Changeset 1a7756a in mainline for uspace/lib/ext4/libext4_inode.c

Timestamp:

2011-10-12T09:37:59Z (14 years ago)

Author:

Frantisek Princ <frantisek.princ@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

1ccc32f

Parents:

8958a26

Message:

support for reading more complex extents (tree with nonzero depth)

File:

• uspace/lib/ext4/libext4_inode.c (modified) (2 diffs)

uspace/lib/ext4/libext4_inode.c

@@ -37 +37 @@
 
 #include <byteorder.h>
+#include <errno.h>
+#include <libblock.h>
 #include "libext4.h"
 
@@ -102 +104 @@
 }
 
-uint32_t ext4_inode_get_extent_block(ext4_inode_t *inode, uint64_t idx)
+uint32_t ext4_inode_get_extent_block(ext4_inode_t *inode, uint64_t idx, service_id_t service_id)
 {
         ext4_extent_header_t *header = ext4_inode_get_extent_header(inode);
+        ext4_extent_t *extent;
+        ext4_extent_index_t *extent_index;
 
-        if (ext4_extent_header_get_depth(header) == 0) {
+        uint32_t first_block;
+        uint16_t block_count;
+        uint64_t phys_block = 0;
+        uint64_t child;
 
-                ext4_extent_t *extent = EXT4_EXTENT_FIRST(header);
+        int rc;
+        block_t* block = NULL;
 
-                // TODO more effective searching?
+        while (ext4_extent_header_get_depth(header) != 0) {
+
+                extent_index = EXT4_EXTENT_FIRST_INDEX(header);
+
                 for (uint16_t i = 0; i < ext4_extent_header_get_entries_count(header); ++i) {
+                        if(idx >= ext4_extent_index_get_first_block(extent_index)) {
 
-                        uint32_t first = ext4_extent_get_first_block(extent);
-                        uint16_t count = ext4_extent_get_block_count(extent);
-                        uint64_t block = 0;
+                                child = ext4_extent_index_get_leaf(extent_index);
 
-                        if ((idx >= first) && (idx < first + count)) {
-                                block = ext4_extent_get_start(extent) + idx;
-                                block -= ext4_extent_get_first_block(extent);
-                                return block;
+                                if (block != NULL) {
+                                        block_put(block);
+                                }
+
+                                rc = block_get(&block, service_id, child, BLOCK_FLAGS_NONE);
+                                if (rc != EOK) {
+                                        return 0;
+                                }
+                                EXT4FS_DBG("get block");
+
+
+                                header = (ext4_extent_header_t *)block->data;
+                                break;
                         }
-                        // Go to the next extent
-                        ++extent;
                 }
         }
 
-        // TODO binary search for depth > 0
-        EXT4FS_DBG("NOT IMPLEMENTED !!!");
-        return 0;
+        extent = EXT4_EXTENT_FIRST(header);
 
+        for (uint16_t i = 0; i < ext4_extent_header_get_entries_count(header); ++i) {
+
+                first_block = ext4_extent_get_first_block(extent);
+                block_count = ext4_extent_get_block_count(extent);
+
+                if ((idx >= first_block) && (idx < first_block + block_count)) {
+                        phys_block = ext4_extent_get_start(extent) + idx;
+                        phys_block -= ext4_extent_get_first_block(extent);
+
+                        // Memory leak prevention
+                        if (block != NULL) {
+                                block_put(block);
+                        }
+                        return phys_block;
+                }
+                // Go to the next extent
+                ++extent;
+        }
+
+
+        EXT4FS_DBG("ERROR - reached function end");
+        return phys_block;
 }