Message ID | 20220629125737.14418-2-kernel@kempniu.pl |
---|---|
State | Accepted |
Delegated to: | Miquel Raynal |
Headers | show |
Series | mtdchar: add MEMREAD ioctl | expand |
On Wed, 2022-06-29 at 12:57:34 UTC, =?utf-8?b?TWljaGHFgiBLxJlwaWXFhA==?= wrote: > mtd_read_oob() callers are currently oblivious to the details of ECC > errors detected during the read operation - they only learn (through the > return value) whether any corrected bitflips or uncorrectable errors > occurred. More detailed ECC information can be useful to user-space > applications for making better-informed choices about moving data > around. > > Extend struct mtd_oob_ops with a pointer to a newly-introduced struct > mtd_req_stats and set its 'max_bitflips' field to the maximum number of > bitflips found in a single ECC step during the read operation performed > by mtd_read_oob(). This is a prerequisite for ultimately passing that > value back to user space. > > Suggested-by: Boris Brezillon <boris.brezillon@collabora.com> > Signed-off-by: Michał Kępień <kernel@kempniu.pl> Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/next, thanks. Miquel
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 6fafea80fd98..80c98e546d72 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -1622,6 +1622,9 @@ int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops) if (!master->_read_oob && (!master->_read || ops->oobbuf)) return -EOPNOTSUPP; + if (ops->stats) + memset(ops->stats, 0, sizeof(*ops->stats)); + if (mtd->flags & MTD_SLC_ON_MLC_EMULATION) ret_code = mtd_io_emulated_slc(mtd, from, true, ops); else @@ -1639,6 +1642,8 @@ int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops) return ret_code; if (mtd->ecc_strength == 0) return 0; /* device lacks ecc */ + if (ops->stats) + ops->stats->max_bitflips = ret_code; return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0; } EXPORT_SYMBOL_GPL(mtd_read_oob); diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 955aee14b0f7..fccad1766458 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -40,6 +40,10 @@ struct mtd_erase_region_info { unsigned long *lockmap; /* If keeping bitmap of locks */ }; +struct mtd_req_stats { + unsigned int max_bitflips; +}; + /** * struct mtd_oob_ops - oob operation operands * @mode: operation mode @@ -70,6 +74,7 @@ struct mtd_oob_ops { uint32_t ooboffs; uint8_t *datbuf; uint8_t *oobbuf; + struct mtd_req_stats *stats; }; /**
mtd_read_oob() callers are currently oblivious to the details of ECC errors detected during the read operation - they only learn (through the return value) whether any corrected bitflips or uncorrectable errors occurred. More detailed ECC information can be useful to user-space applications for making better-informed choices about moving data around. Extend struct mtd_oob_ops with a pointer to a newly-introduced struct mtd_req_stats and set its 'max_bitflips' field to the maximum number of bitflips found in a single ECC step during the read operation performed by mtd_read_oob(). This is a prerequisite for ultimately passing that value back to user space. Suggested-by: Boris Brezillon <boris.brezillon@collabora.com> Signed-off-by: Michał Kępień <kernel@kempniu.pl> --- drivers/mtd/mtdcore.c | 5 +++++ include/linux/mtd/mtd.h | 5 +++++ 2 files changed, 10 insertions(+)