snapuserd: Move GetNumSectors call to snapuserd_server.
Calling this in snapuserd_core fails when the base path is a regular
file. Since the value is only read once, just call it from
snapuserd_server instead, which also means we don't have to add an
S_ISBLK check here.
Bug: 288273605
Test: snapuserd_test
Change-Id: Ic26bf807b24611f2d97829d1b4eb1d0ede2feb6a
diff --git a/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_kernel.h b/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_kernel.h
index 46952c4..0d83f47 100644
--- a/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_kernel.h
+++ b/fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_kernel.h
@@ -40,6 +40,7 @@
* multiple of 512 bytes. Hence these two constants.
*/
static constexpr uint32_t SECTOR_SHIFT = 9;
+static constexpr uint64_t SECTOR_SIZE = (1ULL << SECTOR_SHIFT);
static constexpr size_t BLOCK_SZ = 4096;
static constexpr size_t BLOCK_SHIFT = (__builtin_ffs(BLOCK_SZ) - 1);
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp
index 2dd2ec0..12d095a 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp
@@ -280,20 +280,6 @@
return false;
}
- unique_fd fd(TEMP_FAILURE_RETRY(open(base_path_merge_.c_str(), O_RDONLY | O_CLOEXEC)));
- if (fd < 0) {
- SNAP_LOG(ERROR) << "Cannot open block device";
- return false;
- }
-
- uint64_t dev_sz = get_block_device_size(fd.get());
- if (!dev_sz) {
- SNAP_LOG(ERROR) << "Failed to find block device size: " << base_path_merge_;
- return false;
- }
-
- num_sectors_ = dev_sz >> SECTOR_SHIFT;
-
return ReadMetadata();
}
@@ -460,5 +446,21 @@
merge_thread_ = nullptr;
}
+uint64_t SnapshotHandler::GetNumSectors() const {
+ unique_fd fd(TEMP_FAILURE_RETRY(open(base_path_merge_.c_str(), O_RDONLY | O_CLOEXEC)));
+ if (fd < 0) {
+ SNAP_LOG(ERROR) << "Cannot open base path: " << base_path_merge_;
+ return false;
+ }
+
+ uint64_t dev_sz = get_block_device_size(fd.get());
+ if (!dev_sz) {
+ SNAP_LOG(ERROR) << "Failed to find block device size: " << base_path_merge_;
+ return false;
+ }
+
+ return dev_sz / SECTOR_SIZE;
+}
+
} // namespace snapshot
} // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h
index cdc38c0..5fe0a70 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h
@@ -109,7 +109,7 @@
const std::string& GetControlDevicePath() { return control_device_; }
const std::string& GetMiscName() { return misc_name_; }
- const uint64_t& GetNumSectors() { return num_sectors_; }
+ uint64_t GetNumSectors() const;
const bool& IsAttached() const { return attached_; }
void AttachControlDevice() { attached_ = true; }
@@ -202,8 +202,6 @@
unique_fd cow_fd_;
- uint64_t num_sectors_;
-
std::unique_ptr<CowReader> reader_;
// chunk_vec stores the pseudo mapping of sector
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp
index c953f1a..f2585ea 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp
@@ -130,7 +130,12 @@
return Sendmsg(fd, "fail");
}
- auto retval = "success," + std::to_string(handler->snapuserd()->GetNumSectors());
+ auto num_sectors = handler->snapuserd()->GetNumSectors();
+ if (!num_sectors) {
+ return Sendmsg(fd, "fail");
+ }
+
+ auto retval = "success," + std::to_string(num_sectors);
return Sendmsg(fd, retval);
} else if (cmd == "start") {
// Message format:
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
index f3c3f67..16f9ed8 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
@@ -540,7 +540,9 @@
base_loop_->device(), 1, use_iouring, false);
ASSERT_NE(handler, nullptr);
ASSERT_NE(handler->snapuserd(), nullptr);
+#ifdef __ANDROID__
ASSERT_NE(handler->snapuserd()->GetNumSectors(), 0);
+#endif
}
void SnapuserdTest::SetDeviceControlName() {