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platform_system_core
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Merge "libfiemap: Fix fallocate() usage."

This commit is contained in:
David Anderson 2019-12-18 15:37:10 +00:00 committed by Gerrit Code Review
parent 90e9217aca 71b287bfd7
commit 42c86c763c
1 changed files with 50 additions and 37 deletions
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87
fs_mgr/libfiemap/fiemap_writer.cpp
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@ -386,43 +386,12 @@ static bool PinFile(int file_fd, const std::string& file_path, uint32_t fs_type)
return true;
}
// Reserve space for the file on the file system and write it out to make sure the extents
// don't come back unwritten. Return from this function with the kernel file offset set to 0.
// If the filesystem is f2fs, then we also PIN the file on disk to make sure the blocks
// aren't moved around.
static bool AllocateFile(int file_fd, const std::string& file_path, uint64_t blocksz,
uint64_t file_size, unsigned int fs_type,
std::function<bool(uint64_t, uint64_t)> on_progress) {
switch (fs_type) {
case EXT4_SUPER_MAGIC:
break;
case F2FS_SUPER_MAGIC: {
bool supported;
if (!F2fsPinBeforeAllocate(file_fd, &supported)) {
return false;
}
if (supported && !PinFile(file_fd, file_path, fs_type)) {
return false;
}
break;
}
case MSDOS_SUPER_MAGIC:
// fallocate() is not supported, and not needed, since VFAT does not support holes.
// Instead we can perform a much faster allocation.
return FallocateFallback(file_fd, blocksz, file_size, file_path, on_progress);
default:
LOG(ERROR) << "Missing fallocate() support for file system " << fs_type;
return false;
}
if (fallocate(file_fd, FALLOC_FL_ZERO_RANGE, 0, file_size)) {
PLOG(ERROR) << "Failed to allocate space for file: " << file_path << " size: " << file_size;
return false;
}
// write zeroes in 'blocksz' byte increments until we reach file_size to make sure the data
// blocks are actually written to by the file system and thus getting rid of the holes in the
// file.
// write zeroes in 'blocksz' byte increments until we reach file_size to make sure the data
// blocks are actually written to by the file system and thus getting rid of the holes in the
// file.
static bool WriteZeroes(int file_fd, const std::string& file_path, size_t blocksz,
uint64_t file_size,
const std::function<bool(uint64_t, uint64_t)>& on_progress) {
auto buffer = std::unique_ptr<void, decltype(&free)>(calloc(1, blocksz), free);
if (buffer == nullptr) {
LOG(ERROR) << "failed to allocate memory for writing file";
@ -460,6 +429,50 @@ static bool AllocateFile(int file_fd, const std::string& file_path, uint64_t blo
PLOG(ERROR) << "Failed to reset offset at the beginning of : " << file_path;
return false;
}
return true;
}
// Reserve space for the file on the file system and write it out to make sure the extents
// don't come back unwritten. Return from this function with the kernel file offset set to 0.
// If the filesystem is f2fs, then we also PIN the file on disk to make sure the blocks
// aren't moved around.
static bool AllocateFile(int file_fd, const std::string& file_path, uint64_t blocksz,
uint64_t file_size, unsigned int fs_type,
std::function<bool(uint64_t, uint64_t)> on_progress) {
bool need_explicit_writes = true;
switch (fs_type) {
case EXT4_SUPER_MAGIC:
break;
case F2FS_SUPER_MAGIC: {
bool supported;
if (!F2fsPinBeforeAllocate(file_fd, &supported)) {
return false;
}
if (supported) {
if (!PinFile(file_fd, file_path, fs_type)) {
return false;
}
need_explicit_writes = false;
}
break;
}
case MSDOS_SUPER_MAGIC:
// fallocate() is not supported, and not needed, since VFAT does not support holes.
// Instead we can perform a much faster allocation.
return FallocateFallback(file_fd, blocksz, file_size, file_path, on_progress);
default:
LOG(ERROR) << "Missing fallocate() support for file system " << fs_type;
return false;
}
if (fallocate(file_fd, 0, 0, file_size)) {
PLOG(ERROR) << "Failed to allocate space for file: " << file_path << " size: " << file_size;
return false;
}
if (need_explicit_writes && !WriteZeroes(file_fd, file_path, blocksz, file_size, on_progress)) {
return false;
}
// flush all writes here ..
if (fsync(file_fd)) {