[PATCH 2/6] dax: prepare dax_direct_access() API with DAXDEV_F_RECOVERY flag

From: Jane Chu
Date: Wed Oct 20 2021 - 20:12:33 EST

Prepare dax_direct_access() API with DAXDEV_F_RECOVERY flag
such that the API may perform device address translation
in spite of the presence of poison(s) in a given range.

Signed-off-by: Jane Chu <jane.chu@xxxxxxxxxx>
---
drivers/dax/super.c | 9 +++++----
drivers/md/dm-linear.c | 4 ++--
drivers/md/dm-log-writes.c | 5 +++--
drivers/md/dm-stripe.c | 4 ++--
drivers/md/dm-target.c | 2 +-
drivers/md/dm-writecache.c | 4 ++--
drivers/md/dm.c | 4 ++--
drivers/nvdimm/pmem.c | 7 ++++---
drivers/nvdimm/pmem.h | 2 +-
drivers/s390/block/dcssblk.c | 7 ++++---
fs/dax.c | 12 ++++++++----
fs/fuse/dax.c | 2 +-
fs/fuse/virtio_fs.c | 4 ++--
include/linux/dax.h | 7 +++++--
include/linux/device-mapper.h | 2 +-
tools/testing/nvdimm/pmem-dax.c | 2 +-
16 files changed, 44 insertions(+), 33 deletions(-)

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index fc89e91beea7..67093f1c3341 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -156,8 +156,8 @@ bool generic_fsdax_supported(struct dax_device *dax_dev,
}

id = dax_read_lock();
- len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn);
- len2 = dax_direct_access(dax_dev, pgoff_end, 1, &end_kaddr, &end_pfn);
+ len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn, 0);
+ len2 = dax_direct_access(dax_dev, pgoff_end, 1, &end_kaddr, &end_pfn, 0);

if (len < 1 || len2 < 1) {
pr_info("%pg: error: dax access failed (%ld)\n",
@@ -302,12 +302,13 @@ EXPORT_SYMBOL_GPL(dax_attribute_group);
* @nr_pages: number of consecutive pages caller can handle relative to @pfn
* @kaddr: output parameter that returns a virtual address mapping of pfn
* @pfn: output parameter that returns an absolute pfn translation of @pgoff
+ * @flags: indication whether on dax data recovery code path or not
*
* Return: negative errno if an error occurs, otherwise the number of
* 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)
+ void **kaddr, pfn_t *pfn, unsigned long flags)
{
long avail;

@@ -321,7 +322,7 @@ 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);
+ kaddr, pfn, flags);
if (!avail)
return -ERANGE;
return min(avail, nr_pages);
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 679b4c0a2eea..cb7c8518f02d 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -165,7 +165,7 @@ static int linear_iterate_devices(struct dm_target *ti,

#if IS_ENABLED(CONFIG_DAX_DRIVER)
static long linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, void **kaddr, pfn_t *pfn, unsigned long flags)
{
long ret;
struct linear_c *lc = ti->private;
@@ -177,7 +177,7 @@ static long linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
ret = bdev_dax_pgoff(bdev, dev_sector, nr_pages * PAGE_SIZE, &pgoff);
if (ret)
return ret;
- return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn);
+ return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn, flags);
}

static size_t linear_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff,
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index d93a4db23512..6d8b88dcce6c 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -950,7 +950,7 @@ static int log_dax(struct log_writes_c *lc, sector_t sector, size_t bytes,
}

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, void **kaddr, pfn_t *pfn, unsigned long flags)
{
struct log_writes_c *lc = ti->private;
sector_t sector = pgoff * PAGE_SECTORS;
@@ -959,7 +959,8 @@ static long log_writes_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
ret = bdev_dax_pgoff(lc->dev->bdev, sector, nr_pages * PAGE_SIZE, &pgoff);
if (ret)
return ret;
- return dax_direct_access(lc->dev->dax_dev, pgoff, nr_pages, kaddr, pfn);
+ return dax_direct_access(lc->dev->dax_dev, pgoff, nr_pages, kaddr, pfn,
+ flags);
}

static size_t log_writes_dax_copy_from_iter(struct dm_target *ti,
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 6660b6b53d5b..0a97d0472a0b 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -302,7 +302,7 @@ static int stripe_map(struct dm_target *ti, struct bio *bio)

#if IS_ENABLED(CONFIG_DAX_DRIVER)
static long stripe_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
- long nr_pages, void **kaddr, pfn_t *pfn)
+ long nr_pages, void **kaddr, pfn_t *pfn, unsigned long flags)
{
sector_t dev_sector, sector = pgoff * PAGE_SECTORS;
struct stripe_c *sc = ti->private;
@@ -319,7 +319,7 @@ static long stripe_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
ret = bdev_dax_pgoff(bdev, dev_sector, nr_pages * PAGE_SIZE, &pgoff);
if (ret)
return ret;
- return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn);
+ return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn, flags);
}

static size_t stripe_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff,
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 64dd0b34fcf4..431764b77528 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -142,7 +142,7 @@ 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, void **kaddr, pfn_t *pfn, unsigned long flags)
{
return -EIO;
}
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 18320444fb0a..c523cb911eca 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -286,7 +286,7 @@ 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, &wc->memory_map, &pfn, 0);
if (da < 0) {
wc->memory_map = NULL;
r = da;
@@ -309,7 +309,7 @@ static int persistent_memory_claim(struct dm_writecache *wc)
do {
long daa;
daa = dax_direct_access(wc->ssd_dev->dax_dev, offset + i, p - i,
- NULL, &pfn);
+ NULL, &pfn, 0);
if (daa <= 0) {
r = daa ? daa : -EINVAL;
goto err3;
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index a011d09cb0fa..e5a14abd45f9 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -998,7 +998,7 @@ 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, void **kaddr, pfn_t *pfn, unsigned long flags)
{
struct mapped_device *md = dax_get_private(dax_dev);
sector_t sector = pgoff * PAGE_SECTORS;
@@ -1016,7 +1016,7 @@ 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, kaddr, pfn, flags);

out:
dm_put_live_table(md, srcu_idx);
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 72de88ff0d30..b0b7fd40560e 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -256,7 +256,7 @@ 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, void **kaddr, pfn_t *pfn, unsigned long flags)
{
resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;

@@ -295,11 +295,12 @@ 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, void **kaddr, pfn_t *pfn,
+ unsigned long flags)
{
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, kaddr, pfn, flags);
}

/*
diff --git a/drivers/nvdimm/pmem.h b/drivers/nvdimm/pmem.h
index 59cfe13ea8a8..fb769b22777a 100644
--- a/drivers/nvdimm/pmem.h
+++ b/drivers/nvdimm/pmem.h
@@ -27,7 +27,7 @@ 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, void **kaddr, pfn_t *pfn, unsigned long flags);

#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 5be3d1c39a78..6ab2f9badc8d 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -32,7 +32,7 @@ static int dcssblk_open(struct block_device *bdev, fmode_t mode);
static void dcssblk_release(struct gendisk *disk, fmode_t mode);
static blk_qc_t 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, void **kaddr, pfn_t *pfn, unsigned long flags);

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

@@ -62,7 +62,7 @@ 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, &kaddr, NULL, 0);
if (rc < 0)
return rc;
memset(kaddr, 0, nr_pages << PAGE_SHIFT);
@@ -932,7 +932,8 @@ __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, void **kaddr, pfn_t *pfn,
+ unsigned long flags)
{
struct dcssblk_dev_info *dev_info = dax_get_private(dax_dev);

diff --git a/fs/dax.c b/fs/dax.c
index 01118de00011..f603a9ce7f20 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -722,7 +722,7 @@ static int copy_cow_page_dax(struct block_device *bdev, struct dax_device *dax_d
return rc;

id = dax_read_lock();
- rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr, NULL);
+ rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr, NULL, 0);
if (rc < 0) {
dax_read_unlock(id);
return rc;
@@ -1023,7 +1023,7 @@ static int dax_iomap_pfn(const struct iomap *iomap, loff_t pos, size_t size,
return rc;
id = dax_read_lock();
length = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(size),
- NULL, pfnp);
+ NULL, pfnp, 0);
if (length < 0) {
rc = length;
goto out;
@@ -1149,7 +1149,7 @@ s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
if (page_aligned)
rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1);
else
- rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL);
+ rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL, 0);
if (rc < 0) {
dax_read_unlock(id);
return rc;
@@ -1172,6 +1172,7 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
struct block_device *bdev = iomap->bdev;
struct dax_device *dax_dev = iomap->dax_dev;
loff_t end = pos + length, done = 0;
+ unsigned long dax_flag = 0;
ssize_t ret = 0;
size_t xfer;
int id;
@@ -1199,6 +1200,9 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
(end - 1) >> PAGE_SHIFT);
}

+ if (iomi->flags & IOMAP_RECOVERY)
+ dax_flag |= DAXDEV_F_RECOVERY;
+
id = dax_read_lock();
while (pos < end) {
unsigned offset = pos & (PAGE_SIZE - 1);
@@ -1218,7 +1222,7 @@ static loff_t dax_iomap_iter(const struct iomap_iter *iomi,
break;

map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size),
- &kaddr, NULL);
+ &kaddr, NULL, dax_flag);
if (map_len < 0) {
ret = map_len;
break;
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index 281d79f8b3d3..2c45b94647f1 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -1245,7 +1245,7 @@ static int fuse_dax_mem_range_init(struct fuse_conn_dax *fcd)

id = dax_read_lock();
nr_pages = dax_direct_access(fcd->dev, 0, PHYS_PFN(dax_size), NULL,
- NULL);
+ NULL, 0);
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 0ad89c6629d7..d201b6e8a190 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -739,7 +739,7 @@ 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, void **kaddr, pfn_t *pfn, unsigned long flags)
{
struct virtio_fs *fs = dax_get_private(dax_dev);
phys_addr_t offset = PFN_PHYS(pgoff);
@@ -773,7 +773,7 @@ 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, &kaddr, NULL, 0);
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 2619d94c308d..0044a5d87e5d 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -9,6 +9,9 @@
/* Flag for synchronous flush */
#define DAXDEV_F_SYNC (1UL << 0)

+/* Flag for DAX data recovery */
+#define DAXDEV_F_RECOVERY (1UL << 1)
+
typedef unsigned long dax_entry_t;

struct iomap_ops;
@@ -21,7 +24,7 @@ struct dax_operations {
* number of pages available for DAX at that pfn.
*/
long (*direct_access)(struct dax_device *, pgoff_t, long,
- void **, pfn_t *);
+ void **, pfn_t *, unsigned long);
/*
* Validate whether this device is usable as an fsdax backing
* device.
@@ -192,7 +195,7 @@ 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);
+ void **kaddr, pfn_t *pfn, unsigned long);
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 114553b487ef..307c29789332 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -146,7 +146,7 @@ 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, void **kaddr, pfn_t *pfn, unsigned long flags);
typedef size_t (*dm_dax_copy_iter_fn)(struct dm_target *ti, pgoff_t pgoff,
void *addr, size_t bytes, struct iov_iter *i);
typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff,
diff --git a/tools/testing/nvdimm/pmem-dax.c b/tools/testing/nvdimm/pmem-dax.c
index af19c85558e7..45dcfffe5575 100644
--- a/tools/testing/nvdimm/pmem-dax.c
+++ b/tools/testing/nvdimm/pmem-dax.c
@@ -8,7 +8,7 @@
#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, void **kaddr, pfn_t *pfn, unsigned long flags)
{
resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;

--
2.18.4