:: commit 134fd3c8bd11c60560099c5617d11f9c442f617e

mintsuki <mintsuki@protonmail.com> — 2021-09-01 21:01

parents: 0af91feaef

disk: Use a different method to match EFI_HANDLEs with volumes

diff --git a/stage23/drivers/disk.s2.c b/stage23/drivers/disk.s2.c
index e8e22529..93ce3b85 100644
--- a/stage23/drivers/disk.s2.c
+++ b/stage23/drivers/disk.s2.c
@@ -205,86 +205,116 @@ void disk_create_index(void) {
 
 #if uefi == 1
 
-struct volume *disk_volume_from_efi_handle(EFI_HANDLE efi_handle) {
+bool disk_read_sectors(struct volume *volume, void *buf, uint64_t block, size_t count) {
     EFI_STATUS status;
 
-    struct volume *ret = NULL;
+    status = volume->block_io->ReadBlocks(volume->block_io,
+                               volume->block_io->Media->MediaId,
+                               block, count * volume->sector_size, buf);
+    if (status != 0) {
+        return false;
+    }
+
+    return true;
+}
+
+static uint8_t unique_sector_pool[8192] __attribute__((aligned(4096)));
+
+struct volume *disk_volume_from_efi_handle(EFI_HANDLE efi_handle) {
+    EFI_STATUS status;
 
-    EFI_GUID disk_io_guid = DISK_IO_PROTOCOL;
     EFI_GUID block_io_guid = BLOCK_IO_PROTOCOL;
-    EFI_DISK_IO *disk_io = NULL;
     EFI_BLOCK_IO *block_io = NULL;
 
-    status = gBS->HandleProtocol(efi_handle, &disk_io_guid, (void **)&disk_io);
-    if (status)
-        return NULL;
     status = gBS->HandleProtocol(efi_handle, &block_io_guid, (void **)&block_io);
-    if (status)
+    if (status) {
+        printv("Failed to match handle %X (1)\n", efi_handle);
         return NULL;
+    }
 
-    uint64_t signature = BUILD_ID;
-    uint64_t orig;
-
-    disk_io->ReadDisk(disk_io, block_io->Media->MediaId, 0, sizeof(uint64_t), &orig);
+    for (size_t i = 0; i < volume_index_i; i++) {
+        if (volume_index[i]->unique_sector_valid == false) {
+            continue;
+        }
 
-    status = disk_io->WriteDisk(disk_io, block_io->Media->MediaId, 0, sizeof(uint64_t), &signature);
+        size_t unique_sector = (volume_index[i]->unique_sector * volume_index[i]->sector_size) / block_io->Media->BlockSize;
 
-    if (status) {
-        // Really hacky support for CDs because they are read-only
-        for (size_t i = 0; i < volume_index_i; i++) {
-            if (volume_index[i]->is_optical)
-                return volume_index[i];
+        status = block_io->ReadBlocks(block_io, block_io->Media->MediaId,
+                                      unique_sector,
+                                      volume_index[i]->sector_size,
+                                      unique_sector_pool);
+        if (status != 0) {
+            continue;
         }
 
-        return NULL;
-    }
+        uint32_t crc32 = get_crc32(unique_sector_pool, volume_index[i]->sector_size);
 
-    for (size_t i = 0; i < volume_index_i; i++) {
-        uint64_t compare;
+        if (crc32 == volume_index[i]->unique_sector_crc32) {
+            printv("Matched handle %X with volume %X\n", efi_handle, volume_index[i]);
+            return volume_index[i];
+        }
+    }
 
-        EFI_DISK_IO *cur_disk_io = NULL;
-        EFI_BLOCK_IO *cur_block_io = NULL;
+    printv("Failed to match handle %X (2)\n", efi_handle);
 
-        gBS->HandleProtocol(volume_index[i]->efi_handle,
-                          &disk_io_guid, (void **)&cur_disk_io);
-        gBS->HandleProtocol(volume_index[i]->efi_handle,
-                          &block_io_guid, (void **)&cur_block_io);
+    return NULL;
+}
 
-        cur_disk_io->ReadDisk(cur_disk_io,
-                          cur_block_io->Media->MediaId,
-                          0 +
-                          volume_index[i]->first_sect * volume_index[i]->sector_size,
-                          sizeof(uint64_t), &compare);
+static struct volume *volume_by_unique_sector(size_t sect, uint32_t crc32) {
+    for (size_t i = 0; i < volume_index_i; i++) {
+        if (volume_index[i]->unique_sector_valid == false) {
+            continue;
+        }
 
-        if (compare == signature) {
-            ret = volume_index[i];
-            break;
+        if (volume_index[i]->unique_sector == sect
+         && volume_index[i]->unique_sector_crc32 == crc32) {
+            return volume_index[i];
         }
     }
 
-    disk_io->WriteDisk(disk_io, block_io->Media->MediaId, 0, sizeof(uint64_t), &orig);
-
-    return ret;
+    return NULL;
 }
 
-bool disk_read_sectors(struct volume *volume, void *buf, uint64_t block, size_t count) {
+#define UNIQUE_SECT_MAX_SEARCH_RANGE 0x1000
+
+static void find_unique_sectors(void) {
     EFI_STATUS status;
 
-    EFI_GUID block_io_guid = BLOCK_IO_PROTOCOL;
-    EFI_BLOCK_IO *block_io = NULL;
+    for (size_t i = 0; i < volume_index_i; i++) {
+        for (size_t j = 0; j < UNIQUE_SECT_MAX_SEARCH_RANGE; j++) {
+            if (volume_index[i]->first_sect % (volume_index[i]->sector_size / 512)) {
+                break;
+            }
 
-    status = gBS->HandleProtocol(volume->efi_handle,
-                               &block_io_guid, (void **)&block_io);
+            size_t first_sect = volume_index[i]->first_sect / (volume_index[i]->sector_size / 512);
 
-    status = block_io->ReadBlocks(block_io,
-                               block_io->Media->MediaId,
-                               block, count * volume->sector_size, buf);
+            status = volume_index[i]->block_io->ReadBlocks(
+                                volume_index[i]->block_io,
+                                volume_index[i]->block_io->Media->MediaId,
+                                first_sect + j,
+                                volume_index[i]->sector_size,
+                                unique_sector_pool);
+            if (status != 0) {
+                break;
+            }
 
-    if (status != 0) {
-        return false;
-    }
+            uint32_t crc32 = get_crc32(unique_sector_pool, volume_index[i]->sector_size);
 
-    return true;
+            if (volume_by_unique_sector(j, crc32) == NULL) {
+                volume_index[i]->unique_sector_valid = true;
+                volume_index[i]->unique_sector = j;
+                volume_index[i]->unique_sector_crc32 = crc32;
+                break;
+            }
+        }
+
+        if (volume_index[i]->unique_sector_valid == false) {
+            printv("Not able to match unique sector for volume %X\n", volume_index[i]);
+        } else {
+            printv("Matched volume %X with uniq: %U, crc32: %x\n",
+                    volume_index[i]->unique_sector, volume_index[i]->unique_sector_crc32);
+        }
+    }
 }
 
 void disk_create_index(void) {
@@ -339,6 +369,7 @@ void disk_create_index(void) {
         }
 
         block->efi_handle = handles[i];
+        block->block_io = drive;
         block->partition = 0;
         block->sector_size = drive->Media->BlockSize;
         block->first_sect = 0;
@@ -368,6 +399,8 @@ void disk_create_index(void) {
             block->max_partition++;
         }
     }
+
+    find_unique_sectors();
 }
 
 #endif
diff --git a/stage23/lib/blib.c b/stage23/lib/blib.c
index eff945b5..747fb72c 100644
--- a/stage23/lib/blib.c
+++ b/stage23/lib/blib.c
@@ -83,6 +83,65 @@ size_t get_trailing_zeros(uint64_t val) {
     return 64;
 }
 
+// This table from https://web.mit.edu/freebsd/head/sys/libkern/crc32.c
+static const uint32_t crc32_table[] = {
+	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
+	0xe963a535, 0x9e6495a3,	0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
+	0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
+	0xf3b97148, 0x84be41de,	0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
+	0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,	0x14015c4f, 0x63066cd9,
+	0xfa0f3d63, 0x8d080df5,	0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
+	0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,	0x35b5a8fa, 0x42b2986c,
+	0xdbbbc9d6, 0xacbcf940,	0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
+	0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
+	0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
+	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,	0x76dc4190, 0x01db7106,
+	0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
+	0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
+	0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
+	0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
+	0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
+	0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
+	0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
+	0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
+	0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
+	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
+	0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
+	0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
+	0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
+	0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
+	0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
+	0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
+	0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
+	0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
+	0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
+	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
+	0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
+	0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
+	0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
+	0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
+	0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
+	0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
+	0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
+	0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
+	0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
+	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
+	0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
+	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
+};
+
+uint32_t get_crc32(void *_stream, size_t len) {
+    uint8_t *stream = _stream;
+    uint32_t ret = 0xffffffff;
+
+    for (size_t i = 0; i < len; i++) {
+        ret = (ret >> 8) ^ crc32_table[(ret ^ stream[i]) & 0xff];
+    }
+
+    ret ^= 0xffffffff;
+    return ret;
+}
+
 #if uefi == 1
 
 bool efi_boot_services_exited = false;
diff --git a/stage23/lib/blib.h b/stage23/lib/blib.h
index a86502c2..e0caa157 100644
--- a/stage23/lib/blib.h
+++ b/stage23/lib/blib.h
@@ -36,6 +36,8 @@ extern bool verbose;
 
 bool parse_resolution(size_t *width, size_t *height, size_t *bpp, const char *buf);
 
+uint32_t get_crc32(void *_stream, size_t len);
+
 uint64_t sqrt(uint64_t a_nInput);
 size_t get_trailing_zeros(uint64_t val);
 
diff --git a/stage23/lib/part.h b/stage23/lib/part.h
index 72fa2b18..b6de033e 100644
--- a/stage23/lib/part.h
+++ b/stage23/lib/part.h
@@ -16,6 +16,11 @@
 struct volume {
 #if uefi == 1
     EFI_HANDLE efi_handle;
+    EFI_BLOCK_IO *block_io;
+
+    bool unique_sector_valid;
+    size_t unique_sector;
+    uint32_t unique_sector_crc32;
 #elif bios == 1
     int drive;
 #endif
diff --git a/stage23/lib/part.s2.c b/stage23/lib/part.s2.c
index b207f0ab..5e187a25 100644
--- a/stage23/lib/part.s2.c
+++ b/stage23/lib/part.s2.c
@@ -26,8 +26,14 @@ static bool cache_block(struct volume *volume, uint64_t block) {
         volume->cache =
             ext_mem_alloc(volume->fastest_xfer_size * volume->sector_size);
 
+    if (volume->first_sect % (volume->sector_size / 512)) {
+        return false;
+    }
+
+    size_t first_sect = volume->first_sect / (volume->sector_size / 512);
+
     if (!disk_read_sectors(volume, volume->cache,
-                           volume->first_sect + block * volume->fastest_xfer_size,
+                           first_sect + block * volume->fastest_xfer_size,
                            volume->fastest_xfer_size))
         return false;
 
@@ -103,7 +109,7 @@ struct gpt_entry {
 bool gpt_get_guid(struct guid *guid, struct volume *volume) {
     struct gpt_table_header header = {0};
 
-    int sector_size = volume->sector_size;
+    int sector_size = 512;
 
     // read header, located after the first block
     volume_read(volume, &header, sector_size * 1, sizeof(header));
@@ -123,7 +129,7 @@ bool gpt_get_guid(struct guid *guid, struct volume *volume) {
 static int gpt_get_part(struct volume *ret, struct volume *volume, int partition) {
     struct gpt_table_header header = {0};
 
-    int sector_size = volume->sector_size;
+    int sector_size = 512;
 
     // read header, located after the first block
     volume_read(volume, &header, sector_size * 1, sizeof(header));
@@ -150,6 +156,7 @@ static int gpt_get_part(struct volume *ret, struct volume *volume, int partition
 
 #if uefi == 1
     ret->efi_handle  = volume->efi_handle;
+    ret->block_io    = volume->block_io;
 #elif bios == 1
     ret->drive       = volume->drive;
 #endif
@@ -157,7 +164,7 @@ static int gpt_get_part(struct volume *ret, struct volume *volume, int partition
     ret->index       = volume->index;
     ret->is_optical  = volume->is_optical;
     ret->partition   = partition + 1;
-    ret->sector_size = sector_size;
+    ret->sector_size = volume->sector_size;
     ret->first_sect  = entry.starting_lba;
     ret->sect_count  = (entry.ending_lba - entry.starting_lba) + 1;
     ret->backing_dev = volume;
@@ -192,7 +199,7 @@ static int mbr_get_logical_part(struct volume *ret, struct volume *extended_part
     size_t ebr_sector = 0;
 
     for (int i = 0; i < partition; i++) {
-        size_t entry_offset = ebr_sector * extended_part->sector_size + 0x1ce;
+        size_t entry_offset = ebr_sector * 512 + 0x1ce;
 
         volume_read(extended_part, &entry, entry_offset, sizeof(struct mbr_entry));
 
@@ -202,7 +209,7 @@ static int mbr_get_logical_part(struct volume *ret, struct volume *extended_part
         ebr_sector = entry.first_sect;
     }
 
-    size_t entry_offset = ebr_sector * extended_part->sector_size + 0x1be;
+    size_t entry_offset = ebr_sector * 512 + 0x1be;
 
     volume_read(extended_part, &entry, entry_offset, sizeof(struct mbr_entry));
 
@@ -211,6 +218,7 @@ static int mbr_get_logical_part(struct volume *ret, struct volume *extended_part
 
 #if uefi == 1
     ret->efi_handle  = extended_part->efi_handle;
+    ret->block_io    = extended_part->block_io;
 #elif bios == 1
     ret->drive       = extended_part->drive;
 #endif
@@ -290,6 +298,7 @@ static int mbr_get_part(struct volume *ret, struct volume *volume, int partition
 
 #if uefi == 1
             extended_part.efi_handle  = volume->efi_handle;
+            extended_part.block_io    = volume->block_io;
 #elif bios == 1
             extended_part.drive       = volume->drive;
 #endif
@@ -317,6 +326,7 @@ static int mbr_get_part(struct volume *ret, struct volume *volume, int partition
 
 #if uefi == 1
     ret->efi_handle  = volume->efi_handle;
+    ret->block_io    = volume->block_io;
 #elif bios == 1
     ret->drive       = volume->drive;
 #endif
tab: 248 wrap: offon