From e511c4a3d2a1f64aafc1f5df37a2ffcf7ef91b55 Mon Sep 17 00:00:00 2001 From: Jane Chu Date: Fri, 13 May 2022 15:10:58 -0700 Subject: dax: introduce DAX_RECOVERY_WRITE dax access mode Up till now, dax_direct_access() is used implicitly for normal access, but for the purpose of recovery write, dax range with poison is requested. To make the interface clear, introduce enum dax_access_mode { DAX_ACCESS, DAX_RECOVERY_WRITE, } where DAX_ACCESS is used for normal dax access, and DAX_RECOVERY_WRITE is used for dax recovery write. Suggested-by: Dan Williams Signed-off-by: Jane Chu Reviewed-by: Christoph Hellwig Cc: Mike Snitzer Reviewed-by: Vivek Goyal Link: https://lore.kernel.org/r/165247982851.52965.11024212198889762949.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams --- include/linux/device-mapper.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include/linux/device-mapper.h') diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index c2a3758c4aaa..acdedda0d12b 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -20,6 +20,7 @@ struct dm_table; struct dm_report_zones_args; struct mapped_device; struct bio_vec; +enum dax_access_mode; /* * Type of table, mapped_device's mempool and request_queue @@ -146,7 +147,8 @@ typedef int (*dm_busy_fn) (struct dm_target *ti); * >= 0 : the number of bytes accessible at the address */ typedef long (*dm_dax_direct_access_fn) (struct dm_target *ti, pgoff_t pgoff, - long nr_pages, void **kaddr, pfn_t *pfn); + long nr_pages, enum dax_access_mode node, void **kaddr, + pfn_t *pfn); typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff, size_t nr_pages); -- cgit v1.2.3 From 047218ec904da19c45c4a70274fc3f818a1fcba1 Mon Sep 17 00:00:00 2001 From: Jane Chu Date: Fri, 22 Apr 2022 16:45:06 -0600 Subject: dax: add .recovery_write dax_operation Introduce dax_recovery_write() operation. The function is used to recover a dax range that contains poison. Typical use case is when a user process receives a SIGBUS with si_code BUS_MCEERR_AR indicating poison(s) in a dax range, in response, the user process issues a pwrite() to the page-aligned dax range, thus clears the poison and puts valid data in the range. Reviewed-by: Christoph Hellwig Signed-off-by: Jane Chu Link: https://lore.kernel.org/r/20220422224508.440670-6-jane.chu@oracle.com Signed-off-by: Dan Williams --- include/linux/device-mapper.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/linux/device-mapper.h') diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index acdedda0d12b..47a01c7cffdf 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -152,6 +152,14 @@ typedef long (*dm_dax_direct_access_fn) (struct dm_target *ti, pgoff_t pgoff, typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff, size_t nr_pages); +/* + * Returns: + * != 0 : number of bytes transferred + * 0 : recovery write failed + */ +typedef size_t (*dm_dax_recovery_write_fn)(struct dm_target *ti, pgoff_t pgoff, + void *addr, size_t bytes, struct iov_iter *i); + void dm_error(const char *message); struct dm_dev { @@ -201,6 +209,7 @@ struct target_type { dm_io_hints_fn io_hints; dm_dax_direct_access_fn direct_access; dm_dax_zero_page_range_fn dax_zero_page_range; + dm_dax_recovery_write_fn dax_recovery_write; /* For internal device-mapper use. */ struct list_head list; -- cgit v1.2.3