diff --git a/EncryptInplace.cpp b/EncryptInplace.cpp
new file mode 100644
index 0000000..9aa2a21
--- /dev/null
+++ b/EncryptInplace.cpp
@@ -0,0 +1,656 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "EncryptInplace.h"
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <inttypes.h>
+#include <time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <ext4_utils/ext4.h>
+#include <ext4_utils/ext4_utils.h>
+#include <f2fs_sparseblock.h>
+
+#include <algorithm>
+
+#include "cutils/properties.h"
+#define LOG_TAG "EncryptInplace"
+#include "cutils/log.h"
+#include "CheckBattery.h"
+
+// HORRIBLE HACK, FIXME
+#include "cryptfs.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.
+ */
+#ifndef CONFIG_HW_DISK_ENCRYPTION
+#define BLOCKS_AT_A_TIME 8
+#else
+#define BLOCKS_AT_A_TIME 1024
+#endif
+
+struct encryptGroupsData
+{
+    int realfd;
+    int cryptofd;
+    off64_t numblocks;
+    off64_t one_pct, cur_pct, new_pct;
+    off64_t blocks_already_done, tot_numblocks;
+    off64_t used_blocks_already_done, tot_used_blocks;
+    char* real_blkdev, * crypto_blkdev;
+    int count;
+    off64_t offset;
+    char* buffer;
+    off64_t last_written_sector;
+    int completed;
+    time_t time_started;
+    int remaining_time;
+};
+
+static void update_progress(struct encryptGroupsData* data, int is_used)
+{
+    data->blocks_already_done++;
+
+    if (is_used) {
+        data->used_blocks_already_done++;
+    }
+    if (data->tot_used_blocks) {
+        data->new_pct = data->used_blocks_already_done / data->one_pct;
+    } else {
+        data->new_pct = data->blocks_already_done / data->one_pct;
+    }
+
+    if (data->new_pct > data->cur_pct) {
+        char buf[8];
+        data->cur_pct = data->new_pct;
+        snprintf(buf, sizeof(buf), "%" PRId64, data->cur_pct);
+        property_set("vold.encrypt_progress", buf);
+    }
+
+    if (data->cur_pct >= 5) {
+        struct timespec time_now;
+        if (clock_gettime(CLOCK_MONOTONIC, &time_now)) {
+            SLOGW("Error getting time");
+        } 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);
+
+            // 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);
+                property_set("vold.encrypt_time_remaining", buf);
+                data->remaining_time = remaining_time;
+            }
+        }
+    }
+}
+
+static void log_progress(struct encryptGroupsData const* data, bool completed)
+{
+    // Precondition - if completed data = 0 else data != 0
+
+    // Track progress so we can skip logging blocks
+    static off64_t offset = -1;
+
+    // Need to close existing 'Encrypting from' log?
+    if (completed || (offset != -1 && data->offset != offset)) {
+        SLOGI("Encrypted to sector %" PRId64,
+              offset / info.block_size * CRYPT_SECTOR_SIZE);
+        offset = -1;
+    }
+
+    // Need to start new 'Encrypting from' log?
+    if (!completed && offset != data->offset) {
+        SLOGI("Encrypting from sector %" PRId64,
+              data->offset / info.block_size * CRYPT_SECTOR_SIZE);
+    }
+
+    // Update offset
+    if (!completed) {
+        offset = data->offset + (off64_t)data->count * info.block_size;
+    }
+}
+
+static int flush_outstanding_data(struct encryptGroupsData* data)
+{
+    if (data->count == 0) {
+        return 0;
+    }
+
+    SLOGV("Copying %d blocks at offset %" PRIx64, data->count, data->offset);
+
+    if (pread64(data->realfd, data->buffer,
+                info.block_size * data->count, data->offset)
+        <= 0) {
+        SLOGE("Error reading real_blkdev %s for inplace encrypt",
+              data->real_blkdev);
+        return -1;
+    }
+
+    if (pwrite64(data->cryptofd, data->buffer,
+                 info.block_size * data->count, data->offset)
+        <= 0) {
+        SLOGE("Error writing crypto_blkdev %s for inplace encrypt",
+              data->crypto_blkdev);
+        return -1;
+    } else {
+      log_progress(data, false);
+    }
+
+    data->count = 0;
+    data->last_written_sector = (data->offset + data->count)
+                                / info.block_size * CRYPT_SECTOR_SIZE - 1;
+    return 0;
+}
+
+static int encrypt_groups(struct encryptGroupsData* data)
+{
+    unsigned int i;
+    u8 *block_bitmap = 0;
+    unsigned int block;
+    off64_t ret;
+    int rc = -1;
+
+    data->buffer = (char*) malloc(info.block_size * BLOCKS_AT_A_TIME);
+    if (!data->buffer) {
+        SLOGE("Failed to allocate crypto buffer");
+        goto errout;
+    }
+
+    block_bitmap = (u8*) malloc(info.block_size);
+    if (!block_bitmap) {
+        SLOGE("failed to allocate block bitmap");
+        goto errout;
+    }
+
+    for (i = 0; i < aux_info.groups; ++i) {
+        SLOGI("Encrypting group %d", i);
+
+        u32 first_block = aux_info.first_data_block + i * info.blocks_per_group;
+        u32 block_count = std::min(info.blocks_per_group,
+                             (u32)(aux_info.len_blocks - first_block));
+
+        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) {
+            SLOGE("failed to read all of block group bitmap %d", i);
+            goto errout;
+        }
+
+        offset = (u64)info.block_size * first_block;
+
+        data->count = 0;
+
+        for (block = 0; block < block_count; block++) {
+            int used = (aux_info.bg_desc[i].bg_flags & EXT4_BG_BLOCK_UNINIT) ?
+                    0 : 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 (!is_battery_ok_to_continue()) {
+                SLOGE("Stopping encryption due to low battery");
+                rc = 0;
+                goto errout;
+            }
+
+        }
+        if (flush_outstanding_data(data)) {
+            goto errout;
+        }
+    }
+
+    data->completed = 1;
+    rc = 0;
+
+errout:
+    log_progress(0, true);
+    free(data->buffer);
+    free(block_bitmap);
+    return rc;
+}
+
+static int cryptfs_enable_inplace_ext4(char *crypto_blkdev,
+                                       char *real_blkdev,
+                                       off64_t size,
+                                       off64_t *size_already_done,
+                                       off64_t tot_size,
+                                       off64_t previously_encrypted_upto)
+{
+    u32 i;
+    struct encryptGroupsData data;
+    int rc; // Can't initialize without causing warning -Wclobbered
+    int retries = RETRY_MOUNT_ATTEMPTS;
+    struct timespec time_started = {0};
+
+    if (previously_encrypted_upto > *size_already_done) {
+        SLOGD("Not fast encrypting since resuming part way through");
+        return -1;
+    }
+
+    memset(&data, 0, sizeof(data));
+    data.real_blkdev = real_blkdev;
+    data.crypto_blkdev = crypto_blkdev;
+
+    if ( (data.realfd = open(real_blkdev, O_RDWR|O_CLOEXEC)) < 0) {
+        SLOGE("Error opening real_blkdev %s for inplace encrypt. err=%d(%s)\n",
+              real_blkdev, errno, strerror(errno));
+        rc = -1;
+        goto errout;
+    }
+
+    // Wait until the block device appears.  Re-use the mount retry values since it is reasonable.
+    while ((data.cryptofd = open(crypto_blkdev, O_WRONLY|O_CLOEXEC)) < 0) {
+        if (--retries) {
+            SLOGE("Error opening crypto_blkdev %s for ext4 inplace encrypt. err=%d(%s), retrying\n",
+                  crypto_blkdev, errno, strerror(errno));
+            sleep(RETRY_MOUNT_DELAY_SECONDS);
+        } else {
+            SLOGE("Error opening crypto_blkdev %s for ext4 inplace encrypt. err=%d(%s)\n",
+                  crypto_blkdev, errno, strerror(errno));
+            rc = ENABLE_INPLACE_ERR_DEV;
+            goto errout;
+        }
+    }
+
+    if (setjmp(setjmp_env)) { // NOLINT
+        SLOGE("Reading ext4 extent caused an exception\n");
+        rc = -1;
+        goto errout;
+    }
+
+    if (read_ext(data.realfd, 0) != 0) {
+        SLOGE("Failed to read ext4 extent\n");
+        rc = -1;
+        goto errout;
+    }
+
+    data.numblocks = size / CRYPT_SECTORS_PER_BUFSIZE;
+    data.tot_numblocks = tot_size / CRYPT_SECTORS_PER_BUFSIZE;
+    data.blocks_already_done = *size_already_done / CRYPT_SECTORS_PER_BUFSIZE;
+
+    SLOGI("Encrypting ext4 filesystem in place...");
+
+    data.tot_used_blocks = data.numblocks;
+    for (i = 0; i < aux_info.groups; ++i) {
+      data.tot_used_blocks -= aux_info.bg_desc[i].bg_free_blocks_count;
+    }
+
+    data.one_pct = data.tot_used_blocks / 100;
+    data.cur_pct = 0;
+
+    if (clock_gettime(CLOCK_MONOTONIC, &time_started)) {
+        SLOGW("Error getting time at start");
+        // Note - continue anyway - we'll run with 0
+    }
+    data.time_started = time_started.tv_sec;
+    data.remaining_time = -1;
+
+    rc = encrypt_groups(&data);
+    if (rc) {
+        SLOGE("Error encrypting groups");
+        goto errout;
+    }
+
+    *size_already_done += data.completed ? size : data.last_written_sector;
+    rc = 0;
+
+errout:
+    close(data.realfd);
+    close(data.cryptofd);
+
+    return rc;
+}
+
+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)) {
+        SLOGI("Encrypted to block %" PRId64, last_block);
+        last_block = -1;
+    }
+
+    // Need to start new 'Encrypting from' log?
+    if (!completed && (last_block == (u64)-1 || block != last_block + 1)) {
+        SLOGI("Encrypting from block %" PRId64, 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) {
+        SLOGE("Error reading real_blkdev %s for f2fs inplace encrypt", priv_dat->crypto_blkdev);
+        return -1;
+    }
+
+    if (pwrite64(priv_dat->cryptofd, priv_dat->buffer, CRYPT_INPLACE_BUFSIZE, offset) <= 0) {
+        SLOGE("Error writing crypto_blkdev %s for f2fs inplace encrypt", priv_dat->crypto_blkdev);
+        return -1;
+    } else {
+        log_progress_f2fs(pos, false);
+    }
+
+    return 0;
+}
+
+static int cryptfs_enable_inplace_f2fs(char *crypto_blkdev,
+                                       char *real_blkdev,
+                                       off64_t size,
+                                       off64_t *size_already_done,
+                                       off64_t tot_size,
+                                       off64_t previously_encrypted_upto)
+{
+    struct encryptGroupsData data;
+    struct f2fs_info *f2fs_info = NULL;
+    int rc = ENABLE_INPLACE_ERR_OTHER;
+    if (previously_encrypted_upto > *size_already_done) {
+        SLOGD("Not fast encrypting since resuming part way through");
+        return ENABLE_INPLACE_ERR_OTHER;
+    }
+    memset(&data, 0, sizeof(data));
+    data.real_blkdev = real_blkdev;
+    data.crypto_blkdev = crypto_blkdev;
+    data.realfd = -1;
+    data.cryptofd = -1;
+    if ( (data.realfd = open64(real_blkdev, O_RDWR|O_CLOEXEC)) < 0) {
+        SLOGE("Error opening real_blkdev %s for f2fs inplace encrypt\n",
+              real_blkdev);
+        goto errout;
+    }
+    if ( (data.cryptofd = open64(crypto_blkdev, O_WRONLY|O_CLOEXEC)) < 0) {
+        SLOGE("Error opening crypto_blkdev %s for f2fs inplace encrypt. err=%d(%s)\n",
+              crypto_blkdev, errno, strerror(errno));
+        rc = ENABLE_INPLACE_ERR_DEV;
+        goto errout;
+    }
+
+    f2fs_info = generate_f2fs_info(data.realfd);
+    if (!f2fs_info)
+      goto errout;
+
+    data.numblocks = size / CRYPT_SECTORS_PER_BUFSIZE;
+    data.tot_numblocks = tot_size / CRYPT_SECTORS_PER_BUFSIZE;
+    data.blocks_already_done = *size_already_done / CRYPT_SECTORS_PER_BUFSIZE;
+
+    data.tot_used_blocks = get_num_blocks_used(f2fs_info);
+
+    data.one_pct = data.tot_used_blocks / 100;
+    data.cur_pct = 0;
+    data.time_started = time(NULL);
+    data.remaining_time = -1;
+
+    data.buffer = (char*) malloc(f2fs_info->block_size);
+    if (!data.buffer) {
+        SLOGE("Failed to allocate crypto buffer");
+        goto errout;
+    }
+
+    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) {
+        SLOGE("Error in running over f2fs blocks");
+        rc = ENABLE_INPLACE_ERR_OTHER;
+        goto errout;
+    }
+
+    *size_already_done += size;
+    rc = 0;
+
+errout:
+    if (rc)
+        SLOGE("Failed to encrypt f2fs filesystem on %s", real_blkdev);
+
+    log_progress_f2fs(0, true);
+    free(f2fs_info);
+    free(data.buffer);
+    close(data.realfd);
+    close(data.cryptofd);
+
+    return rc;
+}
+
+static int cryptfs_enable_inplace_full(char *crypto_blkdev, char *real_blkdev,
+                                       off64_t size, off64_t *size_already_done,
+                                       off64_t tot_size,
+                                       off64_t previously_encrypted_upto)
+{
+    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;
+    off64_t blocks_already_done, tot_numblocks;
+
+    if ( (realfd = open(real_blkdev, O_RDONLY|O_CLOEXEC)) < 0) {
+        SLOGE("Error opening real_blkdev %s for inplace encrypt\n", real_blkdev);
+        return ENABLE_INPLACE_ERR_OTHER;
+    }
+
+    if ( (cryptofd = open(crypto_blkdev, O_WRONLY|O_CLOEXEC)) < 0) {
+        SLOGE("Error opening crypto_blkdev %s for inplace encrypt. err=%d(%s)\n",
+              crypto_blkdev, errno, strerror(errno));
+        close(realfd);
+        return ENABLE_INPLACE_ERR_DEV;
+    }
+
+    /* 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;
+    tot_numblocks = tot_size / CRYPT_SECTORS_PER_BUFSIZE;
+    blocks_already_done = *size_already_done / CRYPT_SECTORS_PER_BUFSIZE;
+
+    SLOGE("Encrypting filesystem in place...");
+
+    i = previously_encrypted_upto + 1 - *size_already_done;
+
+    if (lseek64(realfd, i * CRYPT_SECTOR_SIZE, SEEK_SET) < 0) {
+        SLOGE("Cannot seek to previously encrypted point on %s", real_blkdev);
+        goto errout;
+    }
+
+    if (lseek64(cryptofd, i * CRYPT_SECTOR_SIZE, SEEK_SET) < 0) {
+        SLOGE("Cannot seek to previously encrypted point on %s", crypto_blkdev);
+        goto errout;
+    }
+
+    for (;i < size && i % CRYPT_SECTORS_PER_BUFSIZE != 0; ++i) {
+        if (unix_read(realfd, buf, CRYPT_SECTOR_SIZE) <= 0) {
+            SLOGE("Error reading initial sectors from real_blkdev %s for "
+                  "inplace encrypt\n", crypto_blkdev);
+            goto errout;
+        }
+        if (unix_write(cryptofd, buf, CRYPT_SECTOR_SIZE) <= 0) {
+            SLOGE("Error writing initial sectors to crypto_blkdev %s for "
+                  "inplace encrypt\n", crypto_blkdev);
+            goto errout;
+        } else {
+            SLOGI("Encrypted 1 block at %" PRId64, i);
+        }
+    }
+
+    one_pct = tot_numblocks / 100;
+    cur_pct = 0;
+    /* process the majority of the filesystem in blocks */
+    for (i/=CRYPT_SECTORS_PER_BUFSIZE; i<numblocks; i++) {
+        new_pct = (i + blocks_already_done) / one_pct;
+        if (new_pct > cur_pct) {
+            char buf[8];
+
+            cur_pct = new_pct;
+            snprintf(buf, sizeof(buf), "%" PRId64, cur_pct);
+            property_set("vold.encrypt_progress", buf);
+        }
+        if (unix_read(realfd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) {
+            SLOGE("Error reading real_blkdev %s for inplace encrypt", crypto_blkdev);
+            goto errout;
+        }
+        if (unix_write(cryptofd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) {
+            SLOGE("Error writing crypto_blkdev %s for inplace encrypt", crypto_blkdev);
+            goto errout;
+        } else {
+            SLOGD("Encrypted %d block at %" PRId64,
+                  CRYPT_SECTORS_PER_BUFSIZE,
+                  i * CRYPT_SECTORS_PER_BUFSIZE);
+        }
+
+       if (!is_battery_ok_to_continue()) {
+            SLOGE("Stopping encryption due to low battery");
+            *size_already_done += (i + 1) * CRYPT_SECTORS_PER_BUFSIZE - 1;
+            rc = 0;
+            goto errout;
+        }
+    }
+
+    /* Do any remaining sectors */
+    for (i=0; i<remainder; i++) {
+        if (unix_read(realfd, buf, CRYPT_SECTOR_SIZE) <= 0) {
+            SLOGE("Error reading final sectors from real_blkdev %s for inplace encrypt", crypto_blkdev);
+            goto errout;
+        }
+        if (unix_write(cryptofd, buf, CRYPT_SECTOR_SIZE) <= 0) {
+            SLOGE("Error writing final sectors to crypto_blkdev %s for inplace encrypt", crypto_blkdev);
+            goto errout;
+        } else {
+            SLOGI("Encrypted 1 block at next location");
+        }
+    }
+
+    *size_already_done += size;
+    rc = 0;
+
+errout:
+    close(realfd);
+    close(cryptofd);
+
+    return rc;
+}
+
+/* returns on of the ENABLE_INPLACE_* return codes */
+int cryptfs_enable_inplace(char *crypto_blkdev, char *real_blkdev,
+                           off64_t size, off64_t *size_already_done,
+                           off64_t tot_size,
+                           off64_t previously_encrypted_upto)
+{
+    int rc_ext4, rc_f2fs, rc_full;
+    if (previously_encrypted_upto) {
+        SLOGD("Continuing encryption from %" PRId64, previously_encrypted_upto);
+    }
+
+    if (*size_already_done + size < previously_encrypted_upto) {
+        *size_already_done += size;
+        return 0;
+    }
+
+    /* 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, size_already_done,
+                                tot_size, previously_encrypted_upto)) == 0) {
+      return 0;
+    }
+    SLOGD("cryptfs_enable_inplace_ext4()=%d\n", rc_ext4);
+
+    if ((rc_f2fs = cryptfs_enable_inplace_f2fs(crypto_blkdev, real_blkdev,
+                                size, size_already_done,
+                                tot_size, previously_encrypted_upto)) == 0) {
+      return 0;
+    }
+    SLOGD("cryptfs_enable_inplace_f2fs()=%d\n", rc_f2fs);
+
+    rc_full = cryptfs_enable_inplace_full(crypto_blkdev, real_blkdev,
+                                       size, size_already_done, tot_size,
+                                       previously_encrypted_upto);
+    SLOGD("cryptfs_enable_inplace_full()=%d\n", rc_full);
+
+    /* Hack for b/17898962, the following is the symptom... */
+    if (rc_ext4 == ENABLE_INPLACE_ERR_DEV
+        && rc_f2fs == ENABLE_INPLACE_ERR_DEV
+        && rc_full == ENABLE_INPLACE_ERR_DEV) {
+            return ENABLE_INPLACE_ERR_DEV;
+    }
+    return rc_full;
+}