ext4_mbr: multiple changes related to MBR parsing
authorgkostka <kostka.grzegorz@gmail.com>
Tue, 8 Dec 2015 19:06:41 +0000 (20:06 +0100)
committergkostka <kostka.grzegorz@gmail.com>
Tue, 8 Dec 2015 19:14:33 +0000 (20:14 +0100)
1. Introduce part_offset & part_size fields in blockdev
2. Blockdev operations with part_offset
3. Blockdev operations check based on part_size
4. lwext4_mbr tool: scan master boot record for linux partitions
5. Set right partition sizes in linux/windows file blockdevs

blockdev/linux/ext4_filedev.c
blockdev/windows/io_raw.c
fs_test/CMakeLists.txt
fs_test/lwext4_mbr.c [new file with mode: 0644]
lwext4/ext4_blockdev.c
lwext4/ext4_blockdev.h
lwext4/ext4_mbr.c
lwext4/ext4_mbr.h

index 2db87e3d4fa7bb555b0cf2d9c34b3bb485771888..a49e6e74a3aa322def6ad8833c5fac5f119cbbcb 100644 (file)
@@ -74,7 +74,9 @@ static int filedev_open(struct ext4_blockdev *bdev)
        if (fseeko(dev_file, 0, SEEK_END))
                return EFAULT;
 
-       _filedev.bdif->ph_bcnt = ftell(dev_file) / _filedev.bdif->ph_bsize;
+       _filedev.part_offset = 0;
+       _filedev.part_size = ftell(dev_file);
+       _filedev.bdif->ph_bcnt = _filedev.part_size / _filedev.bdif->ph_bsize;
 
        return EOK;
 }
index fad5c9d38a1f64442cbdfae8af6680e4d816edaf..9178243134c1a618bc9c6ec76bd7d54cd6f6351d 100644 (file)
@@ -93,6 +93,9 @@ static int io_raw_open(struct ext4_blockdev *bdev)
        _filedev.bdif->ph_bsize = pdg.BytesPerSector;
        _filedev.bdif->ph_bcnt = disk_size / pdg.BytesPerSector;
 
+       _filedev.part_offset = 0;
+       _filedev.part_size = disk_size;
+
        return EOK;
 }
 
index a774977ae43b3ddd407f5eabbc6b3d44618a4fd9..da9cffdb1418afec63cfcac013c420ec5c57859f 100644 (file)
@@ -18,4 +18,8 @@ target_link_libraries(lwext4_generic lwext4)
 
 add_executable(lwext4_mkfs lwext4_mkfs.c)
 target_link_libraries(lwext4_mkfs blockdev)
-target_link_libraries(lwext4_mkfs lwext4)
\ No newline at end of file
+target_link_libraries(lwext4_mkfs lwext4)
+
+add_executable(lwext4_mbr lwext4_mbr.c)
+target_link_libraries(lwext4_mbr blockdev)
+target_link_libraries(lwext4_mbr lwext4)
\ No newline at end of file
diff --git a/fs_test/lwext4_mbr.c b/fs_test/lwext4_mbr.c
new file mode 100644 (file)
index 0000000..dbf5d81
--- /dev/null
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2015 Grzegorz Kostka (kostka.grzegorz@gmail.com)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <stdbool.h>
+#include <inttypes.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+#include <ext4.h>
+#include <ext4_mbr.h>
+#include "../blockdev/linux/ext4_filedev.h"
+#include "../blockdev/windows/io_raw.h"
+
+/**@brief   Input stream name.*/
+const char *input_name = NULL;
+
+/**@brief   Block device handle.*/
+static struct ext4_blockdev *bd;
+
+/**@brief   Indicates that input is windows partition.*/
+static bool winpart = false;
+
+static bool verbose = false;
+
+static const char *usage = "                                    \n\
+Welcome in lwext4_mbr tool.                                     \n\
+Copyright (c) 2015 Grzegorz Kostka (kostka.grzegorz@gmail.com)  \n\
+Usage:                                                          \n\
+[-i] --input   - input file name (or blockdevice)               \n\
+[-w] --wpart   - windows partition mode                         \n\
+[-v] --verbose - verbose mode                                  \n\
+\n";
+
+
+static bool open_linux(void)
+{
+       ext4_filedev_filename(input_name);
+       bd = ext4_filedev_get();
+       if (!bd) {
+               printf("open_filedev: fail\n");
+               return false;
+       }
+       return true;
+}
+
+static bool open_windows(void)
+{
+#ifdef WIN32
+       ext4_io_raw_filename(input_name);
+       bd = ext4_io_raw_dev_get();
+       if (!bd) {
+               printf("open_winpartition: fail\n");
+               return false;
+       }
+       return true;
+#else
+       printf("open_winpartition: this mode should be used only under windows "
+              "!\n");
+       return false;
+#endif
+}
+
+static bool open_filedev(void)
+{
+       if (winpart) {
+               if (!open_windows())
+                       return false;
+       } else {
+               if (!open_linux())
+                       return false;
+       }
+
+       return true;
+}
+
+static bool parse_opt(int argc, char **argv)
+{
+       int option_index = 0;
+       int c;
+
+       static struct option long_options[] = {
+           {"input", required_argument, 0, 'i'},
+           {"wpart", no_argument, 0, 'w'},
+           {"verbose", no_argument, 0, 'v'},
+           {0, 0, 0, 0}};
+
+       while (-1 != (c = getopt_long(argc, argv, "i:wv",
+                                     long_options, &option_index))) {
+
+               switch (c) {
+               case 'i':
+                       input_name = optarg;
+                       break;
+               case 'w':
+                       winpart = true;
+                       break;
+               case 'v':
+                       verbose = true;
+                       break;
+               default:
+                       printf("%s", usage);
+                       return false;
+               }
+       }
+
+       return true;
+}
+
+int main(int argc, char **argv)
+{
+       int r;
+       if (!parse_opt(argc, argv)){
+               printf("parse_opt error\n");
+               return EXIT_FAILURE;
+       }
+
+       if (!open_filedev()) {
+               printf("open_filedev error\n");
+               return EXIT_FAILURE;
+       }
+
+       if (verbose)
+               ext4_dmask_set(DEBUG_ALL);
+
+       printf("ext4_mbr\n");
+       struct ext4_mbr_bdevs bdevs;
+       r = ext4_mbr_scan(bd, &bdevs);
+       if (r != EOK) {
+               printf("ext4_mbr_scan error\n");
+               return EXIT_FAILURE;
+       }
+
+       int i;
+       printf("ext4_mbr_scan:\n");
+       for (i = 0; i < 4; i++) {
+               printf("mbr_entry %d:\n", i);
+               if (!bdevs.partitions[i].bdif) {
+                       printf("\tempty/unknown\n");
+                       continue;
+               }
+
+               printf("\toffeset: 0x%llx, %lluMB\n",
+                       bdevs.partitions[i].part_offset,
+                       bdevs.partitions[i].part_offset / (1024 * 1024));
+               printf("\tsize: 0x%llx, %lluMB\n",
+                       bdevs.partitions[i].part_size,
+                       bdevs.partitions[i].part_size / (1024 * 1024));
+       }
+
+
+       return EXIT_SUCCESS;
+}
index 3af65104171bf0b3dd1d11daf646e989f81ea90c..cc209dd5e4a290a347e7aa3e176cd2bc098a1afa 100644 (file)
@@ -116,7 +116,7 @@ void ext4_block_set_lb_size(struct ext4_blockdev *bdev, uint64_t lb_bsize)
        ext4_assert(!(lb_bsize % bdev->bdif->ph_bsize));
 
        bdev->lg_bsize = lb_bsize;
-       bdev->lg_bcnt = (bdev->bdif->ph_bcnt * bdev->bdif->ph_bsize) / lb_bsize;
+       bdev->lg_bcnt = bdev->part_size / lb_bsize;
 }
 
 int ext4_block_fini(struct ext4_blockdev *bdev)
@@ -256,8 +256,7 @@ int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
 
        ext4_assert(bdev && buf);
 
-       pba = (lba * bdev->lg_bsize) / bdev->bdif->ph_bsize;
-       pba += bdev->ph_blk_offset;
+       pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
        pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 
        bdev->bread_ctr++;
@@ -272,8 +271,7 @@ int ext4_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
 
        ext4_assert(bdev && buf);
 
-       pba = (lba * bdev->lg_bsize) / bdev->bdif->ph_bsize;
-       pba += bdev->ph_blk_offset;
+       pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
        pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 
        bdev->bwrite_ctr++;
@@ -284,7 +282,6 @@ int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
                          const void *buf, uint32_t len)
 {
        uint64_t block_idx;
-       uint64_t block_end;
        uint32_t blen;
        uint32_t unalg;
        int r = EOK;
@@ -296,12 +293,11 @@ int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
        if (!bdev->bdif->ph_refctr)
                return EIO;
 
-       block_idx = (off / bdev->bdif->ph_bsize) + bdev->ph_blk_offset;
-       block_end = block_idx + len / bdev->bdif->ph_bsize;
-
-       if (!(block_end < bdev->bdif->ph_bcnt))
+       if (off + len > bdev->part_size)
                return EINVAL; /*Ups. Out of range operation*/
 
+       block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
+
        /*OK lets deal with the first possible unaligned block*/
        unalg = (off & (bdev->bdif->ph_bsize - 1));
        if (unalg) {
@@ -354,7 +350,6 @@ int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
                         uint32_t len)
 {
        uint64_t block_idx;
-       uint64_t block_end;
        uint32_t blen;
        uint32_t unalg;
        int r = EOK;
@@ -366,12 +361,11 @@ int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
        if (!bdev->bdif->ph_refctr)
                return EIO;
 
-       block_idx = (off / bdev->bdif->ph_bsize) + bdev->ph_blk_offset;
-       block_end = block_idx + len / bdev->bdif->ph_bsize;
-
-       if (!(block_end < bdev->bdif->ph_bcnt))
+       if (off + len > bdev->part_size)
                return EINVAL; /*Ups. Out of range operation*/
 
+       block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
+
        /*OK lets deal with the first possible unaligned block*/
        unalg = (off & (bdev->bdif->ph_bsize - 1));
        if (unalg) {
index 752647e1e7994cb52cee3895fe1d450f24f7a66b..482a057335b6c6a01174a61a20aa8f6c255f753f 100644 (file)
@@ -100,7 +100,10 @@ struct ext4_blockdev {
        struct ext4_blockdev_iface *bdif;
 
        /**@brief Offset in bdif. For multi partition mode.*/
-       uint64_t ph_blk_offset;
+       uint64_t part_offset;
+
+       /**@brief Part size in bdif. For multi partition mode.*/
+       uint64_t part_size;
 
        /**@brief   Block cache.*/
        struct ext4_bcache *bc;
@@ -138,6 +141,8 @@ struct ext4_blockdev {
        };                                                                     \
        static struct ext4_blockdev __name = {                                 \
                .bdif = &__name##_iface,                                       \
+               .part_offset = 0,                                              \
+               .part_size =  (__bcnt) * (__bsize),                            \
        }
 
 /**@brief   Block device initialization.
index 30a8e67cdd4435446a6bf20c8e4d5ca5cd17834a..e394ab28020df05d613eff40e416d5e8ae0f3aac 100644 (file)
  */
 
 #include "ext4_config.h"
+#include "ext4_types.h"
+#include "ext4_debug.h"
 #include "ext4_mbr.h"
 
+#include <string.h>
+
 #define MBR_SIGNATURE 0xAA55
 
 struct ext4_part_entry {
@@ -55,6 +59,58 @@ struct ext4_mbr {
 } __attribute__((packed));
 
 
+int ext4_mbr_scan(struct ext4_blockdev *parent, struct ext4_mbr_bdevs *bdevs)
+{
+       int r;
+       int i;
+
+       ext4_dbg(DEBUG_MBR, DBG_INFO "ext4_mbr_scan\n");
+       memset(bdevs, 0, sizeof(struct ext4_mbr_bdevs));
+       r = ext4_block_init(parent);
+       if (r != EOK)
+               return r;
+
+       r = ext4_block_readbytes(parent, 0, parent->bdif->ph_bbuf, 512);
+       if (r != EOK) {
+               goto blockdev_fini;
+       }
+
+       const struct ext4_mbr *mbr = (void *)parent->bdif->ph_bbuf;
+
+       if (to_le16(mbr->signature) != MBR_SIGNATURE) {
+               ext4_dbg(DEBUG_MBR, DBG_ERROR "ext4_mbr_scan: unknown "
+                        "signature: 0x%x\n", to_le16(mbr->signature));
+               r = ENOENT;
+               goto blockdev_fini;
+       }
+
+
+       for (i = 0; i < 4; ++i) {
+               const struct ext4_part_entry *pe = &mbr->part_entry[i];
+               ext4_dbg(DEBUG_MBR, "mbr_part: %d\n", i);
+               ext4_dbg(DEBUG_MBR, "\tstatus: 0x%x\n", pe->status);
+               ext4_dbg(DEBUG_MBR, "\ttype 0x%x:\n", pe->type);
+               ext4_dbg(DEBUG_MBR, "\tfirst_lba: 0x%x\n", pe->first_lba);
+               ext4_dbg(DEBUG_MBR, "\tsectors: 0x%x\n", pe->sectors);
+
+               if (!pe->sectors)
+                       continue;
+
+               if (pe->type != 0x83)
+                       continue;
+
+               bdevs->partitions[i].bdif = parent->bdif;
+               bdevs->partitions[i].part_offset =
+                               pe->first_lba * parent->bdif->ph_bsize;
+               bdevs->partitions[i].part_size =
+                               (uint64_t)pe->sectors * parent->bdif->ph_bsize;
+       }
+
+       blockdev_fini:
+       ext4_block_fini(parent);
+       return r;
+}
+
 /**
  * @}
  */
index b71a7413a6298c0c05120f357b7d04e5125fb79b..2fc91f226e36be065f165c82fa6216f9697eef2d 100644 (file)
@@ -46,7 +46,6 @@ extern "C" {
 
 /**@brief Master boot record block devices descriptor*/
 struct ext4_mbr_bdevs {
-       uint32_t cnt;
        struct ext4_blockdev partitions[4];
 };