diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/mtd/ubi.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/include/linux/mtd/ubi.h b/include/linux/mtd/ubi.h index 8fa2753316e..1e271cb559c 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__ */ |