diff mbox

[U-Boot,2/2] tools: env: Add support for direct read/write UBI volumes

Message ID 1462539510-18306-2-git-send-email-m.niestroj@grinn-global.com
State Changes Requested
Delegated to: Heiko Schocher
Headers show

Commit Message

Marcin Niestroj May 6, 2016, 12:58 p.m. UTC
Up to now we were able to read/write environment data from/to UBI
volumes only indirectly by gluebi driver. This driver creates NAND MTD
on top of UBI volumes, which is quite a workaroung for this use case.

Add support for direct read/write UBI volumes in order to not use
obsolete gluebi driver.

Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
---
 tools/env/fw_env.c      | 249 +++++++++++++++++++++++++++++++++++++++++++++++-
 tools/env/fw_env.config |   8 ++
 2 files changed, 256 insertions(+), 1 deletion(-)

Comments

Marcin Niestroj May 20, 2016, 1:37 p.m. UTC | #1
On 06.05.2016 14:58, Marcin Niestroj wrote:
> Up to now we were able to read/write environment data from/to UBI
> volumes only indirectly by gluebi driver. This driver creates NAND MTD
> on top of UBI volumes, which is quite a workaroung for this use case.
>
> Add support for direct read/write UBI volumes in order to not use
> obsolete gluebi driver.
>
> Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
> ---
>  tools/env/fw_env.c      | 249 +++++++++++++++++++++++++++++++++++++++++++++++-
>  tools/env/fw_env.config |   8 ++
>  2 files changed, 256 insertions(+), 1 deletion(-)
>
> diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
> index b4b542a..0e977e3 100644
> --- a/tools/env/fw_env.c
> +++ b/tools/env/fw_env.c
> @@ -24,6 +24,7 @@
>  #include <sys/ioctl.h>
>  #include <sys/stat.h>
>  #include <unistd.h>
> +#include <dirent.h>
>
>  #ifdef MTD_OLD
>  # include <stdint.h>
> @@ -33,6 +34,8 @@
>  # include <mtd/mtd-user.h>
>  #endif
>
> +#include <mtd/ubi-user.h>
> +
>  #include "fw_env.h"
>
>  struct common_args common_args;
> @@ -54,6 +57,7 @@ struct envdev_s {
>  	ulong erase_size;		/* device erase size */
>  	ulong env_sectors;		/* number of environment sectors */
>  	uint8_t mtd_type;		/* type of the MTD device */
> +	int is_ubi;			/* set if we use UBI volume */
>  };
>
>  static struct envdev_s envdevices[2] =
> @@ -72,6 +76,7 @@ static int dev_current;
>  #define DEVESIZE(i)   envdevices[(i)].erase_size
>  #define ENVSECTORS(i) envdevices[(i)].env_sectors
>  #define DEVTYPE(i)    envdevices[(i)].mtd_type
> +#define IS_UBI(i)     envdevices[(i)].is_ubi
>
>  #define CUR_ENVSIZE ENVSIZE(dev_current)
>
> @@ -117,6 +122,229 @@ static unsigned char obsolete_flag = 0;
>  #define DEFAULT_ENV_INSTANCE_STATIC
>  #include <env_default.h>
>
> +#define UBI_DEV_START "/dev/ubi"
> +#define UBI_SYSFS "/sys/class/ubi"
> +#define UBI_VOL_NAME_PATT "ubi%d_%d"
> +
> +static int is_ubi_devname(const char *devname)
> +{
> +	return !strncmp(devname, UBI_DEV_START, sizeof(UBI_DEV_START) - 1);
> +}
> +
> +static int ubi_check_volume_sysfs_name(const char *volume_sysfs_name,
> +				const char *volname)
> +{
> +	char path[256];
> +	FILE *file;
> +	char *name;
> +	int ret;
> +
> +	strcpy(path, UBI_SYSFS "/");
> +	strcat(path, volume_sysfs_name);
> +	strcat(path, "/name");
> +
> +	file = fopen(path, "r");
> +	if (!file)
> +		return -1;
> +
> +	ret = fscanf(file, "%ms", &name);
> +	fclose(file);
> +	if (ret <= 0 || !name) {
> +		fprintf(stderr,
> +			"Failed to read from file %s, ret = %d, name = %s\n",
> +			path, ret, name);
> +		return -1;
> +	}
> +
> +	if (!strcmp(name, volname)) {
> +		free(name);
> +		return 0;
> +	}
> +	free(name);
> +
> +	return -1;
> +}
> +
> +static int ubi_get_volnum_by_name(int devnum, const char *volname)
> +{
> +	DIR *sysfs_ubi;
> +	struct dirent *dirent;
> +	int ret;
> +	int tmp_devnum;
> +	int volnum;
> +
> +	sysfs_ubi = opendir(UBI_SYSFS);
> +	if (!sysfs_ubi)
> +		return -1;
> +
> +#ifdef DEBUG
> +	fprintf(stderr, "Looking for volume name \"%s\"\n", volname);
> +#endif
> +
> +	while (1) {
> +		dirent = readdir(sysfs_ubi);
> +		if (!dirent)
> +			return -1;
> +
> +		ret = sscanf(dirent->d_name, UBI_VOL_NAME_PATT,
> +				&tmp_devnum, &volnum);
> +		if (ret == 2 && devnum == tmp_devnum) {
> +			if (ubi_check_volume_sysfs_name(dirent->d_name,
> +								volname) == 0)
> +				return volnum;
> +		}
> +	}
> +
> +	return -1;
> +}
> +
> +static int ubi_get_devnum_by_devname(const char *devname)
> +{
> +	int devnum;
> +	int ret;
> +
> +	ret = sscanf(devname + sizeof(UBI_DEV_START) - 1, "%d", &devnum);
> +	if (ret != 1)
> +		return -1;
> +
> +	return devnum;
> +}
> +
> +static const char *ubi_get_volume_devname(const char *devname,
> +					const char *volname)
> +{
> +	char *volume_devname;
> +	int volnum;
> +	int devnum;
> +	int ret;
> +
> +	devnum = ubi_get_devnum_by_devname(devname);
> +	if (devnum < 0)
> +		return NULL;
> +
> +	volnum = ubi_get_volnum_by_name(devnum, volname);
> +	if (volnum < 0)
> +		return NULL;
> +
> +	ret = asprintf(&volume_devname, "%s_%d", devname, volnum);
> +	if (ret < 0)
> +		return NULL;
> +
> +#ifdef DEBUG
> +	fprintf(stderr, "Found ubi volume \"%s:%s\" -> %s\n",
> +		devname, volname, volume_devname);
> +#endif
> +
> +	return volume_devname;
> +}
> +
> +static void ubi_check_dev(unsigned int dev_id)
> +{
> +	char *devname = (char *) DEVNAME(dev_id);
> +	char *pname;
> +	const char *volname = NULL;
> +	const char *volume_devname;
> +
> +	if (!is_ubi_devname(DEVNAME(dev_id)))
> +		return;
> +
> +	IS_UBI(dev_id) = 1;
> +
> +	for (pname = devname; *pname != '\0'; pname++) {
> +		if (*pname == ':') {
> +			*pname = '\0';
> +			volname = pname + 1;
> +			break;
> +		}
> +	}
> +
> +	if (volname) {
> +		/* Let's find real volume device name */
> +		volume_devname = ubi_get_volume_devname(devname,
> +							volname);
> +		if (!volume_devname) {
> +			fprintf(stderr, "Didn't found ubi volume \"%s\"\n",
> +				volname);
> +			return;
> +		}
> +
> +		free(devname);
> +		DEVNAME(dev_id) = volume_devname;
> +	}
> +}
> +
> +static int ubi_update_start(int fd, int64_t bytes)
> +{
> +	if (ioctl(fd, UBI_IOCVOLUP, &bytes))
> +		return -1;
> +	return 0;
> +}
> +
> +static int ubi_read(int fd, void *buf, size_t count)
> +{
> +	ssize_t ret;
> +
> +	while (count > 0) {
> +		ret = read(fd, buf, count);
> +		if (ret > 0) {
> +			count -= ret;
> +			buf += ret;
> +
> +			continue;
> +		}
> +
> +		if (ret == 0) {
> +			/*
> +			 * Happens in case of too short volume data size. If we
> +			 * return error status we will fail it will be treated
> +			 * as UBI device error.
> +			 *
> +			 * Leave catching this error to CRC check.
> +			 */
> +			fprintf(stderr, "Warning: end of data on ubi volume\n");
> +			return 0;
> +		} else if (errno == EBADF) {
> +			/*
> +			 * Happens in case of corrupted volume. The same as
> +			 * above, we cannot return error now, as we will still
> +			 * be able to successfully write environment later.
> +			 */
> +			fprintf(stderr, "Warning: corrupted volume?\n");
> +			return 0;
> +		} else if (errno == EINTR) {
> +			continue;
> +		}
> +
> +		fprintf(stderr, "Cannot read %u bytes from ubi volume, %s\n",
> +			(unsigned int) count, strerror(errno));
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ubi_write(int fd, const void *buf, size_t count)
> +{
> +	ssize_t ret;
> +
> +	while (count > 0) {
> +		ret = write(fd, buf, count);
> +		if (ret <= 0) {
> +			if (ret < 0 && errno == EINTR)
> +				continue;
> +
> +			fprintf(stderr, "Cannot write %u bytes to ubi volume\n",
> +				(unsigned int) count);
> +			return -1;
> +		}
> +
> +		count -= ret;
> +		buf += ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static int flash_io (int mode);
>  static char *envmatch (char * s1, char * s2);
>  static int parse_config (void);
> @@ -997,6 +1225,12 @@ static int flash_write (int fd_current, int fd_target, int dev_target)
>  		DEVOFFSET (dev_target), DEVNAME (dev_target));
>  #endif
>
> +	if (IS_UBI(dev_target)) {
> +		if (ubi_update_start(fd_target, CUR_ENVSIZE) < 0)
> +			return 0;
> +		return ubi_write(fd_target, environment.image, CUR_ENVSIZE);
> +	}
> +
>  	rc = flash_write_buf(dev_target, fd_target, environment.image,
>  			      CUR_ENVSIZE, DEVOFFSET(dev_target),
>  			      DEVTYPE(dev_target));
> @@ -1024,6 +1258,12 @@ static int flash_read (int fd)
>  	struct stat st;
>  	int rc;
>
> +	if (IS_UBI(dev_current)) {
> +		DEVTYPE(dev_current) = MTD_ABSENT;
> +
> +		return ubi_read(fd, environment.image, CUR_ENVSIZE);
> +	}
> +
>  	rc = fstat(fd, &st);
>  	if (rc < 0) {
>  		fprintf(stderr, "Cannot stat the file %s\n",
> @@ -1236,7 +1476,8 @@ int fw_env_open(void)
>  			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
>  			environment.flag_scheme = FLAG_INCREMENTAL;
>  		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
> -			   DEVTYPE(!dev_current) == MTD_ABSENT) {
> +			   DEVTYPE(!dev_current) == MTD_ABSENT &&
> +			   IS_UBI(dev_current) == IS_UBI(!dev_current)) {
>  			environment.flag_scheme = FLAG_INCREMENTAL;
>  		} else {
>  			fprintf (stderr, "Incompatible flash types!\n");
> @@ -1369,6 +1610,12 @@ static int parse_config ()
>  	HaveRedundEnv = 1;
>  #endif
>  #endif
> +
> +	/* Fills in IS_UBI(), converts DEVNAME() with ubi volume name */
> +	ubi_check_dev(0);
> +	if (HaveRedundEnv)
> +		ubi_check_dev(1);
> +
>  	if (stat (DEVNAME (0), &st)) {
>  		fprintf (stderr,
>  			"Cannot access MTD device %s: %s\n",
> diff --git a/tools/env/fw_env.config b/tools/env/fw_env.config
> index 6f216f9..db5498a 100644
> --- a/tools/env/fw_env.config
> +++ b/tools/env/fw_env.config
> @@ -23,3 +23,11 @@
>
>  # VFAT example
>  #/boot/uboot.env	0x0000          0x4000
> +
> +# UBI volume
> +#/dev/ubi0_0		0x0		0x20000
> +#/dev/ubi0_1		0x0		0x20000
> +
> +# UBI volume by name
> +#/dev/ubi0:env		0x0		0x20000
> +#/dev/ubi0:env-redund	0x0		0x20000
>
Heiko Schocher July 26, 2016, 6:36 a.m. UTC | #2
Hello Marcin,

Sorry for the long delay

Am 06.05.2016 um 14:58 schrieb Marcin Niestroj:
> Up to now we were able to read/write environment data from/to UBI
> volumes only indirectly by gluebi driver. This driver creates NAND MTD
> on top of UBI volumes, which is quite a workaroung for this use case.
>
> Add support for direct read/write UBI volumes in order to not use
> obsolete gluebi driver.
>
> Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
> ---
>   tools/env/fw_env.c      | 249 +++++++++++++++++++++++++++++++++++++++++++++++-
>   tools/env/fw_env.config |   8 ++
>   2 files changed, 256 insertions(+), 1 deletion(-)

I tried to apply your patch, but this fails, and I was unsure,
if I could fix it correct... can you please send a new rebased
version?

Thanks!

bye,
Heiko
>
> diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
> index b4b542a..0e977e3 100644
> --- a/tools/env/fw_env.c
> +++ b/tools/env/fw_env.c
> @@ -24,6 +24,7 @@
>   #include <sys/ioctl.h>
>   #include <sys/stat.h>
>   #include <unistd.h>
> +#include <dirent.h>
>
>   #ifdef MTD_OLD
>   # include <stdint.h>
> @@ -33,6 +34,8 @@
>   # include <mtd/mtd-user.h>
>   #endif
>
> +#include <mtd/ubi-user.h>
> +
>   #include "fw_env.h"
>
>   struct common_args common_args;
> @@ -54,6 +57,7 @@ struct envdev_s {
>   	ulong erase_size;		/* device erase size */
>   	ulong env_sectors;		/* number of environment sectors */
>   	uint8_t mtd_type;		/* type of the MTD device */
> +	int is_ubi;			/* set if we use UBI volume */
>   };
>
>   static struct envdev_s envdevices[2] =
> @@ -72,6 +76,7 @@ static int dev_current;
>   #define DEVESIZE(i)   envdevices[(i)].erase_size
>   #define ENVSECTORS(i) envdevices[(i)].env_sectors
>   #define DEVTYPE(i)    envdevices[(i)].mtd_type
> +#define IS_UBI(i)     envdevices[(i)].is_ubi
>
>   #define CUR_ENVSIZE ENVSIZE(dev_current)
>
> @@ -117,6 +122,229 @@ static unsigned char obsolete_flag = 0;
>   #define DEFAULT_ENV_INSTANCE_STATIC
>   #include <env_default.h>
>
> +#define UBI_DEV_START "/dev/ubi"
> +#define UBI_SYSFS "/sys/class/ubi"
> +#define UBI_VOL_NAME_PATT "ubi%d_%d"
> +
> +static int is_ubi_devname(const char *devname)
> +{
> +	return !strncmp(devname, UBI_DEV_START, sizeof(UBI_DEV_START) - 1);
> +}
> +
> +static int ubi_check_volume_sysfs_name(const char *volume_sysfs_name,
> +				const char *volname)
> +{
> +	char path[256];
> +	FILE *file;
> +	char *name;
> +	int ret;
> +
> +	strcpy(path, UBI_SYSFS "/");
> +	strcat(path, volume_sysfs_name);
> +	strcat(path, "/name");
> +
> +	file = fopen(path, "r");
> +	if (!file)
> +		return -1;
> +
> +	ret = fscanf(file, "%ms", &name);
> +	fclose(file);
> +	if (ret <= 0 || !name) {
> +		fprintf(stderr,
> +			"Failed to read from file %s, ret = %d, name = %s\n",
> +			path, ret, name);
> +		return -1;
> +	}
> +
> +	if (!strcmp(name, volname)) {
> +		free(name);
> +		return 0;
> +	}
> +	free(name);
> +
> +	return -1;
> +}
> +
> +static int ubi_get_volnum_by_name(int devnum, const char *volname)
> +{
> +	DIR *sysfs_ubi;
> +	struct dirent *dirent;
> +	int ret;
> +	int tmp_devnum;
> +	int volnum;
> +
> +	sysfs_ubi = opendir(UBI_SYSFS);
> +	if (!sysfs_ubi)
> +		return -1;
> +
> +#ifdef DEBUG
> +	fprintf(stderr, "Looking for volume name \"%s\"\n", volname);
> +#endif
> +
> +	while (1) {
> +		dirent = readdir(sysfs_ubi);
> +		if (!dirent)
> +			return -1;
> +
> +		ret = sscanf(dirent->d_name, UBI_VOL_NAME_PATT,
> +				&tmp_devnum, &volnum);
> +		if (ret == 2 && devnum == tmp_devnum) {
> +			if (ubi_check_volume_sysfs_name(dirent->d_name,
> +								volname) == 0)
> +				return volnum;
> +		}
> +	}
> +
> +	return -1;
> +}
> +
> +static int ubi_get_devnum_by_devname(const char *devname)
> +{
> +	int devnum;
> +	int ret;
> +
> +	ret = sscanf(devname + sizeof(UBI_DEV_START) - 1, "%d", &devnum);
> +	if (ret != 1)
> +		return -1;
> +
> +	return devnum;
> +}
> +
> +static const char *ubi_get_volume_devname(const char *devname,
> +					const char *volname)
> +{
> +	char *volume_devname;
> +	int volnum;
> +	int devnum;
> +	int ret;
> +
> +	devnum = ubi_get_devnum_by_devname(devname);
> +	if (devnum < 0)
> +		return NULL;
> +
> +	volnum = ubi_get_volnum_by_name(devnum, volname);
> +	if (volnum < 0)
> +		return NULL;
> +
> +	ret = asprintf(&volume_devname, "%s_%d", devname, volnum);
> +	if (ret < 0)
> +		return NULL;
> +
> +#ifdef DEBUG
> +	fprintf(stderr, "Found ubi volume \"%s:%s\" -> %s\n",
> +		devname, volname, volume_devname);
> +#endif
> +
> +	return volume_devname;
> +}
> +
> +static void ubi_check_dev(unsigned int dev_id)
> +{
> +	char *devname = (char *) DEVNAME(dev_id);
> +	char *pname;
> +	const char *volname = NULL;
> +	const char *volume_devname;
> +
> +	if (!is_ubi_devname(DEVNAME(dev_id)))
> +		return;
> +
> +	IS_UBI(dev_id) = 1;
> +
> +	for (pname = devname; *pname != '\0'; pname++) {
> +		if (*pname == ':') {
> +			*pname = '\0';
> +			volname = pname + 1;
> +			break;
> +		}
> +	}
> +
> +	if (volname) {
> +		/* Let's find real volume device name */
> +		volume_devname = ubi_get_volume_devname(devname,
> +							volname);
> +		if (!volume_devname) {
> +			fprintf(stderr, "Didn't found ubi volume \"%s\"\n",
> +				volname);
> +			return;
> +		}
> +
> +		free(devname);
> +		DEVNAME(dev_id) = volume_devname;
> +	}
> +}
> +
> +static int ubi_update_start(int fd, int64_t bytes)
> +{
> +	if (ioctl(fd, UBI_IOCVOLUP, &bytes))
> +		return -1;
> +	return 0;
> +}
> +
> +static int ubi_read(int fd, void *buf, size_t count)
> +{
> +	ssize_t ret;
> +
> +	while (count > 0) {
> +		ret = read(fd, buf, count);
> +		if (ret > 0) {
> +			count -= ret;
> +			buf += ret;
> +
> +			continue;
> +		}
> +
> +		if (ret == 0) {
> +			/*
> +			 * Happens in case of too short volume data size. If we
> +			 * return error status we will fail it will be treated
> +			 * as UBI device error.
> +			 *
> +			 * Leave catching this error to CRC check.
> +			 */
> +			fprintf(stderr, "Warning: end of data on ubi volume\n");
> +			return 0;
> +		} else if (errno == EBADF) {
> +			/*
> +			 * Happens in case of corrupted volume. The same as
> +			 * above, we cannot return error now, as we will still
> +			 * be able to successfully write environment later.
> +			 */
> +			fprintf(stderr, "Warning: corrupted volume?\n");
> +			return 0;
> +		} else if (errno == EINTR) {
> +			continue;
> +		}
> +
> +		fprintf(stderr, "Cannot read %u bytes from ubi volume, %s\n",
> +			(unsigned int) count, strerror(errno));
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ubi_write(int fd, const void *buf, size_t count)
> +{
> +	ssize_t ret;
> +
> +	while (count > 0) {
> +		ret = write(fd, buf, count);
> +		if (ret <= 0) {
> +			if (ret < 0 && errno == EINTR)
> +				continue;
> +
> +			fprintf(stderr, "Cannot write %u bytes to ubi volume\n",
> +				(unsigned int) count);
> +			return -1;
> +		}
> +
> +		count -= ret;
> +		buf += ret;
> +	}
> +
> +	return 0;
> +}
> +
>   static int flash_io (int mode);
>   static char *envmatch (char * s1, char * s2);
>   static int parse_config (void);
> @@ -997,6 +1225,12 @@ static int flash_write (int fd_current, int fd_target, int dev_target)
>   		DEVOFFSET (dev_target), DEVNAME (dev_target));
>   #endif
>
> +	if (IS_UBI(dev_target)) {
> +		if (ubi_update_start(fd_target, CUR_ENVSIZE) < 0)
> +			return 0;
> +		return ubi_write(fd_target, environment.image, CUR_ENVSIZE);
> +	}
> +
>   	rc = flash_write_buf(dev_target, fd_target, environment.image,
>   			      CUR_ENVSIZE, DEVOFFSET(dev_target),
>   			      DEVTYPE(dev_target));
> @@ -1024,6 +1258,12 @@ static int flash_read (int fd)
>   	struct stat st;
>   	int rc;
>
> +	if (IS_UBI(dev_current)) {
> +		DEVTYPE(dev_current) = MTD_ABSENT;
> +
> +		return ubi_read(fd, environment.image, CUR_ENVSIZE);
> +	}
> +
>   	rc = fstat(fd, &st);
>   	if (rc < 0) {
>   		fprintf(stderr, "Cannot stat the file %s\n",
> @@ -1236,7 +1476,8 @@ int fw_env_open(void)
>   			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
>   			environment.flag_scheme = FLAG_INCREMENTAL;
>   		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
> -			   DEVTYPE(!dev_current) == MTD_ABSENT) {
> +			   DEVTYPE(!dev_current) == MTD_ABSENT &&
> +			   IS_UBI(dev_current) == IS_UBI(!dev_current)) {
>   			environment.flag_scheme = FLAG_INCREMENTAL;
>   		} else {
>   			fprintf (stderr, "Incompatible flash types!\n");
> @@ -1369,6 +1610,12 @@ static int parse_config ()
>   	HaveRedundEnv = 1;
>   #endif
>   #endif
> +
> +	/* Fills in IS_UBI(), converts DEVNAME() with ubi volume name */
> +	ubi_check_dev(0);
> +	if (HaveRedundEnv)
> +		ubi_check_dev(1);
> +
>   	if (stat (DEVNAME (0), &st)) {
>   		fprintf (stderr,
>   			"Cannot access MTD device %s: %s\n",
> diff --git a/tools/env/fw_env.config b/tools/env/fw_env.config
> index 6f216f9..db5498a 100644
> --- a/tools/env/fw_env.config
> +++ b/tools/env/fw_env.config
> @@ -23,3 +23,11 @@
>
>   # VFAT example
>   #/boot/uboot.env	0x0000          0x4000
> +
> +# UBI volume
> +#/dev/ubi0_0		0x0		0x20000
> +#/dev/ubi0_1		0x0		0x20000
> +
> +# UBI volume by name
> +#/dev/ubi0:env		0x0		0x20000
> +#/dev/ubi0:env-redund	0x0		0x20000
>
diff mbox

Patch

diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
index b4b542a..0e977e3 100644
--- a/tools/env/fw_env.c
+++ b/tools/env/fw_env.c
@@ -24,6 +24,7 @@ 
 #include <sys/ioctl.h>
 #include <sys/stat.h>
 #include <unistd.h>
+#include <dirent.h>
 
 #ifdef MTD_OLD
 # include <stdint.h>
@@ -33,6 +34,8 @@ 
 # include <mtd/mtd-user.h>
 #endif
 
+#include <mtd/ubi-user.h>
+
 #include "fw_env.h"
 
 struct common_args common_args;
@@ -54,6 +57,7 @@  struct envdev_s {
 	ulong erase_size;		/* device erase size */
 	ulong env_sectors;		/* number of environment sectors */
 	uint8_t mtd_type;		/* type of the MTD device */
+	int is_ubi;			/* set if we use UBI volume */
 };
 
 static struct envdev_s envdevices[2] =
@@ -72,6 +76,7 @@  static int dev_current;
 #define DEVESIZE(i)   envdevices[(i)].erase_size
 #define ENVSECTORS(i) envdevices[(i)].env_sectors
 #define DEVTYPE(i)    envdevices[(i)].mtd_type
+#define IS_UBI(i)     envdevices[(i)].is_ubi
 
 #define CUR_ENVSIZE ENVSIZE(dev_current)
 
@@ -117,6 +122,229 @@  static unsigned char obsolete_flag = 0;
 #define DEFAULT_ENV_INSTANCE_STATIC
 #include <env_default.h>
 
+#define UBI_DEV_START "/dev/ubi"
+#define UBI_SYSFS "/sys/class/ubi"
+#define UBI_VOL_NAME_PATT "ubi%d_%d"
+
+static int is_ubi_devname(const char *devname)
+{
+	return !strncmp(devname, UBI_DEV_START, sizeof(UBI_DEV_START) - 1);
+}
+
+static int ubi_check_volume_sysfs_name(const char *volume_sysfs_name,
+				const char *volname)
+{
+	char path[256];
+	FILE *file;
+	char *name;
+	int ret;
+
+	strcpy(path, UBI_SYSFS "/");
+	strcat(path, volume_sysfs_name);
+	strcat(path, "/name");
+
+	file = fopen(path, "r");
+	if (!file)
+		return -1;
+
+	ret = fscanf(file, "%ms", &name);
+	fclose(file);
+	if (ret <= 0 || !name) {
+		fprintf(stderr,
+			"Failed to read from file %s, ret = %d, name = %s\n",
+			path, ret, name);
+		return -1;
+	}
+
+	if (!strcmp(name, volname)) {
+		free(name);
+		return 0;
+	}
+	free(name);
+
+	return -1;
+}
+
+static int ubi_get_volnum_by_name(int devnum, const char *volname)
+{
+	DIR *sysfs_ubi;
+	struct dirent *dirent;
+	int ret;
+	int tmp_devnum;
+	int volnum;
+
+	sysfs_ubi = opendir(UBI_SYSFS);
+	if (!sysfs_ubi)
+		return -1;
+
+#ifdef DEBUG
+	fprintf(stderr, "Looking for volume name \"%s\"\n", volname);
+#endif
+
+	while (1) {
+		dirent = readdir(sysfs_ubi);
+		if (!dirent)
+			return -1;
+
+		ret = sscanf(dirent->d_name, UBI_VOL_NAME_PATT,
+				&tmp_devnum, &volnum);
+		if (ret == 2 && devnum == tmp_devnum) {
+			if (ubi_check_volume_sysfs_name(dirent->d_name,
+								volname) == 0)
+				return volnum;
+		}
+	}
+
+	return -1;
+}
+
+static int ubi_get_devnum_by_devname(const char *devname)
+{
+	int devnum;
+	int ret;
+
+	ret = sscanf(devname + sizeof(UBI_DEV_START) - 1, "%d", &devnum);
+	if (ret != 1)
+		return -1;
+
+	return devnum;
+}
+
+static const char *ubi_get_volume_devname(const char *devname,
+					const char *volname)
+{
+	char *volume_devname;
+	int volnum;
+	int devnum;
+	int ret;
+
+	devnum = ubi_get_devnum_by_devname(devname);
+	if (devnum < 0)
+		return NULL;
+
+	volnum = ubi_get_volnum_by_name(devnum, volname);
+	if (volnum < 0)
+		return NULL;
+
+	ret = asprintf(&volume_devname, "%s_%d", devname, volnum);
+	if (ret < 0)
+		return NULL;
+
+#ifdef DEBUG
+	fprintf(stderr, "Found ubi volume \"%s:%s\" -> %s\n",
+		devname, volname, volume_devname);
+#endif
+
+	return volume_devname;
+}
+
+static void ubi_check_dev(unsigned int dev_id)
+{
+	char *devname = (char *) DEVNAME(dev_id);
+	char *pname;
+	const char *volname = NULL;
+	const char *volume_devname;
+
+	if (!is_ubi_devname(DEVNAME(dev_id)))
+		return;
+
+	IS_UBI(dev_id) = 1;
+
+	for (pname = devname; *pname != '\0'; pname++) {
+		if (*pname == ':') {
+			*pname = '\0';
+			volname = pname + 1;
+			break;
+		}
+	}
+
+	if (volname) {
+		/* Let's find real volume device name */
+		volume_devname = ubi_get_volume_devname(devname,
+							volname);
+		if (!volume_devname) {
+			fprintf(stderr, "Didn't found ubi volume \"%s\"\n",
+				volname);
+			return;
+		}
+
+		free(devname);
+		DEVNAME(dev_id) = volume_devname;
+	}
+}
+
+static int ubi_update_start(int fd, int64_t bytes)
+{
+	if (ioctl(fd, UBI_IOCVOLUP, &bytes))
+		return -1;
+	return 0;
+}
+
+static int ubi_read(int fd, void *buf, size_t count)
+{
+	ssize_t ret;
+
+	while (count > 0) {
+		ret = read(fd, buf, count);
+		if (ret > 0) {
+			count -= ret;
+			buf += ret;
+
+			continue;
+		}
+
+		if (ret == 0) {
+			/*
+			 * Happens in case of too short volume data size. If we
+			 * return error status we will fail it will be treated
+			 * as UBI device error.
+			 *
+			 * Leave catching this error to CRC check.
+			 */
+			fprintf(stderr, "Warning: end of data on ubi volume\n");
+			return 0;
+		} else if (errno == EBADF) {
+			/*
+			 * Happens in case of corrupted volume. The same as
+			 * above, we cannot return error now, as we will still
+			 * be able to successfully write environment later.
+			 */
+			fprintf(stderr, "Warning: corrupted volume?\n");
+			return 0;
+		} else if (errno == EINTR) {
+			continue;
+		}
+
+		fprintf(stderr, "Cannot read %u bytes from ubi volume, %s\n",
+			(unsigned int) count, strerror(errno));
+		return -1;
+	}
+
+	return 0;
+}
+
+static int ubi_write(int fd, const void *buf, size_t count)
+{
+	ssize_t ret;
+
+	while (count > 0) {
+		ret = write(fd, buf, count);
+		if (ret <= 0) {
+			if (ret < 0 && errno == EINTR)
+				continue;
+
+			fprintf(stderr, "Cannot write %u bytes to ubi volume\n",
+				(unsigned int) count);
+			return -1;
+		}
+
+		count -= ret;
+		buf += ret;
+	}
+
+	return 0;
+}
+
 static int flash_io (int mode);
 static char *envmatch (char * s1, char * s2);
 static int parse_config (void);
@@ -997,6 +1225,12 @@  static int flash_write (int fd_current, int fd_target, int dev_target)
 		DEVOFFSET (dev_target), DEVNAME (dev_target));
 #endif
 
+	if (IS_UBI(dev_target)) {
+		if (ubi_update_start(fd_target, CUR_ENVSIZE) < 0)
+			return 0;
+		return ubi_write(fd_target, environment.image, CUR_ENVSIZE);
+	}
+
 	rc = flash_write_buf(dev_target, fd_target, environment.image,
 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
 			      DEVTYPE(dev_target));
@@ -1024,6 +1258,12 @@  static int flash_read (int fd)
 	struct stat st;
 	int rc;
 
+	if (IS_UBI(dev_current)) {
+		DEVTYPE(dev_current) = MTD_ABSENT;
+
+		return ubi_read(fd, environment.image, CUR_ENVSIZE);
+	}
+
 	rc = fstat(fd, &st);
 	if (rc < 0) {
 		fprintf(stderr, "Cannot stat the file %s\n",
@@ -1236,7 +1476,8 @@  int fw_env_open(void)
 			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
 			environment.flag_scheme = FLAG_INCREMENTAL;
 		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
-			   DEVTYPE(!dev_current) == MTD_ABSENT) {
+			   DEVTYPE(!dev_current) == MTD_ABSENT &&
+			   IS_UBI(dev_current) == IS_UBI(!dev_current)) {
 			environment.flag_scheme = FLAG_INCREMENTAL;
 		} else {
 			fprintf (stderr, "Incompatible flash types!\n");
@@ -1369,6 +1610,12 @@  static int parse_config ()
 	HaveRedundEnv = 1;
 #endif
 #endif
+
+	/* Fills in IS_UBI(), converts DEVNAME() with ubi volume name */
+	ubi_check_dev(0);
+	if (HaveRedundEnv)
+		ubi_check_dev(1);
+
 	if (stat (DEVNAME (0), &st)) {
 		fprintf (stderr,
 			"Cannot access MTD device %s: %s\n",
diff --git a/tools/env/fw_env.config b/tools/env/fw_env.config
index 6f216f9..db5498a 100644
--- a/tools/env/fw_env.config
+++ b/tools/env/fw_env.config
@@ -23,3 +23,11 @@ 
 
 # VFAT example
 #/boot/uboot.env	0x0000          0x4000
+
+# UBI volume
+#/dev/ubi0_0		0x0		0x20000
+#/dev/ubi0_1		0x0		0x20000
+
+# UBI volume by name
+#/dev/ubi0:env		0x0		0x20000
+#/dev/ubi0:env-redund	0x0		0x20000