diff options
Diffstat (limited to 'mtdutils')
| -rw-r--r-- | mtdutils/Android.mk | 21 | ||||
| -rw-r--r-- | mtdutils/flash_image.c | 140 | ||||
| -rw-r--r-- | mtdutils/mounts.c | 214 | ||||
| -rw-r--r-- | mtdutils/mounts.h | 31 | ||||
| -rw-r--r-- | mtdutils/mtdutils.c | 510 | ||||
| -rw-r--r-- | mtdutils/mtdutils.h | 54 |
6 files changed, 970 insertions, 0 deletions
diff --git a/mtdutils/Android.mk b/mtdutils/Android.mk new file mode 100644 index 000000000..c75eb0133 --- /dev/null +++ b/mtdutils/Android.mk @@ -0,0 +1,21 @@ +ifneq ($(TARGET_SIMULATOR),true) + +LOCAL_PATH := $(call my-dir) +include $(CLEAR_VARS) + +LOCAL_SRC_FILES := \ + mtdutils.c \ + mounts.c + +LOCAL_MODULE := libmtdutils + +include $(BUILD_STATIC_LIBRARY) + +include $(CLEAR_VARS) +LOCAL_SRC_FILES := flash_image.c +LOCAL_MODULE := flash_image +LOCAL_STATIC_LIBRARIES := libmtdutils +LOCAL_SHARED_LIBRARIES := libcutils libc +include $(BUILD_EXECUTABLE) + +endif # !TARGET_SIMULATOR diff --git a/mtdutils/flash_image.c b/mtdutils/flash_image.c new file mode 100644 index 000000000..c77687602 --- /dev/null +++ b/mtdutils/flash_image.c @@ -0,0 +1,140 @@ +/* + * Copyright (C) 2008 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 <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "cutils/log.h" +#include "mtdutils.h" + +#define LOG_TAG "flash_image" + +#define HEADER_SIZE 2048 // size of header to compare for equality + +void die(const char *msg, ...) { + int err = errno; + va_list args; + va_start(args, msg); + char buf[1024]; + vsnprintf(buf, sizeof(buf), msg, args); + va_end(args); + + if (err != 0) { + strlcat(buf, ": ", sizeof(buf)); + strlcat(buf, strerror(err), sizeof(buf)); + } + + fprintf(stderr, "%s\n", buf); + LOGE("%s\n", buf); + exit(1); +} + +/* Read an image file and write it to a flash partition. */ + +int main(int argc, char **argv) { + const MtdPartition *ptn; + MtdWriteContext *write; + void *data; + unsigned sz; + + if (argc != 3) { + fprintf(stderr, "usage: %s partition file.img\n", argv[0]); + return 2; + } + + if (mtd_scan_partitions() <= 0) die("error scanning partitions"); + const MtdPartition *partition = mtd_find_partition_by_name(argv[1]); + if (partition == NULL) die("can't find %s partition", argv[1]); + + // If the first part of the file matches the partition, skip writing + + int fd = open(argv[2], O_RDONLY); + if (fd < 0) die("error opening %s", argv[2]); + + char header[HEADER_SIZE]; + int headerlen = read(fd, header, sizeof(header)); + if (headerlen <= 0) die("error reading %s header", argv[2]); + + MtdReadContext *in = mtd_read_partition(partition); + if (in == NULL) { + LOGW("error opening %s: %s\n", argv[1], strerror(errno)); + // just assume it needs re-writing + } else { + char check[HEADER_SIZE]; + int checklen = mtd_read_data(in, check, sizeof(check)); + if (checklen <= 0) { + LOGW("error reading %s: %s\n", argv[1], strerror(errno)); + // just assume it needs re-writing + } else if (checklen == headerlen && !memcmp(header, check, headerlen)) { + LOGI("header is the same, not flashing %s\n", argv[1]); + return 0; + } + mtd_read_close(in); + } + + // Skip the header (we'll come back to it), write everything else + LOGI("flashing %s from %s\n", argv[1], argv[2]); + + MtdWriteContext *out = mtd_write_partition(partition); + if (out == NULL) die("error writing %s", argv[1]); + + char buf[HEADER_SIZE]; + memset(buf, 0, headerlen); + int wrote = mtd_write_data(out, buf, headerlen); + if (wrote != headerlen) die("error writing %s", argv[1]); + + int len; + while ((len = read(fd, buf, sizeof(buf))) > 0) { + wrote = mtd_write_data(out, buf, len); + if (wrote != len) die("error writing %s", argv[1]); + } + if (len < 0) die("error reading %s", argv[2]); + + if (mtd_write_close(out)) die("error closing %s", argv[1]); + + // Now come back and write the header last + + out = mtd_write_partition(partition); + if (out == NULL) die("error re-opening %s", argv[1]); + + wrote = mtd_write_data(out, header, headerlen); + if (wrote != headerlen) die("error re-writing %s", argv[1]); + + // Need to write a complete block, so write the rest of the first block + size_t block_size; + if (mtd_partition_info(partition, NULL, &block_size, NULL)) + die("error getting %s block size", argv[1]); + + if (lseek(fd, headerlen, SEEK_SET) != headerlen) + die("error rewinding %s", argv[2]); + + int left = block_size - headerlen; + while (left < 0) left += block_size; + while (left > 0) { + len = read(fd, buf, left > (int)sizeof(buf) ? (int)sizeof(buf) : left); + if (len <= 0) die("error reading %s", argv[2]); + if (mtd_write_data(out, buf, len) != len) + die("error writing %s", argv[1]); + left -= len; + } + + if (mtd_write_close(out)) die("error closing %s", argv[1]); + return 0; +} diff --git a/mtdutils/mounts.c b/mtdutils/mounts.c new file mode 100644 index 000000000..2ab3ff60c --- /dev/null +++ b/mtdutils/mounts.c @@ -0,0 +1,214 @@ +/* + * Copyright (C) 2007 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 <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <fcntl.h> +#include <errno.h> +#include <sys/mount.h> + +#include "mounts.h" + +struct MountedVolume { + const char *device; + const char *mount_point; + const char *filesystem; + const char *flags; +}; + +typedef struct { + MountedVolume *volumes; + int volumes_allocd; + int volume_count; +} MountsState; + +static MountsState g_mounts_state = { + NULL, // volumes + 0, // volumes_allocd + 0 // volume_count +}; + +static inline void +free_volume_internals(const MountedVolume *volume, int zero) +{ + free((char *)volume->device); + free((char *)volume->mount_point); + free((char *)volume->filesystem); + free((char *)volume->flags); + if (zero) { + memset((void *)volume, 0, sizeof(*volume)); + } +} + +#define PROC_MOUNTS_FILENAME "/proc/mounts" + +int +scan_mounted_volumes() +{ + char buf[2048]; + const char *bufp; + int fd; + ssize_t nbytes; + + if (g_mounts_state.volumes == NULL) { + const int numv = 32; + MountedVolume *volumes = malloc(numv * sizeof(*volumes)); + if (volumes == NULL) { + errno = ENOMEM; + return -1; + } + g_mounts_state.volumes = volumes; + g_mounts_state.volumes_allocd = numv; + memset(volumes, 0, numv * sizeof(*volumes)); + } else { + /* Free the old volume strings. + */ + int i; + for (i = 0; i < g_mounts_state.volume_count; i++) { + free_volume_internals(&g_mounts_state.volumes[i], 1); + } + } + g_mounts_state.volume_count = 0; + + /* Open and read the file contents. + */ + fd = open(PROC_MOUNTS_FILENAME, O_RDONLY); + if (fd < 0) { + goto bail; + } + nbytes = read(fd, buf, sizeof(buf) - 1); + close(fd); + if (nbytes < 0) { + goto bail; + } + buf[nbytes] = '\0'; + + /* Parse the contents of the file, which looks like: + * + * # cat /proc/mounts + * rootfs / rootfs rw 0 0 + * /dev/pts /dev/pts devpts rw 0 0 + * /proc /proc proc rw 0 0 + * /sys /sys sysfs rw 0 0 + * /dev/block/mtdblock4 /system yaffs2 rw,nodev,noatime,nodiratime 0 0 + * /dev/block/mtdblock5 /data yaffs2 rw,nodev,noatime,nodiratime 0 0 + * /dev/block/mmcblk0p1 /sdcard vfat rw,sync,dirsync,fmask=0000,dmask=0000,codepage=cp437,iocharset=iso8859-1,utf8 0 0 + * + * The zeroes at the end are dummy placeholder fields to make the + * output match Linux's /etc/mtab, but don't represent anything here. + */ + bufp = buf; + while (nbytes > 0) { + char device[64]; + char mount_point[64]; + char filesystem[64]; + char flags[128]; + int matches; + + /* %as is a gnu extension that malloc()s a string for each field. + */ + matches = sscanf(bufp, "%63s %63s %63s %127s", + device, mount_point, filesystem, flags); + + if (matches == 4) { + device[sizeof(device)-1] = '\0'; + mount_point[sizeof(mount_point)-1] = '\0'; + filesystem[sizeof(filesystem)-1] = '\0'; + flags[sizeof(flags)-1] = '\0'; + + MountedVolume *v = + &g_mounts_state.volumes[g_mounts_state.volume_count++]; + v->device = strdup(device); + v->mount_point = strdup(mount_point); + v->filesystem = strdup(filesystem); + v->flags = strdup(flags); + } else { +printf("matches was %d on <<%.40s>>\n", matches, bufp); + } + + /* Eat the line. + */ + while (nbytes > 0 && *bufp != '\n') { + bufp++; + nbytes--; + } + if (nbytes > 0) { + bufp++; + nbytes--; + } + } + + return 0; + +bail: +//TODO: free the strings we've allocated. + g_mounts_state.volume_count = 0; + return -1; +} + +const MountedVolume * +find_mounted_volume_by_device(const char *device) +{ + if (g_mounts_state.volumes != NULL) { + int i; + for (i = 0; i < g_mounts_state.volume_count; i++) { + MountedVolume *v = &g_mounts_state.volumes[i]; + /* May be null if it was unmounted and we haven't rescanned. + */ + if (v->device != NULL) { + if (strcmp(v->device, device) == 0) { + return v; + } + } + } + } + return NULL; +} + +const MountedVolume * +find_mounted_volume_by_mount_point(const char *mount_point) +{ + if (g_mounts_state.volumes != NULL) { + int i; + for (i = 0; i < g_mounts_state.volume_count; i++) { + MountedVolume *v = &g_mounts_state.volumes[i]; + /* May be null if it was unmounted and we haven't rescanned. + */ + if (v->mount_point != NULL) { + if (strcmp(v->mount_point, mount_point) == 0) { + return v; + } + } + } + } + return NULL; +} + +int +unmount_mounted_volume(const MountedVolume *volume) +{ + /* Intentionally pass NULL to umount if the caller tries + * to unmount a volume they already unmounted using this + * function. + */ + int ret = umount(volume->mount_point); + if (ret == 0) { + free_volume_internals(volume, 1); + return 0; + } + return ret; +} diff --git a/mtdutils/mounts.h b/mtdutils/mounts.h new file mode 100644 index 000000000..2e2765a93 --- /dev/null +++ b/mtdutils/mounts.h @@ -0,0 +1,31 @@ +/* + * Copyright (C) 2007 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. + */ + +#ifndef MTDUTILS_MOUNTS_H_ +#define MTDUTILS_MOUNTS_H_ + +typedef struct MountedVolume MountedVolume; + +int scan_mounted_volumes(void); + +const MountedVolume *find_mounted_volume_by_device(const char *device); + +const MountedVolume * +find_mounted_volume_by_mount_point(const char *mount_point); + +int unmount_mounted_volume(const MountedVolume *volume); + +#endif // MTDUTILS_MOUNTS_H_ diff --git a/mtdutils/mtdutils.c b/mtdutils/mtdutils.c new file mode 100644 index 000000000..2b0106f14 --- /dev/null +++ b/mtdutils/mtdutils.c @@ -0,0 +1,510 @@ +/* + * Copyright (C) 2007 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 <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <errno.h> +#include <sys/mount.h> // for _IOW, _IOR, mount() +#include <sys/stat.h> +#include <mtd/mtd-user.h> +#undef NDEBUG +#include <assert.h> + +#include "mtdutils.h" + +struct MtdPartition { + int device_index; + unsigned int size; + unsigned int erase_size; + char *name; +}; + +struct MtdReadContext { + const MtdPartition *partition; + char *buffer; + size_t consumed; + int fd; +}; + +struct MtdWriteContext { + const MtdPartition *partition; + char *buffer; + size_t stored; + int fd; +}; + +typedef struct { + MtdPartition *partitions; + int partitions_allocd; + int partition_count; +} MtdState; + +static MtdState g_mtd_state = { + NULL, // partitions + 0, // partitions_allocd + -1 // partition_count +}; + +#define MTD_PROC_FILENAME "/proc/mtd" + +int +mtd_scan_partitions() +{ + char buf[2048]; + const char *bufp; + int fd; + int i; + ssize_t nbytes; + + if (g_mtd_state.partitions == NULL) { + const int nump = 32; + MtdPartition *partitions = malloc(nump * sizeof(*partitions)); + if (partitions == NULL) { + errno = ENOMEM; + return -1; + } + g_mtd_state.partitions = partitions; + g_mtd_state.partitions_allocd = nump; + memset(partitions, 0, nump * sizeof(*partitions)); + } + g_mtd_state.partition_count = 0; + + /* Initialize all of the entries to make things easier later. + * (Lets us handle sparsely-numbered partitions, which + * may not even be possible.) + */ + for (i = 0; i < g_mtd_state.partitions_allocd; i++) { + MtdPartition *p = &g_mtd_state.partitions[i]; + if (p->name != NULL) { + free(p->name); + p->name = NULL; + } + p->device_index = -1; + } + + /* Open and read the file contents. + */ + fd = open(MTD_PROC_FILENAME, O_RDONLY); + if (fd < 0) { + goto bail; + } + nbytes = read(fd, buf, sizeof(buf) - 1); + close(fd); + if (nbytes < 0) { + goto bail; + } + buf[nbytes] = '\0'; + + /* Parse the contents of the file, which looks like: + * + * # cat /proc/mtd + * dev: size erasesize name + * mtd0: 00080000 00020000 "bootloader" + * mtd1: 00400000 00020000 "mfg_and_gsm" + * mtd2: 00400000 00020000 "0000000c" + * mtd3: 00200000 00020000 "0000000d" + * mtd4: 04000000 00020000 "system" + * mtd5: 03280000 00020000 "userdata" + */ + bufp = buf; + while (nbytes > 0) { + int mtdnum, mtdsize, mtderasesize; + int matches; + char mtdname[64]; + mtdname[0] = '\0'; + mtdnum = -1; + + matches = sscanf(bufp, "mtd%d: %x %x \"%63[^\"]", + &mtdnum, &mtdsize, &mtderasesize, mtdname); + /* This will fail on the first line, which just contains + * column headers. + */ + if (matches == 4) { + MtdPartition *p = &g_mtd_state.partitions[mtdnum]; + p->device_index = mtdnum; + p->size = mtdsize; + p->erase_size = mtderasesize; + p->name = strdup(mtdname); + if (p->name == NULL) { + errno = ENOMEM; + goto bail; + } + g_mtd_state.partition_count++; + } + + /* Eat the line. + */ + while (nbytes > 0 && *bufp != '\n') { + bufp++; + nbytes--; + } + if (nbytes > 0) { + bufp++; + nbytes--; + } + } + + return g_mtd_state.partition_count; + +bail: + // keep "partitions" around so we can free the names on a rescan. + g_mtd_state.partition_count = -1; + return -1; +} + +const MtdPartition * +mtd_find_partition_by_name(const char *name) +{ + if (g_mtd_state.partitions != NULL) { + int i; + for (i = 0; i < g_mtd_state.partitions_allocd; i++) { + MtdPartition *p = &g_mtd_state.partitions[i]; + if (p->device_index >= 0 && p->name != NULL) { + if (strcmp(p->name, name) == 0) { + return p; + } + } + } + } + return NULL; +} + +int +mtd_mount_partition(const MtdPartition *partition, const char *mount_point, + const char *filesystem, int read_only) +{ + const unsigned long flags = MS_NOATIME | MS_NODEV | MS_NODIRATIME; + char devname[64]; + int rv = -1; + + sprintf(devname, "/dev/block/mtdblock%d", partition->device_index); + if (!read_only) { + rv = mount(devname, mount_point, filesystem, flags, NULL); + } + if (read_only || rv < 0) { + rv = mount(devname, mount_point, filesystem, flags | MS_RDONLY, 0); + if (rv < 0) { + printf("Failed to mount %s on %s: %s\n", + devname, mount_point, strerror(errno)); + } else { + printf("Mount %s on %s read-only\n", devname, mount_point); + } + } +#if 1 //TODO: figure out why this is happening; remove include of stat.h + if (rv >= 0) { + /* For some reason, the x bits sometimes aren't set on the root + * of mounted volumes. + */ + struct stat st; + rv = stat(mount_point, &st); + if (rv < 0) { + return rv; + } + mode_t new_mode = st.st_mode | S_IXUSR | S_IXGRP | S_IXOTH; + if (new_mode != st.st_mode) { +printf("Fixing execute permissions for %s\n", mount_point); + rv = chmod(mount_point, new_mode); + if (rv < 0) { + printf("Couldn't fix permissions for %s: %s\n", + mount_point, strerror(errno)); + } + } + } +#endif + return rv; +} + +int +mtd_partition_info(const MtdPartition *partition, + size_t *total_size, size_t *erase_size, size_t *write_size) +{ + char mtddevname[32]; + sprintf(mtddevname, "/dev/mtd/mtd%d", partition->device_index); + int fd = open(mtddevname, O_RDONLY); + if (fd < 0) return -1; + + struct mtd_info_user mtd_info; + int ret = ioctl(fd, MEMGETINFO, &mtd_info); + close(fd); + if (ret < 0) return -1; + + if (total_size != NULL) *total_size = mtd_info.size; + if (erase_size != NULL) *erase_size = mtd_info.erasesize; + if (write_size != NULL) *write_size = mtd_info.writesize; + return 0; +} + +MtdReadContext *mtd_read_partition(const MtdPartition *partition) +{ + MtdReadContext *ctx = (MtdReadContext*) malloc(sizeof(MtdReadContext)); + if (ctx == NULL) return NULL; + + ctx->buffer = malloc(partition->erase_size); + if (ctx->buffer == NULL) { + free(ctx); + return NULL; + } + + char mtddevname[32]; + sprintf(mtddevname, "/dev/mtd/mtd%d", partition->device_index); + ctx->fd = open(mtddevname, O_RDONLY); + if (ctx->fd < 0) { + free(ctx); + free(ctx->buffer); + return NULL; + } + + ctx->partition = partition; + ctx->consumed = partition->erase_size; + return ctx; +} + +static int read_block(const MtdPartition *partition, int fd, char *data) +{ + struct mtd_ecc_stats before, after; + if (ioctl(fd, ECCGETSTATS, &before)) { + fprintf(stderr, "mtd: ECCGETSTATS error (%s)\n", strerror(errno)); + return -1; + } + + off_t pos = lseek(fd, 0, SEEK_CUR); + ssize_t size = partition->erase_size; + while (pos + size <= (int) partition->size) { + if (lseek(fd, pos, SEEK_SET) != pos || read(fd, data, size) != size) { + fprintf(stderr, "mtd: read error at 0x%08lx (%s)\n", + pos, strerror(errno)); + } else if (ioctl(fd, ECCGETSTATS, &after)) { + fprintf(stderr, "mtd: ECCGETSTATS error (%s)\n", strerror(errno)); + return -1; + } else if (after.failed != before.failed) { + fprintf(stderr, "mtd: ECC errors (%d soft, %d hard) at 0x%08lx\n", + after.corrected - before.corrected, + after.failed - before.failed, pos); + } else { + return 0; // Success! + } + + pos += partition->erase_size; + } + + errno = ENOSPC; + return -1; +} + +ssize_t mtd_read_data(MtdReadContext *ctx, char *data, size_t len) +{ + ssize_t read = 0; + while (read < (int) len) { + if (ctx->consumed < ctx->partition->erase_size) { + size_t avail = ctx->partition->erase_size - ctx->consumed; + size_t copy = len - read < avail ? len - read : avail; + memcpy(data + read, ctx->buffer + ctx->consumed, copy); + ctx->consumed += copy; + read += copy; + } + + // Read complete blocks directly into the user's buffer + while (ctx->consumed == ctx->partition->erase_size && + len - read >= ctx->partition->erase_size) { + if (read_block(ctx->partition, ctx->fd, data + read)) return -1; + read += ctx->partition->erase_size; + } + + // Read the next block into the buffer + if (ctx->consumed == ctx->partition->erase_size && read < (int) len) { + if (read_block(ctx->partition, ctx->fd, ctx->buffer)) return -1; + ctx->consumed = 0; + } + } + + return read; +} + +void mtd_read_close(MtdReadContext *ctx) +{ + close(ctx->fd); + free(ctx->buffer); + free(ctx); +} + +MtdWriteContext *mtd_write_partition(const MtdPartition *partition) +{ + MtdWriteContext *ctx = (MtdWriteContext*) malloc(sizeof(MtdWriteContext)); + if (ctx == NULL) return NULL; + + ctx->buffer = malloc(partition->erase_size); + if (ctx->buffer == NULL) { + free(ctx); + return NULL; + } + + char mtddevname[32]; + sprintf(mtddevname, "/dev/mtd/mtd%d", partition->device_index); + ctx->fd = open(mtddevname, O_RDWR); + if (ctx->fd < 0) { + free(ctx->buffer); + free(ctx); + return NULL; + } + + ctx->partition = partition; + ctx->stored = 0; + return ctx; +} + +static int write_block(const MtdPartition *partition, int fd, const char *data) +{ + off_t pos = lseek(fd, 0, SEEK_CUR); + if (pos == (off_t) -1) return 1; + + ssize_t size = partition->erase_size; + while (pos + size <= (int) partition->size) { + loff_t bpos = pos; + if (ioctl(fd, MEMGETBADBLOCK, &bpos) > 0) { + fprintf(stderr, "mtd: not writing bad block at 0x%08lx\n", pos); + pos += partition->erase_size; + continue; // Don't try to erase known factory-bad blocks. + } + + struct erase_info_user erase_info; + erase_info.start = pos; + erase_info.length = size; + int retry; + for (retry = 0; retry < 2; ++retry) { + if (ioctl(fd, MEMERASE, &erase_info) < 0) { + fprintf(stderr, "mtd: erase failure at 0x%08lx (%s)\n", + pos, strerror(errno)); + continue; + } + if (lseek(fd, pos, SEEK_SET) != pos || + write(fd, data, size) != size) { + fprintf(stderr, "mtd: write error at 0x%08lx (%s)\n", + pos, strerror(errno)); + } + + char verify[size]; + if (lseek(fd, pos, SEEK_SET) != pos || + read(fd, verify, size) != size) { + fprintf(stderr, "mtd: re-read error at 0x%08lx (%s)\n", + pos, strerror(errno)); + continue; + } + if (memcmp(data, verify, size) != 0) { + fprintf(stderr, "mtd: verification error at 0x%08lx (%s)\n", + pos, strerror(errno)); + continue; + } + + if (retry > 0) { + fprintf(stderr, "mtd: wrote block after %d retries\n", retry); + } + return 0; // Success! + } + + // Try to erase it once more as we give up on this block + fprintf(stderr, "mtd: skipping write block at 0x%08lx\n", pos); + ioctl(fd, MEMERASE, &erase_info); + pos += partition->erase_size; + } + + // Ran out of space on the device + errno = ENOSPC; + return -1; +} + +ssize_t mtd_write_data(MtdWriteContext *ctx, const char *data, size_t len) +{ + size_t wrote = 0; + while (wrote < len) { + // Coalesce partial writes into complete blocks + if (ctx->stored > 0 || len - wrote < ctx->partition->erase_size) { + size_t avail = ctx->partition->erase_size - ctx->stored; + size_t copy = len - wrote < avail ? len - wrote : avail; + memcpy(ctx->buffer + ctx->stored, data + wrote, copy); + ctx->stored += copy; + wrote += copy; + } + + // If a complete block was accumulated, write it + if (ctx->stored == ctx->partition->erase_size) { + if (write_block(ctx->partition, ctx->fd, ctx->buffer)) return -1; + ctx->stored = 0; + } + + // Write complete blocks directly from the user's buffer + while (ctx->stored == 0 && len - wrote >= ctx->partition->erase_size) { + if (write_block(ctx->partition, ctx->fd, data + wrote)) return -1; + wrote += ctx->partition->erase_size; + } + } + + return wrote; +} + +off_t mtd_erase_blocks(MtdWriteContext *ctx, int blocks) +{ + // Zero-pad and write any pending data to get us to a block boundary + if (ctx->stored > 0) { + size_t zero = ctx->partition->erase_size - ctx->stored; + memset(ctx->buffer + ctx->stored, 0, zero); + if (write_block(ctx->partition, ctx->fd, ctx->buffer)) return -1; + ctx->stored = 0; + } + + off_t pos = lseek(ctx->fd, 0, SEEK_CUR); + if ((off_t) pos == (off_t) -1) return pos; + + const int total = (ctx->partition->size - pos) / ctx->partition->erase_size; + if (blocks < 0) blocks = total; + if (blocks > total) { + errno = ENOSPC; + return -1; + } + + // Erase the specified number of blocks + while (blocks-- > 0) { + loff_t bpos = pos; + if (ioctl(ctx->fd, MEMGETBADBLOCK, &bpos) > 0) { + fprintf(stderr, "mtd: not erasing bad block at 0x%08lx\n", pos); + pos += ctx->partition->erase_size; + continue; // Don't try to erase known factory-bad blocks. + } + + struct erase_info_user erase_info; + erase_info.start = pos; + erase_info.length = ctx->partition->erase_size; + if (ioctl(ctx->fd, MEMERASE, &erase_info) < 0) { + fprintf(stderr, "mtd: erase failure at 0x%08lx\n", pos); + } + pos += ctx->partition->erase_size; + } + + return pos; +} + +int mtd_write_close(MtdWriteContext *ctx) +{ + int r = 0; + // Make sure any pending data gets written + if (mtd_erase_blocks(ctx, 0) == (off_t) -1) r = -1; + if (close(ctx->fd)) r = -1; + free(ctx->buffer); + free(ctx); + return r; +} diff --git a/mtdutils/mtdutils.h b/mtdutils/mtdutils.h new file mode 100644 index 000000000..8d2cb56b1 --- /dev/null +++ b/mtdutils/mtdutils.h @@ -0,0 +1,54 @@ +/* + * Copyright (C) 2007 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. + */ + +#ifndef MTDUTILS_H_ +#define MTDUTILS_H_ + +#include <sys/types.h> // for size_t, etc. + +typedef struct MtdPartition MtdPartition; + +int mtd_scan_partitions(void); + +const MtdPartition *mtd_find_partition_by_name(const char *name); + +/* mount_point is like "/system" + * filesystem is like "yaffs2" + */ +int mtd_mount_partition(const MtdPartition *partition, const char *mount_point, + const char *filesystem, int read_only); + +/* get the partition and the minimum erase/write block size. NULL is ok. + */ +int mtd_partition_info(const MtdPartition *partition, + size_t *total_size, size_t *erase_size, size_t *write_size); + +/* read or write raw data from a partition, starting at the beginning. + * skips bad blocks as best we can. + */ +typedef struct MtdReadContext MtdReadContext; +typedef struct MtdWriteContext MtdWriteContext; + +MtdReadContext *mtd_read_partition(const MtdPartition *); +ssize_t mtd_read_data(MtdReadContext *, char *data, size_t data_len); +void mtd_read_close(MtdReadContext *); + +MtdWriteContext *mtd_write_partition(const MtdPartition *); +ssize_t mtd_write_data(MtdWriteContext *, const char *data, size_t data_len); +off_t mtd_erase_blocks(MtdWriteContext *, int blocks); /* 0 ok, -1 for all */ +int mtd_write_close(MtdWriteContext *); + +#endif // MTDUTILS_H_ |