limit = (1 << 15);
 
-	uint32_t phys_block = 0;
+	ext4_fsblk_t phys_block = 0;
 	if (block_count < block_limit) {
 		/* There is space for new block in the extent */
 		if (block_count == 0) {
+			int rc = ext4_fs_indirect_find_goal(inode_ref, &goal);
+			if (rc != EOK)
+				goto finish;
+
 			/* Existing extent is empty */
-			rc = ext4_balloc_alloc_block(inode_ref, &phys_block);
+			rc = ext4_balloc_alloc_block(inode_ref, goal, &phys_block);
 			if (rc != EOK)
 				goto finish;
 
@@ -873,7 +862,8 @@ int ext4_extent_append_block(struct ext4_inode_ref *inode_ref, uint32_t *iblock,
 			ext4_extent_set_first_block(path_ptr->extent,
 						    new_block_idx);
 			ext4_extent_set_start(path_ptr->extent, phys_block);
-			ext4_extent_set_block_count(path_ptr->extent, 1);
+			ext4_extent_set_block_count(path_ptr->extent, 1,
+						false);
 
 			/* Update i-node */
 			if (update_size) {
@@ -882,10 +872,16 @@ int ext4_extent_append_block(struct ext4_inode_ref *inode_ref, uint32_t *iblock,
 				inode_ref->dirty = true;
 			}
 
+			ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&path_ptr->block));
 			path_ptr->block.dirty = true;
 
 			goto finish;
 		} else {
+			ext4_fsblk_t goal;
+			int rc = ext4_fs_indirect_find_goal(inode_ref, &goal);
+			if (rc != EOK)
+				goto finish;
+
 			/* Existing extent contains some blocks */
 			phys_block = ext4_extent_get_start(path_ptr->extent);
 			phys_block +=
@@ -908,7 +904,8 @@ int ext4_extent_append_block(struct ext4_inode_ref *inode_ref, uint32_t *iblock,
 
 			/* Update extent */
 			ext4_extent_set_block_count(path_ptr->extent,
-						    block_count + 1);
+						    block_count + 1,
+						    false);
 
 			/* Update i-node */
 			if (update_size) {
@@ -917,6 +914,7 @@ int ext4_extent_append_block(struct ext4_inode_ref *inode_ref, uint32_t *iblock,
 				inode_ref->dirty = true;
 			}
 
+			ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&path_ptr->block));
 			path_ptr->block.dirty = true;
 
 			goto finish;
@@ -927,8 +925,12 @@ append_extent:
 	/* Append new extent to the tree */
 	phys_block = 0;
 
+	rc = ext4_fs_indirect_find_goal(inode_ref, &goal);
+	if (rc != EOK)
+		goto finish;
+
 	/* Allocate new data block */
-	rc = ext4_balloc_alloc_block(inode_ref, &phys_block);
+	rc = ext4_balloc_alloc_block(inode_ref, goal, &phys_block);
 	if (rc != EOK)
 		goto finish;
 
@@ -943,7 +945,7 @@ append_extent:
 	path_ptr = path + tree_depth;
 
 	/* Initialize newly created extent */
-	ext4_extent_set_block_count(path_ptr->extent, 1);
+	ext4_extent_set_block_count(path_ptr->extent, 1, false);
 	ext4_extent_set_first_block(path_ptr->extent, new_block_idx);
 	ext4_extent_set_start(path_ptr->extent, phys_block);
 
@@ -953,6 +955,7 @@ append_extent:
 		inode_ref->dirty = true;
 	}
 
+	ext4_extent_block_csum_set(inode_ref, ext_block_hdr(&path_ptr->block));
 	path_ptr->block.dirty = true;
 
 finish:
@@ -979,6 +982,29 @@ finish:
 	return rc;
 }
 
+int ext4_extent_get_blocks(struct ext4_inode_ref *inode_ref, ext4_fsblk_t iblock,
+			   ext4_lblk_t max_blocks, ext4_fsblk_t *result, bool create,
+			   ext4_lblk_t *blocks_count)
+{
+	uint32_t iblk = iblock;
+	ext4_fsblk_t fblk = 0;
+	int r;
+
+	if (blocks_count)
+		return ENOTSUP;
+	if (max_blocks != 1)
+		return ENOTSUP;
+
+	if (!create)
+		r = ext4_extent_find_block(inode_ref, iblk, &fblk);
+	else
+		r = ext4_extent_append_block(inode_ref, &iblk, &fblk, false);
+
+	*result = fblk;
+	return r;
+}
+
+#endif
 /**
  * @}
  */