Refactor EncryptInplace.cpp

Refactor EncryptInplace.cpp to simplify and improve it a lot.  This is
everything that didn't fit into prior commits, including:

- Share a lot more code between ext4, f2fs, and full encryption.

- Improve the log messages.  Most importantly, don't spam the log with
  huge numbers of messages, and don't log errors in expected cases.
  Note: generate_f2fs_info() is still too noisy, but that's part of
  "system/extras", not vold, so this change doesn't change that.

- When possible, do 32K reads/writes for f2fs and for full encryption,
  not just for ext4.  This might improve performance.

- Take advantage of C++ functionality.

- Be more careful about edge cases.  E.g. if the calculation of the
  number of blocks to encrypt was wrong, don't set vold.encrypt_progress
  to > 99 until we're actually done.

The net change is over 200 lines removed.

Before-after comparison of log when enabling metadata encryption:

ext4 before:
    I vold    : Beginning inplace encryption, nr_sec: 16777216
    D vold    : cryptfs_enable_inplace(/dev/block/dm-8, /dev/block/by-name/userdata, 16777216, 0)
    D vold    : Opening/dev/block/by-name/userdata
    D vold    : Opening/dev/block/dm-8
    I vold    : Encrypting ext4 filesystem in place...
    [omitted 6387 log messages]
    I vold    : Encrypted to sector 822084608
    D vold    : cryptfs_enable_inplace_ext4 success
    I vold    : Inplace encryption complete

ext4 after:
    D vold    : encrypt_inplace(/dev/block/dm-8, /dev/block/by-name/userdata, 16777216, false)
    D vold    : ext4 filesystem has 64 block groups
    I vold    : Encrypting ext4 filesystem on /dev/block/by-name/userdata in-place via /dev/block/dm-8
    I vold    : 50327 blocks (206 MB) of 2097152 blocks are in-use
    D vold    : Encrypted 10000 of 50327 blocks
    D vold    : Encrypted 20000 of 50327 blocks
    D vold    : Encrypted 30000 of 50327 blocks
    D vold    : Encrypted 40000 of 50327 blocks
    D vold    : Encrypted 50000 of 50327 blocks
    D vold    : Encrypted 50327 of 50327 blocks
    I vold    : Successfully encrypted ext4 filesystem on /dev/block/by-name/userdata

f2fs before:
    I vold    : Beginning inplace encryption, nr_sec: 16777216
    D vold    : cryptfs_enable_inplace(/dev/block/dm-8, /dev/block/by-name/userdata, 16777216, 0)
    D vold    : Opening/dev/block/by-name/userdata
    D vold    : Opening/dev/block/dm-8
    E vold    : Reading ext4 extent caused an exception
    D vold    : cryptfs_enable_inplace_ext4()=-1
    [omitted logspam from f2fs_sparseblock]
    I vold    : Encrypting from block 0
    I vold    : Encrypted to block 15872
    I vold    : Encrypting from block 16384
    I vold    : Encrypted to block 16385
    I vold    : Encrypting from block 17408
    I vold    : Encrypted to block 17412
    D vold    : cryptfs_enable_inplace_f2fs success
    I vold    : Inplace encryption complete

f2fs after:
    D vold    : encrypt_inplace(/dev/block/dm-8, /dev/block/by-name/userdata, 16777216, false)
    [omitted logspam from f2fs_sparseblock]
    I vold    : Encrypting f2fs filesystem on /dev/block/by-name/userdata in-place via /dev/block/dm-8
    I vold    : 15880 blocks (65 MB) of 2097152 blocks are in-use
    D vold    : Encrypted 10000 of 15880 blocks
    D vold    : Encrypted 15880 of 15880 blocks
    I vold    : Successfully encrypted f2fs filesystem on /dev/block/by-name/userdata

Test: Booted Cuttlefish with metadata encryption enabled and with the
      userdata filesystem using (1) ext4, (2) f2fs, and (3) f2fs but
      with EncryptInplace.cpp patched to not recognize the filesystem
      and fall back to the "full" encryption case.  Checked that the log
      messages were as expected and that /data was mounted.

      I've had no luck testing FDE yet; it doesn't work even without
      these changes.  Suggestions appreciated...

Change-Id: I08fc8465f7962abd698904b5466f3ed080d53953
diff --git a/EncryptInplace.cpp b/EncryptInplace.cpp
index 471daef..8baed78 100644
--- a/EncryptInplace.cpp
+++ b/EncryptInplace.cpp
@@ -20,539 +20,356 @@
 #include <ext4_utils/ext4_utils.h>
 #include <f2fs_sparseblock.h>
 #include <fcntl.h>
-#include <inttypes.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <sys/stat.h>
-#include <sys/types.h>
 #include <time.h>
 
 #include <algorithm>
+#include <vector>
 
 #include <android-base/logging.h>
 #include <android-base/properties.h>
+#include <android-base/unique_fd.h>
 
-// FIXME horrible cut-and-paste code
-static inline int unix_read(int fd, void* buff, int len) {
-    return TEMP_FAILURE_RETRY(read(fd, buff, len));
-}
-
-static inline int unix_write(int fd, const void* buff, int len) {
-    return TEMP_FAILURE_RETRY(write(fd, buff, len));
-}
-
-#define CRYPT_SECTORS_PER_BUFSIZE (CRYPT_INPLACE_BUFSIZE / CRYPT_SECTOR_SIZE)
-
-/* aligned 32K writes tends to make flash happy.
- * SD card association recommends it.
- */
-#define BLOCKS_AT_A_TIME 8
-
-struct encryptGroupsData {
-    int realfd;
-    int cryptofd;
-    off64_t one_pct, cur_pct, new_pct;
-    off64_t blocks_already_done;
-    off64_t used_blocks_already_done, tot_used_blocks;
-    const char* real_blkdev;
-    const char* crypto_blkdev;
-    int count;
-    off64_t offset;
-    char* buffer;
-    time_t time_started;
-    int remaining_time;
-    bool set_progress_properties;
+enum EncryptInPlaceError {
+    kSuccess,
+    kFailed,
+    kFilesystemNotFound,
 };
 
-static void update_progress(struct encryptGroupsData* data, int is_used) {
-    data->blocks_already_done++;
+static uint64_t round_up(uint64_t val, size_t amount) {
+    if (val % amount) val += amount - (val % amount);
+    return val;
+}
 
-    if (is_used) {
-        data->used_blocks_already_done++;
-    }
-    if (data->tot_used_blocks) {
-        data->new_pct = data->used_blocks_already_done / data->one_pct;
+class InPlaceEncrypter {
+  public:
+    bool EncryptInPlace(const std::string& crypto_blkdev, const std::string& real_blkdev,
+                        uint64_t nr_sec, bool set_progress_properties);
+    bool ProcessUsedBlock(uint64_t block_num);
+
+  private:
+    // aligned 32K writes tends to make flash happy.
+    // SD card association recommends it.
+    static const size_t kIOBufferSize = 32768;
+
+    // Avoid spamming the logs.  Print the "Encrypting blocks" log message once
+    // every 10000 blocks (which is usually every 40 MB or so), and once at the end.
+    static const int kLogInterval = 10000;
+
+    std::string DescribeFilesystem();
+    void InitFs(const std::string& fs_type, uint64_t blocks_to_encrypt, uint64_t total_blocks,
+                unsigned int block_size);
+    void UpdateProgress(size_t blocks, bool done);
+    bool EncryptPendingData();
+    bool DoEncryptInPlace();
+
+    // ext4 methods
+    bool ReadExt4BlockBitmap(uint32_t group, uint8_t* buf);
+    uint64_t FirstBlockInGroup(uint32_t group);
+    uint32_t NumBlocksInGroup(uint32_t group);
+    uint32_t NumBaseMetaBlocksInGroup(uint64_t group);
+    EncryptInPlaceError EncryptInPlaceExt4();
+
+    // f2fs methods
+    EncryptInPlaceError EncryptInPlaceF2fs();
+
+    std::string real_blkdev_;
+    std::string crypto_blkdev_;
+    uint64_t nr_sec_;
+    bool set_progress_properties_;
+
+    android::base::unique_fd realfd_;
+    android::base::unique_fd cryptofd_;
+
+    time_t time_started_;
+    int remaining_time_;
+
+    std::string fs_type_;
+    uint64_t blocks_done_;
+    uint64_t blocks_to_encrypt_;
+    unsigned int block_size_;
+    unsigned int cur_pct_;
+
+    std::vector<uint8_t> io_buffer_;
+    uint64_t first_pending_block_;
+    size_t blocks_pending_;
+};
+
+std::string InPlaceEncrypter::DescribeFilesystem() {
+    if (fs_type_.empty())
+        return "full block device " + real_blkdev_;
+    else
+        return fs_type_ + " filesystem on " + real_blkdev_;
+}
+
+// Finishes initializing the encrypter, now that the filesystem details are known.
+void InPlaceEncrypter::InitFs(const std::string& fs_type, uint64_t blocks_to_encrypt,
+                              uint64_t total_blocks, unsigned int block_size) {
+    fs_type_ = fs_type;
+    blocks_done_ = 0;
+    blocks_to_encrypt_ = blocks_to_encrypt;
+    block_size_ = block_size;
+    cur_pct_ = 0;
+
+    // Allocate the I/O buffer.  kIOBufferSize should always be a multiple of
+    // the filesystem block size, but round it up just in case.
+    io_buffer_.resize(round_up(kIOBufferSize, block_size));
+    first_pending_block_ = 0;
+    blocks_pending_ = 0;
+
+    LOG(INFO) << "Encrypting " << DescribeFilesystem() << " in-place via " << crypto_blkdev_;
+    LOG(INFO) << blocks_to_encrypt << " blocks (" << (blocks_to_encrypt * block_size) / 1000000
+              << " MB) of " << total_blocks << " blocks are in-use";
+}
+
+void InPlaceEncrypter::UpdateProgress(size_t blocks, bool done) {
+    // A log message already got printed for blocks_done_ if one was due, so the
+    // next message will be due at the *next* block rounded up to kLogInterval.
+    uint64_t blocks_next_msg = round_up(blocks_done_ + 1, kLogInterval);
+
+    blocks_done_ += blocks;
+
+    // Ensure that a log message gets printed at the end, but not if one was
+    // already printed due to the block count being a multiple of kLogInterval.
+    // E.g. we want to show "50000 of 50327" and then "50327 of "50327", but not
+    // "50000 of 50000" and then redundantly "50000 of 50000" again.
+    if (done && blocks_done_ % kLogInterval != 0) blocks_next_msg = blocks_done_;
+
+    if (blocks_done_ >= blocks_next_msg)
+        LOG(DEBUG) << "Encrypted " << blocks_next_msg << " of " << blocks_to_encrypt_ << " blocks";
+
+    if (!set_progress_properties_) return;
+
+    uint64_t new_pct;
+    if (done) {
+        new_pct = 100;
     } else {
-        data->new_pct = data->blocks_already_done / data->one_pct;
+        new_pct = (blocks_done_ * 100) / std::max<uint64_t>(blocks_to_encrypt_, 1);
+        new_pct = std::min<uint64_t>(new_pct, 99);
+    }
+    if (new_pct > cur_pct_) {
+        cur_pct_ = new_pct;
+        android::base::SetProperty("vold.encrypt_progress", std::to_string(new_pct));
     }
 
-    if (!data->set_progress_properties) return;
-
-    if (data->new_pct > data->cur_pct) {
-        char buf[8];
-        data->cur_pct = data->new_pct;
-        snprintf(buf, sizeof(buf), "%" PRId64, data->cur_pct);
-        android::base::SetProperty("vold.encrypt_progress", buf);
-    }
-
-    if (data->cur_pct >= 5) {
+    if (cur_pct_ >= 5) {
         struct timespec time_now;
         if (clock_gettime(CLOCK_MONOTONIC, &time_now)) {
-            LOG(WARNING) << "Error getting time";
+            PLOG(WARNING) << "Error getting time while updating encryption progress";
         } else {
-            double elapsed_time = difftime(time_now.tv_sec, data->time_started);
-            off64_t remaining_blocks = data->tot_used_blocks - data->used_blocks_already_done;
-            int remaining_time =
-                (int)(elapsed_time * remaining_blocks / data->used_blocks_already_done);
+            double elapsed_time = difftime(time_now.tv_sec, time_started_);
+
+            uint64_t remaining_blocks = 0;
+            if (blocks_done_ < blocks_to_encrypt_)
+                remaining_blocks = blocks_to_encrypt_ - blocks_done_;
+
+            int remaining_time = 0;
+            if (blocks_done_ != 0)
+                remaining_time = (int)(elapsed_time * remaining_blocks / blocks_done_);
 
             // Change time only if not yet set, lower, or a lot higher for
             // best user experience
-            if (data->remaining_time == -1 || remaining_time < data->remaining_time ||
-                remaining_time > data->remaining_time + 60) {
-                char buf[8];
-                snprintf(buf, sizeof(buf), "%d", remaining_time);
-                android::base::SetProperty("vold.encrypt_time_remaining", buf);
-                data->remaining_time = remaining_time;
+            if (remaining_time_ == -1 || remaining_time < remaining_time_ ||
+                remaining_time > remaining_time_ + 60) {
+                remaining_time_ = remaining_time;
+                android::base::SetProperty("vold.encrypt_time_remaining",
+                                           std::to_string(remaining_time));
             }
         }
     }
 }
 
-static void log_progress(struct encryptGroupsData const* data, bool completed) {
-    // Precondition - if completed data = 0 else data != 0
+bool InPlaceEncrypter::EncryptPendingData() {
+    if (blocks_pending_ == 0) return true;
 
-    // Track progress so we can skip logging blocks
-    static off64_t offset = -1;
+    ssize_t bytes = blocks_pending_ * block_size_;
+    uint64_t offset = first_pending_block_ * block_size_;
 
-    // Need to close existing 'Encrypting from' log?
-    if (completed || (offset != -1 && data->offset != offset)) {
-        LOG(INFO) << "Encrypted to sector " << offset / info.block_size * CRYPT_SECTOR_SIZE;
-        offset = -1;
+    if (pread64(realfd_, &io_buffer_[0], bytes, offset) != bytes) {
+        PLOG(ERROR) << "Error reading real_blkdev " << real_blkdev_ << " for inplace encrypt";
+        return false;
     }
 
-    // Need to start new 'Encrypting from' log?
-    if (!completed && offset != data->offset) {
-        LOG(INFO) << "Encrypting from sector " << data->offset / info.block_size * CRYPT_SECTOR_SIZE;
+    if (pwrite64(cryptofd_, &io_buffer_[0], bytes, offset) != bytes) {
+        PLOG(ERROR) << "Error writing crypto_blkdev " << crypto_blkdev_ << " for inplace encrypt";
+        return false;
     }
 
-    // Update offset
-    if (!completed) {
-        offset = data->offset + (off64_t)data->count * info.block_size;
-    }
+    UpdateProgress(blocks_pending_, false);
+
+    blocks_pending_ = 0;
+    return true;
 }
 
-static int flush_outstanding_data(struct encryptGroupsData* data) {
-    if (data->count == 0) {
-        return 0;
+bool InPlaceEncrypter::ProcessUsedBlock(uint64_t block_num) {
+    // Flush if the amount of pending data has reached the I/O buffer size, if
+    // there's a gap between the pending blocks and the next block (due to
+    // block(s) not being used by the filesystem and thus not needing
+    // encryption), or if the next block will be aligned to the I/O buffer size.
+    if (blocks_pending_ * block_size_ == io_buffer_.size() ||
+        block_num != first_pending_block_ + blocks_pending_ ||
+        (block_num * block_size_) % io_buffer_.size() == 0) {
+        if (!EncryptPendingData()) return false;
+        first_pending_block_ = block_num;
     }
-
-    LOG(DEBUG) << "Copying " << data->count << " blocks at offset " << data->offset;
-
-    if (pread64(data->realfd, data->buffer, info.block_size * data->count, data->offset) <= 0) {
-        LOG(ERROR) << "Error reading real_blkdev " << data->real_blkdev << " for inplace encrypt";
-        return -1;
-    }
-
-    if (pwrite64(data->cryptofd, data->buffer, info.block_size * data->count, data->offset) <= 0) {
-        LOG(ERROR) << "Error writing crypto_blkdev " << data->crypto_blkdev
-                   << " for inplace encrypt";
-        return -1;
-    } else {
-        log_progress(data, false);
-    }
-
-    data->count = 0;
-    return 0;
+    blocks_pending_++;
+    return true;
 }
 
-static uint64_t first_block_in_group(uint32_t group) {
+// Reads the block bitmap for block group |group| into |buf|.
+bool InPlaceEncrypter::ReadExt4BlockBitmap(uint32_t group, uint8_t* buf) {
+    uint64_t offset = (uint64_t)aux_info.bg_desc[group].bg_block_bitmap * info.block_size;
+    if (pread64(realfd_, buf, info.block_size, offset) != (ssize_t)info.block_size) {
+        PLOG(ERROR) << "Failed to read block bitmap for block group " << group;
+        return false;
+    }
+    return true;
+}
+
+uint64_t InPlaceEncrypter::FirstBlockInGroup(uint32_t group) {
     return aux_info.first_data_block + (group * (uint64_t)info.blocks_per_group);
 }
 
-static uint32_t num_blocks_in_group(uint32_t group) {
-    uint64_t remaining = aux_info.len_blocks - first_block_in_group(group);
+uint32_t InPlaceEncrypter::NumBlocksInGroup(uint32_t group) {
+    uint64_t remaining = aux_info.len_blocks - FirstBlockInGroup(group);
     return std::min<uint64_t>(info.blocks_per_group, remaining);
 }
 
 // In block groups with an uninitialized block bitmap, we only need to encrypt
 // the backup superblock and the block group descriptors (if they are present).
-static uint32_t num_base_meta_blocks_in_group(uint64_t group) {
+uint32_t InPlaceEncrypter::NumBaseMetaBlocksInGroup(uint64_t group) {
     if (!ext4_bg_has_super_block(group)) return 0;
     return 1 + aux_info.bg_desc_blocks;
 }
 
-static int encrypt_groups(struct encryptGroupsData* data) {
-    unsigned int i;
-    u8* block_bitmap = 0;
-    unsigned int block;
-    off64_t ret;
-    int rc = -1;
+EncryptInPlaceError InPlaceEncrypter::EncryptInPlaceExt4() {
+    if (setjmp(setjmp_env))  // NOLINT
+        return kFilesystemNotFound;
 
-    data->buffer = (char*)malloc(info.block_size * BLOCKS_AT_A_TIME);
-    if (!data->buffer) {
-        LOG(ERROR) << "Failed to allocate crypto buffer";
-        goto errout;
-    }
+    if (read_ext(realfd_, 0) != 0) return kFilesystemNotFound;
 
-    block_bitmap = (u8*)malloc(info.block_size);
-    if (!block_bitmap) {
-        LOG(ERROR) << "failed to allocate block bitmap";
-        goto errout;
-    }
+    LOG(DEBUG) << "ext4 filesystem has " << aux_info.groups << " block groups";
 
-    for (i = 0; i < aux_info.groups; ++i) {
-        LOG(INFO) << "Encrypting group " << i;
-
-        u32 block_count = num_blocks_in_group(i);
-
-        off64_t offset = (u64)info.block_size * aux_info.bg_desc[i].bg_block_bitmap;
-
-        ret = pread64(data->realfd, block_bitmap, info.block_size, offset);
-        if (ret != (int)info.block_size) {
-            LOG(ERROR) << "failed to read all of block group bitmap " << i;
-            goto errout;
-        }
-
-        offset = (u64)info.block_size * first_block_in_group(i);
-
-        data->count = 0;
-
-        for (block = 0; block < block_count; block++) {
-            int used;
-
-            if (aux_info.bg_desc[i].bg_flags & EXT4_BG_BLOCK_UNINIT)
-                used = (block < num_base_meta_blocks_in_group(i));
-            else
-                used = bitmap_get_bit(block_bitmap, block);
-
-            update_progress(data, used);
-            if (used) {
-                if (data->count == 0) {
-                    data->offset = offset;
-                }
-                data->count++;
-            } else {
-                if (flush_outstanding_data(data)) {
-                    goto errout;
-                }
-            }
-
-            offset += info.block_size;
-
-            /* Write data if we are aligned or buffer size reached */
-            if (offset % (info.block_size * BLOCKS_AT_A_TIME) == 0 ||
-                data->count == BLOCKS_AT_A_TIME) {
-                if (flush_outstanding_data(data)) {
-                    goto errout;
-                }
-            }
-        }
-        if (flush_outstanding_data(data)) {
-            goto errout;
-        }
-    }
-
-    rc = 0;
-
-errout:
-    log_progress(0, true);
-    free(data->buffer);
-    free(block_bitmap);
-    return rc;
-}
-
-static int cryptfs_enable_inplace_ext4(const char* crypto_blkdev, const char* real_blkdev,
-                                       off64_t size, bool set_progress_properties) {
-    u32 i;
-    struct encryptGroupsData data;
-    int rc;  // Can't initialize without causing warning -Wclobbered
-    int retries = RETRY_MOUNT_ATTEMPTS;
-    struct timespec time_started = {0};
-
-    memset(&data, 0, sizeof(data));
-    data.real_blkdev = real_blkdev;
-    data.crypto_blkdev = crypto_blkdev;
-    data.set_progress_properties = set_progress_properties;
-
-    LOG(DEBUG) << "Opening" << real_blkdev;
-    if ((data.realfd = open(real_blkdev, O_RDWR | O_CLOEXEC)) < 0) {
-        PLOG(ERROR) << "Error opening real_blkdev " << real_blkdev << " for inplace encrypt";
-        rc = -1;
-        goto errout;
-    }
-
-    LOG(DEBUG) << "Opening" << crypto_blkdev;
-    if ((data.cryptofd = open(crypto_blkdev, O_WRONLY | O_CLOEXEC)) < 0) {
-        PLOG(ERROR) << "Error opening crypto_blkdev " << crypto_blkdev << " for inplace encrypt";
-        rc = -1;
-        goto errout;
-    }
-
-    if (setjmp(setjmp_env)) {  // NOLINT
-        LOG(ERROR) << "Reading ext4 extent caused an exception";
-        rc = -1;
-        goto errout;
-    }
-
-    if (read_ext(data.realfd, 0) != 0) {
-        LOG(ERROR) << "Failed to read ext4 extent";
-        rc = -1;
-        goto errout;
-    }
-
-    data.blocks_already_done = 0;
-
-    LOG(INFO) << "Encrypting ext4 filesystem in place...";
-
-    data.tot_used_blocks = 0;
-    for (i = 0; i < aux_info.groups; ++i) {
-        if (aux_info.bg_desc[i].bg_flags & EXT4_BG_BLOCK_UNINIT)
-            data.tot_used_blocks += num_base_meta_blocks_in_group(i);
+    uint64_t blocks_to_encrypt = 0;
+    for (uint32_t group = 0; group < aux_info.groups; group++) {
+        if (aux_info.bg_desc[group].bg_flags & EXT4_BG_BLOCK_UNINIT)
+            blocks_to_encrypt += NumBaseMetaBlocksInGroup(group);
         else
-            data.tot_used_blocks +=
-                    (num_blocks_in_group(i) - aux_info.bg_desc[i].bg_free_blocks_count);
+            blocks_to_encrypt +=
+                    (NumBlocksInGroup(group) - aux_info.bg_desc[group].bg_free_blocks_count);
     }
 
-    data.one_pct = data.tot_used_blocks / 100;
-    data.cur_pct = 0;
+    InitFs("ext4", blocks_to_encrypt, aux_info.len_blocks, info.block_size);
 
-    if (clock_gettime(CLOCK_MONOTONIC, &time_started)) {
-        LOG(WARNING) << "Error getting time at start";
-        // Note - continue anyway - we'll run with 0
+    // Encrypt each block group.
+    std::vector<uint8_t> block_bitmap(info.block_size);
+    for (uint32_t group = 0; group < aux_info.groups; group++) {
+        if (!ReadExt4BlockBitmap(group, &block_bitmap[0])) return kFailed;
+
+        uint64_t first_block_num = FirstBlockInGroup(group);
+        bool uninit = (aux_info.bg_desc[group].bg_flags & EXT4_BG_BLOCK_UNINIT);
+        uint32_t block_count = uninit ? NumBaseMetaBlocksInGroup(group) : NumBlocksInGroup(group);
+
+        // Encrypt each used block in the block group.
+        for (uint32_t i = 0; i < block_count; i++) {
+            if (uninit || bitmap_get_bit(&block_bitmap[0], i))
+                ProcessUsedBlock(first_block_num + i);
+        }
     }
-    data.time_started = time_started.tv_sec;
-    data.remaining_time = -1;
-
-    rc = encrypt_groups(&data);
-    if (rc) {
-        LOG(ERROR) << "Error encrypting groups";
-        goto errout;
-    }
-
-    rc = 0;
-
-errout:
-    close(data.realfd);
-    close(data.cryptofd);
-
-    return rc;
+    return kSuccess;
 }
 
-static void log_progress_f2fs(u64 block, bool completed) {
-    // Precondition - if completed data = 0 else data != 0
-
-    // Track progress so we can skip logging blocks
-    static u64 last_block = (u64)-1;
-
-    // Need to close existing 'Encrypting from' log?
-    if (completed || (last_block != (u64)-1 && block != last_block + 1)) {
-        LOG(INFO) << "Encrypted to block " << last_block;
-        last_block = -1;
-    }
-
-    // Need to start new 'Encrypting from' log?
-    if (!completed && (last_block == (u64)-1 || block != last_block + 1)) {
-        LOG(INFO) << "Encrypting from block " << block;
-    }
-
-    // Update offset
-    if (!completed) {
-        last_block = block;
-    }
-}
-
-static int encrypt_one_block_f2fs(u64 pos, void* data) {
-    struct encryptGroupsData* priv_dat = (struct encryptGroupsData*)data;
-
-    priv_dat->blocks_already_done = pos - 1;
-    update_progress(priv_dat, 1);
-
-    off64_t offset = pos * CRYPT_INPLACE_BUFSIZE;
-
-    if (pread64(priv_dat->realfd, priv_dat->buffer, CRYPT_INPLACE_BUFSIZE, offset) <= 0) {
-        LOG(ERROR) << "Error reading real_blkdev " << priv_dat->crypto_blkdev
-                   << " for f2fs inplace encrypt";
-        return -1;
-    }
-
-    if (pwrite64(priv_dat->cryptofd, priv_dat->buffer, CRYPT_INPLACE_BUFSIZE, offset) <= 0) {
-        LOG(ERROR) << "Error writing crypto_blkdev " << priv_dat->crypto_blkdev
-                   << " for f2fs inplace encrypt";
-        return -1;
-    } else {
-        log_progress_f2fs(pos, false);
-    }
-
+static int encrypt_f2fs_block(uint64_t block_num, void* _encrypter) {
+    InPlaceEncrypter* encrypter = reinterpret_cast<InPlaceEncrypter*>(_encrypter);
+    if (!encrypter->ProcessUsedBlock(block_num)) return -1;
     return 0;
 }
 
-static int cryptfs_enable_inplace_f2fs(const char* crypto_blkdev, const char* real_blkdev,
-                                       off64_t size, bool set_progress_properties) {
-    struct encryptGroupsData data;
-    struct f2fs_info* f2fs_info = NULL;
-    int rc = ENABLE_INPLACE_ERR_OTHER;
+EncryptInPlaceError InPlaceEncrypter::EncryptInPlaceF2fs() {
+    std::unique_ptr<struct f2fs_info, void (*)(struct f2fs_info*)> fs_info(
+            generate_f2fs_info(realfd_), free_f2fs_info);
+    if (!fs_info) return kFilesystemNotFound;
+
+    InitFs("f2fs", get_num_blocks_used(fs_info.get()), fs_info->total_blocks, fs_info->block_size);
+    if (run_on_used_blocks(0, fs_info.get(), encrypt_f2fs_block, this) != 0) return kFailed;
+    return kSuccess;
+}
+
+bool InPlaceEncrypter::DoEncryptInPlace() {
+    EncryptInPlaceError rc;
+
+    rc = EncryptInPlaceExt4();
+    if (rc != kFilesystemNotFound) return rc == kSuccess;
+
+    rc = EncryptInPlaceF2fs();
+    if (rc != kFilesystemNotFound) return rc == kSuccess;
+
+    LOG(WARNING) << "No recognized filesystem found on " << real_blkdev_
+                 << ".  Falling back to encrypting the full block device.";
+    InitFs("", nr_sec_, nr_sec_, 512);
+    for (uint64_t i = 0; i < nr_sec_; i++) {
+        if (!ProcessUsedBlock(i)) return false;
+    }
+    return true;
+}
+
+bool InPlaceEncrypter::EncryptInPlace(const std::string& crypto_blkdev,
+                                      const std::string& real_blkdev, uint64_t nr_sec,
+                                      bool set_progress_properties) {
     struct timespec time_started = {0};
 
-    memset(&data, 0, sizeof(data));
-    data.real_blkdev = real_blkdev;
-    data.crypto_blkdev = crypto_blkdev;
-    data.set_progress_properties = set_progress_properties;
-    data.realfd = -1;
-    data.cryptofd = -1;
-    if ((data.realfd = open64(real_blkdev, O_RDWR | O_CLOEXEC)) < 0) {
-        PLOG(ERROR) << "Error opening real_blkdev " << real_blkdev << " for f2fs inplace encrypt";
-        goto errout;
-    }
-    if ((data.cryptofd = open64(crypto_blkdev, O_WRONLY | O_CLOEXEC)) < 0) {
-        PLOG(ERROR) << "Error opening crypto_blkdev " << crypto_blkdev
-                    << " for f2fs inplace encrypt";
-        goto errout;
+    real_blkdev_ = real_blkdev;
+    crypto_blkdev_ = crypto_blkdev;
+    nr_sec_ = nr_sec;
+    set_progress_properties_ = set_progress_properties;
+
+    realfd_.reset(open64(real_blkdev.c_str(), O_RDONLY | O_CLOEXEC));
+    if (realfd_ < 0) {
+        PLOG(ERROR) << "Error opening real_blkdev " << real_blkdev << " for inplace encrypt";
+        return false;
     }
 
-    f2fs_info = generate_f2fs_info(data.realfd);
-    if (!f2fs_info) goto errout;
+    cryptofd_.reset(open64(crypto_blkdev.c_str(), O_WRONLY | O_CLOEXEC));
+    if (cryptofd_ < 0) {
+        PLOG(ERROR) << "Error opening crypto_blkdev " << crypto_blkdev << " for inplace encrypt";
+        return false;
+    }
 
-    data.blocks_already_done = 0;
-
-    data.tot_used_blocks = get_num_blocks_used(f2fs_info);
-
-    data.one_pct = data.tot_used_blocks / 100;
-    data.cur_pct = 0;
     if (clock_gettime(CLOCK_MONOTONIC, &time_started)) {
-        LOG(WARNING) << "Error getting time at start";
+        PLOG(WARNING) << "Error getting time at start of in-place encryption";
         // Note - continue anyway - we'll run with 0
     }
-    data.time_started = time_started.tv_sec;
-    data.remaining_time = -1;
+    time_started_ = time_started.tv_sec;
+    remaining_time_ = -1;
 
+    bool success = DoEncryptInPlace();
 
-    data.buffer = (char*)malloc(f2fs_info->block_size);
-    if (!data.buffer) {
-        LOG(ERROR) << "Failed to allocate crypto buffer";
-        goto errout;
+    if (success) success &= EncryptPendingData();
+
+    if (!success) {
+        LOG(ERROR) << "In-place encryption of " << DescribeFilesystem() << " failed";
+        return false;
     }
-
-    data.count = 0;
-
-    /* Currently, this either runs to completion, or hits a nonrecoverable error */
-    rc = run_on_used_blocks(data.blocks_already_done, f2fs_info, &encrypt_one_block_f2fs, &data);
-
-    if (rc) {
-        LOG(ERROR) << "Error in running over f2fs blocks";
-        rc = ENABLE_INPLACE_ERR_OTHER;
-        goto errout;
+    if (blocks_done_ != blocks_to_encrypt_) {
+        LOG(WARNING) << "blocks_to_encrypt (" << blocks_to_encrypt_
+                     << ") was incorrect; we actually encrypted " << blocks_done_
+                     << " blocks.  Encryption progress was inaccurate";
     }
-
-    rc = 0;
-
-errout:
-    if (rc) LOG(ERROR) << "Failed to encrypt f2fs filesystem on " << real_blkdev;
-
-    log_progress_f2fs(0, true);
-    free_f2fs_info(f2fs_info);
-    free(data.buffer);
-    close(data.realfd);
-    close(data.cryptofd);
-
-    return rc;
+    // Make sure vold.encrypt_progress gets set to 100.
+    UpdateProgress(0, true);
+    LOG(INFO) << "Successfully encrypted " << DescribeFilesystem();
+    return true;
 }
 
-static int cryptfs_enable_inplace_full(const char* crypto_blkdev, const char* real_blkdev,
-                                       off64_t size, bool set_progress_properties) {
-    int realfd, cryptofd;
-    char* buf[CRYPT_INPLACE_BUFSIZE];
-    int rc = ENABLE_INPLACE_ERR_OTHER;
-    off64_t numblocks, i, remainder;
-    off64_t one_pct, cur_pct, new_pct;
+// Encrypts |real_blkdev| in-place by reading the data from |real_blkdev| and
+// writing it to |crypto_blkdev|, which should be a dm-crypt or dm-default-key
+// device backed by |real_blkdev|.  The size to encrypt is |nr_sec| 512-byte
+// sectors; however, if a filesystem is detected, then its size will be used
+// instead, and only the in-use blocks of the filesystem will be encrypted.
+bool encrypt_inplace(const std::string& crypto_blkdev, const std::string& real_blkdev,
+                     uint64_t nr_sec, bool set_progress_properties) {
+    LOG(DEBUG) << "encrypt_inplace(" << crypto_blkdev << ", " << real_blkdev << ", " << nr_sec
+               << ", " << (set_progress_properties ? "true" : "false") << ")";
 
-    if ((realfd = open(real_blkdev, O_RDONLY | O_CLOEXEC)) < 0) {
-        PLOG(ERROR) << "Error opening real_blkdev " << real_blkdev << " for inplace encrypt";
-        return ENABLE_INPLACE_ERR_OTHER;
-    }
-
-    if ((cryptofd = open(crypto_blkdev, O_WRONLY | O_CLOEXEC)) < 0) {
-        PLOG(ERROR) << "Error opening crypto_blkdev " << crypto_blkdev << " for inplace encrypt";
-        close(realfd);
-        return ENABLE_INPLACE_ERR_OTHER;
-    }
-
-    /* This is pretty much a simple loop of reading 4K, and writing 4K.
-     * The size passed in is the number of 512 byte sectors in the filesystem.
-     * So compute the number of whole 4K blocks we should read/write,
-     * and the remainder.
-     */
-    numblocks = size / CRYPT_SECTORS_PER_BUFSIZE;
-    remainder = size % CRYPT_SECTORS_PER_BUFSIZE;
-
-    LOG(ERROR) << "Encrypting filesystem in place...";
-
-    one_pct = numblocks / 100;
-    cur_pct = 0;
-    /* process the majority of the filesystem in blocks */
-    for (i = 0; i < numblocks; i++) {
-        new_pct = i / one_pct;
-        if (set_progress_properties && new_pct > cur_pct) {
-            char property_buf[8];
-
-            cur_pct = new_pct;
-            snprintf(property_buf, sizeof(property_buf), "%" PRId64, cur_pct);
-            android::base::SetProperty("vold.encrypt_progress", property_buf);
-        }
-        if (unix_read(realfd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) {
-            PLOG(ERROR) << "Error reading real_blkdev " << real_blkdev << " for inplace encrypt";
-            goto errout;
-        }
-        if (unix_write(cryptofd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) {
-            PLOG(ERROR) << "Error writing crypto_blkdev " << crypto_blkdev << " for inplace encrypt";
-            goto errout;
-        } else {
-            LOG(DEBUG) << "Encrypted " << CRYPT_SECTORS_PER_BUFSIZE << " block at "
-                       << i * CRYPT_SECTORS_PER_BUFSIZE;
-        }
-    }
-
-    /* Do any remaining sectors */
-    for (i = 0; i < remainder; i++) {
-        if (unix_read(realfd, buf, CRYPT_SECTOR_SIZE) <= 0) {
-            LOG(ERROR) << "Error reading final sectors from real_blkdev " << real_blkdev
-                       << " for inplace encrypt";
-            goto errout;
-        }
-        if (unix_write(cryptofd, buf, CRYPT_SECTOR_SIZE) <= 0) {
-            LOG(ERROR) << "Error writing final sectors to crypto_blkdev " << crypto_blkdev
-                       << " for inplace encrypt";
-            goto errout;
-        } else {
-            LOG(INFO) << "Encrypted 1 block at next location";
-        }
-    }
-
-    rc = 0;
-
-errout:
-    close(realfd);
-    close(cryptofd);
-
-    return rc;
-}
-
-/* returns on of the ENABLE_INPLACE_* return codes */
-int cryptfs_enable_inplace(const char* crypto_blkdev, const char* real_blkdev, off64_t size,
-                           bool set_progress_properties) {
-    int rc_ext4, rc_f2fs, rc_full;
-    LOG(DEBUG) << "cryptfs_enable_inplace(" << crypto_blkdev << ", " << real_blkdev << ", " << size
-               << ", " << set_progress_properties << ")";
-
-    /* TODO: identify filesystem type.
-     * As is, cryptfs_enable_inplace_ext4 will fail on an f2fs partition, and
-     * then we will drop down to cryptfs_enable_inplace_f2fs.
-     * */
-    if ((rc_ext4 = cryptfs_enable_inplace_ext4(crypto_blkdev, real_blkdev, size,
-                                               set_progress_properties)) == 0) {
-        LOG(DEBUG) << "cryptfs_enable_inplace_ext4 success";
-        return 0;
-    }
-    LOG(DEBUG) << "cryptfs_enable_inplace_ext4()=" << rc_ext4;
-
-    if ((rc_f2fs = cryptfs_enable_inplace_f2fs(crypto_blkdev, real_blkdev, size,
-                                               set_progress_properties)) == 0) {
-        LOG(DEBUG) << "cryptfs_enable_inplace_f2fs success";
-        return 0;
-    }
-    LOG(DEBUG) << "cryptfs_enable_inplace_f2fs()=" << rc_f2fs;
-
-    rc_full =
-            cryptfs_enable_inplace_full(crypto_blkdev, real_blkdev, size, set_progress_properties);
-    LOG(DEBUG) << "cryptfs_enable_inplace_full()=" << rc_full;
-    return rc_full;
+    InPlaceEncrypter encrypter;
+    return encrypter.EncryptInPlace(crypto_blkdev, real_blkdev, nr_sec, set_progress_properties);
 }