2022-05-14 03:55:23

by Dan Williams

[permalink] [raw]
Subject: [PATCH v11 4/7] dax: introduce DAX_RECOVERY_WRITE dax access mode

From: Jane Chu <[email protected]>

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 <[email protected]>
Signed-off-by: Jane Chu <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Mike Snitzer <[email protected]>
Signed-off-by: Dan Williams <[email protected]>
---
Changes since v10:
- fixup compile error in tools/testing/nvdimm/pmem-dax.c

drivers/dax/super.c | 5 +++--
drivers/md/dm-linear.c | 5 +++--
drivers/md/dm-log-writes.c | 5 +++--
drivers/md/dm-stripe.c | 5 +++--
drivers/md/dm-target.c | 4 +++-
drivers/md/dm-writecache.c | 7 ++++---
drivers/md/dm.c | 5 +++--
drivers/nvdimm/pmem.c | 8 +++++---
drivers/nvdimm/pmem.h | 5 ++++-
drivers/s390/block/dcssblk.c | 9 ++++++---
fs/dax.c | 9 +++++----
fs/fuse/dax.c | 4 ++--
fs/fuse/virtio_fs.c | 6 ++++--
include/linux/dax.h | 9 +++++++--
include/linux/device-mapper.h | 4 +++-
tools/testing/nvdimm/pmem-dax.c | 4 +++-
16 files changed, 61 insertions(+), 33 deletions(-)

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 0211e6f7b47a..5405eb553430 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -117,6 +117,7 @@ enum dax_device_flags {
* @dax_dev: a dax_device instance representing the logical memory range
* @pgoff: offset in pages from the start of the device to translate
* @nr_pages: number of consecutive pages caller can handle relative to @pfn
+ * @mode: indicator on normal access or recovery write
* @kaddr: output parameter that returns a virtual address mapping of pfn
* @pfn: output parameter that returns an absolute pfn translation of @pgoff
*
@@ -124,7 +125,7 @@ enum dax_device_flags {
* pages accessible at the device relative @pgoff.
*/
long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
- void **kaddr, pfn_t *pfn)
+ enum dax_access_mode mode, void **kaddr, pfn_t *pfn)
{
long avail;

@@ -138,7 +139,7 @@ long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
return -EINVAL;

avail = dax_dev->ops->direct_access(dax_dev, pgoff, nr_pages,
- kaddr, pfn);
+ mode, kaddr, pfn);
if (!avail)
return -ERANGE;
return min(avail, nr_pages);
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 76b486e4d2be..13e263299c9c 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -172,11 +172,12 @@ static struct dax_device *linear_dax_pgoff(struct dm_target *ti, pgoff_t *pgoff)
}

static long linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
struct dax_device *dax_dev = linear_dax_pgoff(ti, &pgoff);

- return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn);
+ return dax_direct_access(dax_dev, pgoff, nr_pages, mode, kaddr, pfn);
}

static int linear_dax_zero_page_range(struct dm_target *ti, pgoff_t pgoff,
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index c9d036d6bb2e..06bdbed65eb1 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -889,11 +889,12 @@ static struct dax_device *log_writes_dax_pgoff(struct dm_target *ti,
}

static long log_writes_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
struct dax_device *dax_dev = log_writes_dax_pgoff(ti, &pgoff);

- return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn);
+ return dax_direct_access(dax_dev, pgoff, nr_pages, mode, kaddr, pfn);
}

static int log_writes_dax_zero_page_range(struct dm_target *ti, pgoff_t pgoff,
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index c81d331d1afe..77d72900e997 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -315,11 +315,12 @@ static struct dax_device *stripe_dax_pgoff(struct dm_target *ti, pgoff_t *pgoff)
}

static long stripe_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
struct dax_device *dax_dev = stripe_dax_pgoff(ti, &pgoff);

- return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn);
+ return dax_direct_access(dax_dev, pgoff, nr_pages, mode, kaddr, pfn);
}

static int stripe_dax_zero_page_range(struct dm_target *ti, pgoff_t pgoff,
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 64dd0b34fcf4..8cd5184e62f0 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -10,6 +10,7 @@
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/bio.h>
+#include <linux/dax.h>

#define DM_MSG_PREFIX "target"

@@ -142,7 +143,8 @@ static void io_err_release_clone_rq(struct request *clone,
}

static long io_err_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
return -EIO;
}
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 5630b470ba42..d74c5a7a0ab4 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -286,7 +286,8 @@ static int persistent_memory_claim(struct dm_writecache *wc)

id = dax_read_lock();

- da = dax_direct_access(wc->ssd_dev->dax_dev, offset, p, &wc->memory_map, &pfn);
+ da = dax_direct_access(wc->ssd_dev->dax_dev, offset, p, DAX_ACCESS,
+ &wc->memory_map, &pfn);
if (da < 0) {
wc->memory_map = NULL;
r = da;
@@ -308,8 +309,8 @@ static int persistent_memory_claim(struct dm_writecache *wc)
i = 0;
do {
long daa;
- daa = dax_direct_access(wc->ssd_dev->dax_dev, offset + i, p - i,
- NULL, &pfn);
+ daa = dax_direct_access(wc->ssd_dev->dax_dev, offset + i,
+ p - i, DAX_ACCESS, NULL, &pfn);
if (daa <= 0) {
r = daa ? daa : -EINVAL;
goto err3;
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 82957bd460e8..9c452641c3d5 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1093,7 +1093,8 @@ static struct dm_target *dm_dax_get_live_target(struct mapped_device *md,
}

static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
struct mapped_device *md = dax_get_private(dax_dev);
sector_t sector = pgoff * PAGE_SECTORS;
@@ -1111,7 +1112,7 @@ static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
if (len < 1)
goto out;
nr_pages = min(len, nr_pages);
- ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn);
+ ret = ti->type->direct_access(ti, pgoff, nr_pages, mode, kaddr, pfn);

out:
dm_put_live_table(md, srcu_idx);
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 4aa17132a557..47f34c50f944 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -239,7 +239,8 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector,

/* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
__weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;

@@ -278,11 +279,12 @@ static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
}

static long pmem_dax_direct_access(struct dax_device *dax_dev,
- pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
+ pgoff_t pgoff, long nr_pages, enum dax_access_mode mode,
+ void **kaddr, pfn_t *pfn)
{
struct pmem_device *pmem = dax_get_private(dax_dev);

- return __pmem_direct_access(pmem, pgoff, nr_pages, kaddr, pfn);
+ return __pmem_direct_access(pmem, pgoff, nr_pages, mode, kaddr, pfn);
}

static const struct dax_operations pmem_dax_ops = {
diff --git a/drivers/nvdimm/pmem.h b/drivers/nvdimm/pmem.h
index 1f51a2361429..392b0b38acb9 100644
--- a/drivers/nvdimm/pmem.h
+++ b/drivers/nvdimm/pmem.h
@@ -8,6 +8,8 @@
#include <linux/pfn_t.h>
#include <linux/fs.h>

+enum dax_access_mode;
+
/* this definition is in it's own header for tools/testing/nvdimm to consume */
struct pmem_device {
/* One contiguous memory region per device */
@@ -28,7 +30,8 @@ struct pmem_device {
};

long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn);
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn);

#ifdef CONFIG_MEMORY_FAILURE
static inline bool test_and_clear_pmem_poison(struct page *page)
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index d614843caf6c..8d0d0eaa3059 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -32,7 +32,8 @@ static int dcssblk_open(struct block_device *bdev, fmode_t mode);
static void dcssblk_release(struct gendisk *disk, fmode_t mode);
static void dcssblk_submit_bio(struct bio *bio);
static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn);
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn);

static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";

@@ -50,7 +51,8 @@ static int dcssblk_dax_zero_page_range(struct dax_device *dax_dev,
long rc;
void *kaddr;

- rc = dax_direct_access(dax_dev, pgoff, nr_pages, &kaddr, NULL);
+ rc = dax_direct_access(dax_dev, pgoff, nr_pages, DAX_ACCESS,
+ &kaddr, NULL);
if (rc < 0)
return rc;
memset(kaddr, 0, nr_pages << PAGE_SHIFT);
@@ -927,7 +929,8 @@ __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,

static long
dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
struct dcssblk_dev_info *dev_info = dax_get_private(dax_dev);

diff --git a/fs/dax.c b/fs/dax.c
index 67a08a32fccb..ef3103107104 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -721,7 +721,8 @@ static int copy_cow_page_dax(struct vm_fault *vmf, const struct iomap_iter *iter
int id;

id = dax_read_lock();
- rc = dax_direct_access(iter->iomap.dax_dev, pgoff, 1, &kaddr, NULL);
+ rc = dax_direct_access(iter->iomap.dax_dev, pgoff, 1, DAX_ACCESS,
+ &kaddr, NULL);
if (rc < 0) {
dax_read_unlock(id);
return rc;
@@ -1013,7 +1014,7 @@ static int dax_iomap_pfn(const struct iomap *iomap, loff_t pos, size_t size,

id = dax_read_lock();
length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
- NULL, pfnp);
+ DAX_ACCESS, NULL, pfnp);
if (length < 0) {
rc = length;
goto out;
@@ -1122,7 +1123,7 @@ static int dax_memzero(struct dax_device *dax_dev, pgoff_t pgoff,
void *kaddr;
long ret;

- ret = dax_direct_access(dax_dev, pgoff, 1, &kaddr, NULL);
+ ret = dax_direct_access(dax_dev, pgoff, 1, DAX_ACCESS, &kaddr, NULL);
if (ret > 0) {
memset(kaddr + offset, 0, size);
dax_flush(dax_dev, kaddr + offset, size);
@@ -1247,7 +1248,7 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
}

map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
- &kaddr, NULL);
+ DAX_ACCESS, &kaddr, NULL);
if (map_len < 0) {
ret = map_len;
break;
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index d7d3a7f06862..10eb50cbf398 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -1241,8 +1241,8 @@ static int fuse_dax_mem_range_init(struct fuse_conn_dax *fcd)
INIT_DELAYED_WORK(&fcd->free_work, fuse_dax_free_mem_worker);

id = dax_read_lock();
- nr_pages = dax_direct_access(fcd->dev, 0, PHYS_PFN(dax_size), NULL,
- NULL);
+ nr_pages = dax_direct_access(fcd->dev, 0, PHYS_PFN(dax_size),
+ DAX_ACCESS, NULL, NULL);
dax_read_unlock(id);
if (nr_pages < 0) {
pr_debug("dax_direct_access() returned %ld\n", nr_pages);
diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index 86b7dbb6a0d4..8db53fa67359 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -752,7 +752,8 @@ static void virtio_fs_cleanup_vqs(struct virtio_device *vdev,
* offset.
*/
static long virtio_fs_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode,
+ void **kaddr, pfn_t *pfn)
{
struct virtio_fs *fs = dax_get_private(dax_dev);
phys_addr_t offset = PFN_PHYS(pgoff);
@@ -772,7 +773,8 @@ static int virtio_fs_zero_page_range(struct dax_device *dax_dev,
long rc;
void *kaddr;

- rc = dax_direct_access(dax_dev, pgoff, nr_pages, &kaddr, NULL);
+ rc = dax_direct_access(dax_dev, pgoff, nr_pages, DAX_ACCESS, &kaddr,
+ NULL);
if (rc < 0)
return rc;
memset(kaddr, 0, nr_pages << PAGE_SHIFT);
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 9fc5f99a0ae2..3f1339bce3c0 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -14,6 +14,11 @@ struct iomap_ops;
struct iomap_iter;
struct iomap;

+enum dax_access_mode {
+ DAX_ACCESS,
+ DAX_RECOVERY_WRITE,
+};
+
struct dax_operations {
/*
* direct_access: translate a device-relative
@@ -21,7 +26,7 @@ struct dax_operations {
* number of pages available for DAX at that pfn.
*/
long (*direct_access)(struct dax_device *, pgoff_t, long,
- void **, pfn_t *);
+ enum dax_access_mode, void **, pfn_t *);
/*
* Validate whether this device is usable as an fsdax backing
* device.
@@ -178,7 +183,7 @@ static inline void dax_read_unlock(int id)
bool dax_alive(struct dax_device *dax_dev);
void *dax_get_private(struct dax_device *dax_dev);
long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
- void **kaddr, pfn_t *pfn);
+ enum dax_access_mode mode, void **kaddr, pfn_t *pfn);
size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
size_t bytes, struct iov_iter *i);
size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
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);

diff --git a/tools/testing/nvdimm/pmem-dax.c b/tools/testing/nvdimm/pmem-dax.c
index af19c85558e7..c1ec099a3b1d 100644
--- a/tools/testing/nvdimm/pmem-dax.c
+++ b/tools/testing/nvdimm/pmem-dax.c
@@ -4,11 +4,13 @@
*/
#include "test/nfit_test.h"
#include <linux/blkdev.h>
+#include <linux/dax.h>
#include <pmem.h>
#include <nd.h>

long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ pfn_t *pfn)
{
resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;