Messages in this thread | | | From | Michał Kępień <> | Subject | [PATCH v4 0/4] mtdchar: add MEMREAD ioctl | Date | Wed, 29 Jun 2022 14:57:33 +0200 |
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This patch series adds a new mtdchar ioctl, MEMREAD. Its purpose is to serve as a read counterpart of the MEMWRITE ioctl, exposing a broader set of capabilities for read operations (e.g. use of MTD_OPS_AUTO_OOB, access to ECC statistics) to user-space applications making use of MTD devices via /dev/mtd* character devices.
Changes from v3:
- Fixed two issues found by Richard Weinberger [1]:
- prevent integer overflow, - use kvmalloc() for potentially large allocations.
(Identical fixes have already been applied to mtdchar_write_ioctl(), i.e. the write counterpart of the ioctl proposed in this patch series, in mtd/next. [2] [3])
Changes from v2:
- Squashed patch 1/5 into patch 5/5 to prevent breaking bisectability due to an incompatible ABI change between those two patches. Revised commit messages accordingly.
Changes from v1:
- Added patches 2-5 which enable the new MEMREAD ioctl to report ECC statistics for the read operation back to user space. (There are obviously different ways these changes can be split up into separate commits; I was aiming for maximum ease of review.)
- The 'retlen' and 'oobretlen' fields were not set in the struct mtd_read_req returned to userspace. This was done properly in Boris' original draft patch [1], but I missed it in my v1.
- Invalid IS_ERR() checks were replaced with NULL checks. This was an artifact of copy-pasting mtdchar_write_ioctl() in v1: unlike memdup_user() used therein, kmalloc() always returns NULL on error.
- Minor subject prefix adjustment for patch 1/5 ("mtd" -> "mtdchar").
[1] http://lists.infradead.org/pipermail/linux-mtd/2022-February/091276.html [2] http://lists.infradead.org/pipermail/linux-mtd/2022-June/093829.html [3] http://lists.infradead.org/pipermail/linux-mtd/2022-June/093828.html
Michał Kępień (4): mtd: track maximum number of bitflips for each read request mtd: always initialize 'stats' in struct mtd_oob_ops mtd: add ECC error accounting for each read request mtdchar: add MEMREAD ioctl
drivers/mtd/devices/docg3.c | 8 ++ drivers/mtd/inftlcore.c | 6 +- drivers/mtd/mtdchar.c | 139 ++++++++++++++++++++++++ drivers/mtd/mtdcore.c | 5 + drivers/mtd/mtdswap.c | 6 +- drivers/mtd/nand/onenand/onenand_base.c | 16 ++- drivers/mtd/nand/onenand/onenand_bbt.c | 2 +- drivers/mtd/nand/raw/nand_base.c | 10 ++ drivers/mtd/nand/raw/nand_bbt.c | 8 +- drivers/mtd/nand/raw/sm_common.c | 2 +- drivers/mtd/nand/spi/core.c | 10 ++ drivers/mtd/nftlcore.c | 6 +- drivers/mtd/sm_ftl.c | 4 +- drivers/mtd/ssfdc.c | 2 +- drivers/mtd/tests/nandbiterrs.c | 2 +- drivers/mtd/tests/oobtest.c | 8 +- drivers/mtd/tests/readtest.c | 2 +- fs/jffs2/wbuf.c | 6 +- include/linux/mtd/mtd.h | 7 ++ include/uapi/mtd/mtd-abi.h | 64 ++++++++++- 20 files changed, 279 insertions(+), 34 deletions(-)
-- 2.37.0
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