From 0c6c7fa1313fcb69cae35e34168d2e83b8da854a Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Fri, 26 Jun 2009 14:58:01 +0300 Subject: UBI: add image sequence number to EC header An image sequence number is added to the UBI erase-counter header to be able determine if the root file system contains a mixture of old and new images (because the flashing failed to complete). A change to nolo is also needed for this to take effect. Signed-off-by: Adrian Hunter Signed-off-by: Artem Bityutskiy --- drivers/mtd/ubi/build.c | 1 + drivers/mtd/ubi/debug.c | 2 ++ drivers/mtd/ubi/io.c | 15 +++++++++++++-- drivers/mtd/ubi/scan.c | 2 ++ drivers/mtd/ubi/ubi-media.h | 12 +++++++++++- drivers/mtd/ubi/ubi.h | 4 ++++ 6 files changed, 33 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 286ed594e5a..db0b9cb64c6 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -996,6 +996,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset) ubi_msg("number of PEBs reserved for bad PEB handling: %d", ubi->beb_rsvd_pebs); ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec); + ubi_msg("image sequence number: %d", ubi->image_seq); /* * The below lock makes sure we do not race with 'ubi_thread()' which diff --git a/drivers/mtd/ubi/debug.c b/drivers/mtd/ubi/debug.c index c0ed60e8ade..54b0186915f 100644 --- a/drivers/mtd/ubi/debug.c +++ b/drivers/mtd/ubi/debug.c @@ -44,6 +44,8 @@ void ubi_dbg_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr) be32_to_cpu(ec_hdr->vid_hdr_offset)); printk(KERN_DEBUG "\tdata_offset %d\n", be32_to_cpu(ec_hdr->data_offset)); + printk(KERN_DEBUG "\timage_seq %d\n", + be32_to_cpu(ec_hdr->image_seq)); printk(KERN_DEBUG "\thdr_crc %#08x\n", be32_to_cpu(ec_hdr->hdr_crc)); printk(KERN_DEBUG "erase counter header hexdump:\n"); diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c index c8edbfd09b6..b5871401109 100644 --- a/drivers/mtd/ubi/io.c +++ b/drivers/mtd/ubi/io.c @@ -563,15 +563,16 @@ int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum) * This function returns zero if the erase counter header is OK, and %1 if * not. */ -static int validate_ec_hdr(const struct ubi_device *ubi, +static int validate_ec_hdr(struct ubi_device *ubi, const struct ubi_ec_hdr *ec_hdr) { long long ec; - int vid_hdr_offset, leb_start; + int vid_hdr_offset, leb_start, image_seq; ec = be64_to_cpu(ec_hdr->ec); vid_hdr_offset = be32_to_cpu(ec_hdr->vid_hdr_offset); leb_start = be32_to_cpu(ec_hdr->data_offset); + image_seq = be32_to_cpu(ec_hdr->image_seq); if (ec_hdr->version != UBI_VERSION) { ubi_err("node with incompatible UBI version found: " @@ -597,6 +598,15 @@ static int validate_ec_hdr(const struct ubi_device *ubi, goto bad; } + if (!ubi->image_seq_set) { + ubi->image_seq = image_seq; + ubi->image_seq_set = 1; + } else if (ubi->image_seq != image_seq) { + ubi_err("bad image sequence number %d, expected %d", + image_seq, ubi->image_seq); + goto bad; + } + return 0; bad: @@ -742,6 +752,7 @@ int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum, ec_hdr->version = UBI_VERSION; ec_hdr->vid_hdr_offset = cpu_to_be32(ubi->vid_hdr_offset); ec_hdr->data_offset = cpu_to_be32(ubi->leb_start); + ec_hdr->image_seq = cpu_to_be32(ubi->image_seq); crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); ec_hdr->hdr_crc = cpu_to_be32(crc); diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c index c3d653ba5ca..72570ed7d33 100644 --- a/drivers/mtd/ubi/scan.c +++ b/drivers/mtd/ubi/scan.c @@ -910,6 +910,8 @@ struct ubi_scan_info *ubi_scan(struct ubi_device *ubi) if (si->is_empty) ubi_msg("empty MTD device detected"); + ubi->image_seq_set = 1; + /* * In case of unknown erase counter we use the mean erase counter * value. diff --git a/drivers/mtd/ubi/ubi-media.h b/drivers/mtd/ubi/ubi-media.h index 8419fdccc79..503ea9b2730 100644 --- a/drivers/mtd/ubi/ubi-media.h +++ b/drivers/mtd/ubi/ubi-media.h @@ -129,6 +129,7 @@ enum { * @ec: the erase counter * @vid_hdr_offset: where the VID header starts * @data_offset: where the user data start + * @image_seq: image sequence number * @padding2: reserved for future, zeroes * @hdr_crc: erase counter header CRC checksum * @@ -144,6 +145,14 @@ enum { * volume identifier header and user data, relative to the beginning of the * physical eraseblock. These values have to be the same for all physical * eraseblocks. + * + * The @image_seq field is used to validate a UBI image that has been prepared + * for a UBI device. The @image_seq value can be any value, but it must be the + * same on all eraseblocks. UBI will ensure that all new erase counter headers + * also contain this value, and will check the value when scanning at start-up. + * One way to make use of @image_seq is to increase its value by one every time + * an image is flashed over an existing image, then, if the flashing does not + * complete, UBI will detect the error when scanning. */ struct ubi_ec_hdr { __be32 magic; @@ -152,7 +161,8 @@ struct ubi_ec_hdr { __be64 ec; /* Warning: the current limit is 31-bit anyway! */ __be32 vid_hdr_offset; __be32 data_offset; - __u8 padding2[36]; + __be32 image_seq; + __u8 padding2[32]; __be32 hdr_crc; } __attribute__ ((packed)); diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index 28acd133c99..bb372c4222b 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -301,6 +301,8 @@ struct ubi_wl_entry; * @vol->readers, @vol->writers, @vol->exclusive, * @vol->ref_count, @vol->mapping and @vol->eba_tbl. * @ref_count: count of references on the UBI device + * @image_seq: image sequence number recorded on EC headers + * @image_seq_set: indicates @image_seq is known * * @rsvd_pebs: count of reserved physical eraseblocks * @avail_pebs: count of available physical eraseblocks @@ -390,6 +392,8 @@ struct ubi_device { struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT]; spinlock_t volumes_lock; int ref_count; + int image_seq; + int image_seq_set; int rsvd_pebs; int avail_pebs; -- cgit v1.2.3-70-g09d2