Update some fs_mgr/debuggerd to use getpagesize() instead of PAGE_SIZE

Test: th
Bug: 279808236
Change-Id: I9d30cfe19d2b1a7d624cc5425e4315dc6e3b2ad2

debuggerd/crasher/crasher.cpp

@@ -148,7 +148,7 @@ noinline void abuse_heap() {
 noinline void leak() {
     while (true) {
         void* mapping =
-            mmap(nullptr, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+            mmap(nullptr, getpagesize(), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
         static_cast<volatile char*>(mapping)[0] = 'a';
     }
 }

debuggerd/debuggerd_test.cpp

@@ -300,24 +300,7 @@ void CrasherTest::AssertDeath(int signo) {
 }
 
 static void ConsumeFd(unique_fd fd, std::string* output) {
-  constexpr size_t read_length = PAGE_SIZE;
-  std::string result;
-
-  while (true) {
-    size_t offset = result.size();
-    result.resize(result.size() + PAGE_SIZE);
-    ssize_t rc = TEMP_FAILURE_RETRY(read(fd.get(), &result[offset], read_length));
-    if (rc == -1) {
-      FAIL() << "read failed: " << strerror(errno);
-    } else if (rc == 0) {
-      result.resize(result.size() - PAGE_SIZE);
-      break;
-    }
-
-    result.resize(result.size() - PAGE_SIZE + rc);
-  }
-
-  *output = std::move(result);
+  ASSERT_TRUE(android::base::ReadFdToString(fd, output));
 }
 
 class LogcatCollector {

debuggerd/handler/debuggerd_handler.cpp

@@ -721,19 +721,19 @@ void debuggerd_init(debuggerd_callbacks_t* callbacks) {
   }
 
   size_t thread_stack_pages = 8;
-  void* thread_stack_allocation = mmap(nullptr, PAGE_SIZE * (thread_stack_pages + 2), PROT_NONE,
+  void* thread_stack_allocation = mmap(nullptr, getpagesize() * (thread_stack_pages + 2), PROT_NONE,
                                        MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
   if (thread_stack_allocation == MAP_FAILED) {
     fatal_errno("failed to allocate debuggerd thread stack");
   }
 
-  char* stack = static_cast<char*>(thread_stack_allocation) + PAGE_SIZE;
-  if (mprotect(stack, PAGE_SIZE * thread_stack_pages, PROT_READ | PROT_WRITE) != 0) {
+  char* stack = static_cast<char*>(thread_stack_allocation) + getpagesize();
+  if (mprotect(stack, getpagesize() * thread_stack_pages, PROT_READ | PROT_WRITE) != 0) {
     fatal_errno("failed to mprotect debuggerd thread stack");
   }
 
   // Stack grows negatively, set it to the last byte in the page...
-  stack = (stack + thread_stack_pages * PAGE_SIZE - 1);
+  stack = (stack + thread_stack_pages * getpagesize() - 1);
   // and align it.
   stack -= 15;
   pseudothread_stack = stack;

debuggerd/libdebuggerd/scudo.cpp

@@ -22,6 +22,7 @@
 
 #include <android-base/macros.h>
 #include <bionic/macros.h>
+#include <unistd.h>
 
 #include "tombstone.pb.h"
 
@@ -54,21 +55,21 @@ ScudoCrashData::ScudoCrashData(unwindstack::Memory* process_memory,
   }
 
   untagged_fault_addr_ = process_info.untagged_fault_address;
-  uintptr_t fault_page = untagged_fault_addr_ & ~(PAGE_SIZE - 1);
+  uintptr_t fault_page = untagged_fault_addr_ & ~(getpagesize() - 1);
 
-  uintptr_t memory_begin = fault_page - PAGE_SIZE * 16;
+  uintptr_t memory_begin = fault_page - getpagesize() * 16;
   if (memory_begin > fault_page) {
     return;
   }
 
-  uintptr_t memory_end = fault_page + PAGE_SIZE * 16;
+  uintptr_t memory_end = fault_page + getpagesize() * 16;
   if (memory_end < fault_page) {
     return;
   }
 
   auto memory = std::make_unique<char[]>(memory_end - memory_begin);
-  for (auto i = memory_begin; i != memory_end; i += PAGE_SIZE) {
-    process_memory->ReadFully(i, memory.get() + i - memory_begin, PAGE_SIZE);
+  for (auto i = memory_begin; i != memory_end; i += getpagesize()) {
+    process_memory->ReadFully(i, memory.get() + i - memory_begin, getpagesize());
   }
 
   auto memory_tags = std::make_unique<char[]>((memory_end - memory_begin) / kTagGranuleSize);

fs_mgr/fs_mgr.cpp

@@ -613,7 +613,6 @@ static void tune_metadata_csum(const std::string& blk_device, const FstabEntry&
 
 // Read the primary superblock from an f2fs filesystem.  On failure return
 // false.  If it's not an f2fs filesystem, also set FS_STAT_INVALID_MAGIC.
-#define F2FS_BLKSIZE 4096
 #define F2FS_SUPER_OFFSET 1024
 static bool read_f2fs_superblock(const std::string& blk_device, int* fs_stat) {
     android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(blk_device.c_str(), O_RDONLY | O_CLOEXEC)));
@@ -628,7 +627,9 @@ static bool read_f2fs_superblock(const std::string& blk_device, int* fs_stat) {
         PERROR << "Can't read '" << blk_device << "' superblock1";
         return false;
     }
-    if (TEMP_FAILURE_RETRY(pread(fd, &sb2, sizeof(sb2), F2FS_BLKSIZE + F2FS_SUPER_OFFSET)) !=
+    // F2FS only supports block_size=page_size case. So, it is safe to call
+    // `getpagesize()` and use that as size of super block.
+    if (TEMP_FAILURE_RETRY(pread(fd, &sb2, sizeof(sb2), getpagesize() + F2FS_SUPER_OFFSET)) !=
         sizeof(sb2)) {
         PERROR << "Can't read '" << blk_device << "' superblock2";
         return false;
@@ -652,7 +653,7 @@ bool fs_mgr_is_f2fs(const std::string& blk_device) {
         return false;
     }
     if (sb == cpu_to_le32(F2FS_SUPER_MAGIC)) return true;
-    if (TEMP_FAILURE_RETRY(pread(fd, &sb, sizeof(sb), F2FS_BLKSIZE + F2FS_SUPER_OFFSET)) !=
+    if (TEMP_FAILURE_RETRY(pread(fd, &sb, sizeof(sb), getpagesize() + F2FS_SUPER_OFFSET)) !=
         sizeof(sb)) {
         return false;
     }

fs_mgr/fs_mgr_format.cpp

@@ -32,6 +32,7 @@
 #include <selinux/android.h>
 #include <selinux/label.h>
 #include <selinux/selinux.h>
+#include <string>
 
 #include "fs_mgr_priv.h"
 
@@ -68,6 +69,13 @@ static int format_ext4(const std::string& fs_blkdev, const std::string& fs_mnt_p
 
     /* Format the partition using the calculated length */
 
+    // EXT4 supports 4K block size on 16K page sizes. A 4K block
+    // size formatted EXT4 partition will mount fine on both 4K and 16K page
+    // size kernels.
+    // However, EXT4 does not support 16K block size on 4K systems.
+    // If we want the same userspace code to work on both 4k/16k kernels,
+    // using a hardcoded 4096 block size is a simple solution. Using
+    // getpagesize() here would work as well, but 4096 is simpler.
     std::string size_str = std::to_string(dev_sz / 4096);
 
     std::vector<const char*> mke2fs_args = {"/system/bin/mke2fs", "-t", "ext4", "-b", "4096"};
@@ -127,7 +135,7 @@ static int format_f2fs(const std::string& fs_blkdev, uint64_t dev_sz, bool needs
 
     /* Format the partition using the calculated length */
 
-    std::string size_str = std::to_string(dev_sz / 4096);
+    const auto size_str = std::to_string(dev_sz / getpagesize());
 
     std::vector<const char*> args = {"/system/bin/make_f2fs", "-g", "android"};
     if (needs_projid) {

fs_mgr/fs_mgr_overlayfs.cpp

@@ -939,7 +939,9 @@ bool MakeScratchFilesystem(const std::string& scratch_device) {
     auto command = ""s;
     if (!access(kMkF2fs.c_str(), X_OK) && fs_mgr_filesystem_available("f2fs")) {
         fs_type = "f2fs";
-        command = kMkF2fs + " -w 4096 -f -d1 -l" + android::base::Basename(kScratchMountPoint);
+        command = kMkF2fs + " -w ";
+        command += std::to_string(getpagesize());
+        command += " -f -d1 -l" + android::base::Basename(kScratchMountPoint);
     } else if (!access(kMkExt4.c_str(), X_OK) && fs_mgr_filesystem_available("ext4")) {
         fs_type = "ext4";
         command = kMkExt4 + " -F -b 4096 -t ext4 -m 0 -O has_journal -M " + kScratchMountPoint;