lpmake: Pass a block size to WriteToSparseFile.

Note: The default block size is 4096.

Bug: 79173901
Test: lpmake -S can be flashed to Pixel 2
Change-Id: I44a96126edddbaedf078c3a59be3a74df89c0d74

2 files changed, 11 insertions, 1 deletions

diff --git a/partition_tools/README.md b/partition_tools/README.md
index abd38992..0993ce29 100644
--- a/partition_tools/README.md
+++ b/partition_tools/README.md
@@ -19,6 +19,7 @@ Optional arguments:
 * `--alignment=N` - By default, lpmake will align partitions to 1MiB boundaries. However, an alternate alignment can be specified if desired. This is useful for devices with a minimum I/O request size where mis-aligned partition boundaries could be a performance issue.
 * `--alignment-offset=N` - In some cases, the "super" partition is misaligned within its parent block device. This offset can be used to correct for that.
 * `--sparse` - If set, the output image will be in sparse format for flashing with fastboot. Otherwise, by default, the image will be a minimal format usable with lpdump and lpflash.
+* `-b,--block-size=N` - When writing sparse files, the device may require a specific block size. That block size can be specified here. The alignment must be a multiple of the block size. By default the block size is 4096.
 
 Example usage. This specifies a 10GB super partition for an A/B device, with a single 64MiB "cache" partition.
 
diff --git a/partition_tools/lpmake.cc b/partition_tools/lpmake.cc
index a484a2c8..25133445 100644
--- a/partition_tools/lpmake.cc
+++ b/partition_tools/lpmake.cc
@@ -45,6 +45,7 @@ static int usage(int /* argc */, char* argv[]) {
             "  -o,--output=FILE              Output file.\n"
             "\n"
             "Optional:\n"
+            "  -b,--block-size=SIZE          Physical block size, defaults to 4096.\n"
             "  -a,--alignment=N              Optimal partition alignment in bytes.\n"
             "  -O,--alignment-offset=N       Alignment offset in bytes to device parent.\n"
             "  -S,--sparse                   Output a sparse image for fastboot.\n"
@@ -67,6 +68,7 @@ int main(int argc, char* argv[]) {
         { "alignment-offset", required_argument, nullptr, 'O' },
         { "alignment", required_argument, nullptr, 'a' },
         { "sparse", no_argument, nullptr, 'S' },
+        { "block-size", required_argument, nullptr, 'b' },
         { nullptr, 0, nullptr, 0 },
     };
 
@@ -75,6 +77,7 @@ int main(int argc, char* argv[]) {
     uint32_t metadata_slots = 0;
     uint32_t alignment_offset = 0;
     uint32_t alignment = kDefaultPartitionAlignment;
+    uint32_t block_size = 4096;
     std::string output_path;
     std::vector<std::string> partitions;
     bool output_sparse = false;
@@ -124,6 +127,12 @@ int main(int argc, char* argv[]) {
             case 'S':
                 output_sparse = true;
                 break;
+            case 'b':
+                if (!android::base::ParseUint(optarg, &block_size) || !block_size) {
+                    fprintf(stderr, "Invalid argument to --block-size.\n");
+                    return EX_USAGE;
+                }
+                break;
             default:
                 break;
         }
@@ -199,7 +208,7 @@ int main(int argc, char* argv[]) {
 
     std::unique_ptr<LpMetadata> metadata = builder->Export();
     if (output_sparse) {
-        if (!WriteToSparseFile(output_path.c_str(), *metadata.get())) {
+        if (!WriteToSparseFile(output_path.c_str(), *metadata.get(), block_size)) {
             return EX_CANTCREAT;
         }
     } else if (!WriteToImageFile(output_path.c_str(), *metadata.get())) {