diff options
| -rw-r--r-- | drivers/mtd/ubi/eba.c | 55 | ||||
| -rw-r--r-- | drivers/mtd/ubi/kapi.c | 95 | ||||
| -rw-r--r-- | drivers/mtd/ubi/ubi.h | 3 | ||||
| -rw-r--r-- | include/linux/mtd/ubi.h | 48 |
4 files changed, 186 insertions, 15 deletions
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c index a40020cf0923..f1db73da7975 100644 --- a/drivers/mtd/ubi/eba.c +++ b/drivers/mtd/ubi/eba.c @@ -480,6 +480,61 @@ out_unlock: } /** + * ubi_eba_read_leb_sg - read data into a scatter gather list. + * @ubi: UBI device description object + * @vol: volume description object + * @lnum: logical eraseblock number + * @sgl: UBI scatter gather list to store the read data + * @offset: offset from where to read + * @len: how many bytes to read + * @check: data CRC check flag + * + * This function works exactly like ubi_eba_read_leb(). But instead of + * storing the read data into a buffer it writes to an UBI scatter gather + * list. + */ +int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol, + struct ubi_sgl *sgl, int lnum, int offset, int len, + int check) +{ + int to_read; + int ret; + struct scatterlist *sg; + + for (;;) { + ubi_assert(sgl->list_pos < UBI_MAX_SG_COUNT); + sg = &sgl->sg[sgl->list_pos]; + if (len < sg->length - sgl->page_pos) + to_read = len; + else + to_read = sg->length - sgl->page_pos; + + ret = ubi_eba_read_leb(ubi, vol, lnum, + sg_virt(sg) + sgl->page_pos, offset, + to_read, check); + if (ret < 0) + return ret; + + offset += to_read; + len -= to_read; + if (!len) { + sgl->page_pos += to_read; + if (sgl->page_pos == sg->length) { + sgl->list_pos++; + sgl->page_pos = 0; + } + + break; + } + + sgl->list_pos++; + sgl->page_pos = 0; + } + + return ret; +} + +/** * recover_peb - recover from write failure. * @ubi: UBI device description object * @pnum: the physical eraseblock to recover diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c index 589c423fac2d..478e00cf2d9e 100644 --- a/drivers/mtd/ubi/kapi.c +++ b/drivers/mtd/ubi/kapi.c @@ -366,6 +366,43 @@ void ubi_close_volume(struct ubi_volume_desc *desc) EXPORT_SYMBOL_GPL(ubi_close_volume); /** + * leb_read_sanity_check - does sanity checks on read requests. + * @desc: volume descriptor + * @lnum: logical eraseblock number to read from + * @offset: offset within the logical eraseblock to read from + * @len: how many bytes to read + * + * This function is used by ubi_leb_read() and ubi_leb_read_sg() + * to perform sanity checks. + */ +static int leb_read_sanity_check(struct ubi_volume_desc *desc, int lnum, + int offset, int len) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int vol_id = vol->vol_id; + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 || + lnum >= vol->used_ebs || offset < 0 || len < 0 || + offset + len > vol->usable_leb_size) + return -EINVAL; + + if (vol->vol_type == UBI_STATIC_VOLUME) { + if (vol->used_ebs == 0) + /* Empty static UBI volume */ + return 0; + if (lnum == vol->used_ebs - 1 && + offset + len > vol->last_eb_bytes) + return -EINVAL; + } + + if (vol->upd_marker) + return -EBADF; + + return 0; +} + +/** * ubi_leb_read - read data. * @desc: volume descriptor * @lnum: logical eraseblock number to read from @@ -401,22 +438,10 @@ int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, dbg_gen("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset); - if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 || - lnum >= vol->used_ebs || offset < 0 || len < 0 || - offset + len > vol->usable_leb_size) - return -EINVAL; - - if (vol->vol_type == UBI_STATIC_VOLUME) { - if (vol->used_ebs == 0) - /* Empty static UBI volume */ - return 0; - if (lnum == vol->used_ebs - 1 && - offset + len > vol->last_eb_bytes) - return -EINVAL; - } + err = leb_read_sanity_check(desc, lnum, offset, len); + if (err < 0) + return err; - if (vol->upd_marker) - return -EBADF; if (len == 0) return 0; @@ -430,6 +455,46 @@ int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, } EXPORT_SYMBOL_GPL(ubi_leb_read); + +/** + * ubi_leb_read_sg - read data into a scatter gather list. + * @desc: volume descriptor + * @lnum: logical eraseblock number to read from + * @buf: buffer where to store the read data + * @offset: offset within the logical eraseblock to read from + * @len: how many bytes to read + * @check: whether UBI has to check the read data's CRC or not. + * + * This function works exactly like ubi_leb_read_sg(). But instead of + * storing the read data into a buffer it writes to an UBI scatter gather + * list. + */ +int ubi_leb_read_sg(struct ubi_volume_desc *desc, int lnum, struct ubi_sgl *sgl, + int offset, int len, int check) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int err, vol_id = vol->vol_id; + + dbg_gen("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset); + + err = leb_read_sanity_check(desc, lnum, offset, len); + if (err < 0) + return err; + + if (len == 0) + return 0; + + err = ubi_eba_read_leb_sg(ubi, vol, sgl, lnum, offset, len, check); + if (err && mtd_is_eccerr(err) && vol->vol_type == UBI_STATIC_VOLUME) { + ubi_warn(ubi, "mark volume %d as corrupted", vol_id); + vol->corrupted = 1; + } + + return err; +} +EXPORT_SYMBOL_GPL(ubi_leb_read_sg); + /** * ubi_leb_write - write data. * @desc: volume descriptor diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index 20cabc060b61..d94b81fa2306 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -795,6 +795,9 @@ int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum); int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, void *buf, int offset, int len, int check); +int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol, + struct ubi_sgl *sgl, int lnum, int offset, int len, + int check); int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, const void *buf, int offset, int len); int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol, diff --git a/include/linux/mtd/ubi.h b/include/linux/mtd/ubi.h index 8fa2753316e8..1e271cb559cd 100644 --- a/include/linux/mtd/ubi.h +++ b/include/linux/mtd/ubi.h @@ -23,12 +23,19 @@ #include <linux/ioctl.h> #include <linux/types.h> +#include <linux/scatterlist.h> #include <mtd/ubi-user.h> /* All voumes/LEBs */ #define UBI_ALL -1 /* + * Maximum number of scatter gather list entries, + * we use only 64 to have a lower memory foot print. + */ +#define UBI_MAX_SG_COUNT 64 + +/* * enum ubi_open_mode - UBI volume open mode constants. * * UBI_READONLY: read-only mode @@ -119,6 +126,35 @@ struct ubi_volume_info { }; /** + * struct ubi_sgl - UBI scatter gather list data structure. + * @list_pos: current position in @sg[] + * @page_pos: current position in @sg[@list_pos] + * @sg: the scatter gather list itself + * + * ubi_sgl is a wrapper around a scatter list which keeps track of the + * current position in the list and the current list item such that + * it can be used across multiple ubi_leb_read_sg() calls. + */ +struct ubi_sgl { + int list_pos; + int page_pos; + struct scatterlist sg[UBI_MAX_SG_COUNT]; +}; + +/** + * ubi_sgl_init - initialize an UBI scatter gather list data structure. + * @usgl: the UBI scatter gather struct itself + * + * Please note that you still have to use sg_init_table() or any adequate + * function to initialize the unterlaying struct scatterlist. + */ +static inline void ubi_sgl_init(struct ubi_sgl *usgl) +{ + usgl->list_pos = 0; + usgl->page_pos = 0; +} + +/** * struct ubi_device_info - UBI device description data structure. * @ubi_num: ubi device number * @leb_size: logical eraseblock size on this UBI device @@ -213,6 +249,8 @@ int ubi_unregister_volume_notifier(struct notifier_block *nb); void ubi_close_volume(struct ubi_volume_desc *desc); int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, int len, int check); +int ubi_leb_read_sg(struct ubi_volume_desc *desc, int lnum, struct ubi_sgl *sgl, + int offset, int len, int check); int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, int offset, int len); int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, @@ -233,4 +271,14 @@ static inline int ubi_read(struct ubi_volume_desc *desc, int lnum, char *buf, { return ubi_leb_read(desc, lnum, buf, offset, len, 0); } + +/* + * This function is the same as the 'ubi_leb_read_sg()' function, but it does + * not provide the checking capability. + */ +static inline int ubi_read_sg(struct ubi_volume_desc *desc, int lnum, + struct ubi_sgl *sgl, int offset, int len) +{ + return ubi_leb_read_sg(desc, lnum, sgl, offset, len, 0); +} #endif /* !__LINUX_UBI_H__ */ |