Hi all,
this series first clarifies how to use fsdax in the Kconfig help a bit,
and then untangles the code path that checks if fsdax is supported.
Changes since v1:
- improve the FS_DAX Kconfig help text further
- write a proper commit log for a patch missing it
Diffstat
drivers/dax/super.c | 191 +++++++++++++++++++-------------------------------
drivers/md/dm-table.c | 9 --
drivers/md/dm.c | 2
fs/Kconfig | 21 ++++-
fs/ext2/super.c | 3
fs/ext4/super.c | 3
fs/xfs/xfs_super.c | 16 +++-
include/linux/dax.h | 41 +---------
8 files changed, 117 insertions(+), 169 deletions(-)
The recent block layer refactoring broke the way how the pmem driver
abused device_add_disk. Fix this by properly passing the attribute groups
to device_add_disk.
Fixes: 52b85909f85d ("block: fold register_disk into device_add_disk")
Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ira Weiny <[email protected]>
Reviewed-by: Dan Williams <[email protected]>
---
drivers/nvdimm/pmem.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 72de88ff0d30d..ef4950f808326 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -380,7 +380,6 @@ static int pmem_attach_disk(struct device *dev,
struct nd_pfn_sb *pfn_sb;
struct pmem_device *pmem;
struct request_queue *q;
- struct device *gendev;
struct gendisk *disk;
void *addr;
int rc;
@@ -489,10 +488,8 @@ static int pmem_attach_disk(struct device *dev,
}
dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
pmem->dax_dev = dax_dev;
- gendev = disk_to_dev(disk);
- gendev->groups = pmem_attribute_groups;
- device_add_disk(dev, disk, NULL);
+ device_add_disk(dev, disk, pmem_attribute_groups);
if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
return -ENOMEM;
--
2.30.2
dax_attribute_group is only used by the pmem driver, and can avoid the
completely pointless lookup by the disk name if moved there. This
leaves just a single caller of dax_get_by_host, so move dax_get_by_host
into the same ifdef block as that caller.
Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Dan Williams <[email protected]>
---
drivers/dax/super.c | 100 ++++++++----------------------------------
drivers/nvdimm/pmem.c | 43 ++++++++++++++++++
include/linux/dax.h | 2 -
3 files changed, 61 insertions(+), 84 deletions(-)
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index fc89e91beea7c..b882cf8106ea3 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -63,6 +63,24 @@ static int dax_host_hash(const char *host)
return hashlen_hash(hashlen_string("DAX", host)) % DAX_HASH_SIZE;
}
+#ifdef CONFIG_BLOCK
+#include <linux/blkdev.h>
+
+int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
+ pgoff_t *pgoff)
+{
+ sector_t start_sect = bdev ? get_start_sect(bdev) : 0;
+ phys_addr_t phys_off = (start_sect + sector) * 512;
+
+ if (pgoff)
+ *pgoff = PHYS_PFN(phys_off);
+ if (phys_off % PAGE_SIZE || size % PAGE_SIZE)
+ return -EINVAL;
+ return 0;
+}
+EXPORT_SYMBOL(bdev_dax_pgoff);
+
+#if IS_ENABLED(CONFIG_FS_DAX)
/**
* dax_get_by_host() - temporary lookup mechanism for filesystem-dax
* @host: alternate name for the device registered by a dax driver
@@ -94,24 +112,6 @@ static struct dax_device *dax_get_by_host(const char *host)
return found;
}
-#ifdef CONFIG_BLOCK
-#include <linux/blkdev.h>
-
-int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,
- pgoff_t *pgoff)
-{
- sector_t start_sect = bdev ? get_start_sect(bdev) : 0;
- phys_addr_t phys_off = (start_sect + sector) * 512;
-
- if (pgoff)
- *pgoff = PHYS_PFN(phys_off);
- if (phys_off % PAGE_SIZE || size % PAGE_SIZE)
- return -EINVAL;
- return 0;
-}
-EXPORT_SYMBOL(bdev_dax_pgoff);
-
-#if IS_ENABLED(CONFIG_FS_DAX)
struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
{
if (!blk_queue_dax(bdev->bd_disk->queue))
@@ -231,70 +231,6 @@ enum dax_device_flags {
DAXDEV_SYNC,
};
-static ssize_t write_cache_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct dax_device *dax_dev = dax_get_by_host(dev_name(dev));
- ssize_t rc;
-
- WARN_ON_ONCE(!dax_dev);
- if (!dax_dev)
- return -ENXIO;
-
- rc = sprintf(buf, "%d\n", !!dax_write_cache_enabled(dax_dev));
- put_dax(dax_dev);
- return rc;
-}
-
-static ssize_t write_cache_store(struct device *dev,
- struct device_attribute *attr, const char *buf, size_t len)
-{
- bool write_cache;
- int rc = strtobool(buf, &write_cache);
- struct dax_device *dax_dev = dax_get_by_host(dev_name(dev));
-
- WARN_ON_ONCE(!dax_dev);
- if (!dax_dev)
- return -ENXIO;
-
- if (rc)
- len = rc;
- else
- dax_write_cache(dax_dev, write_cache);
-
- put_dax(dax_dev);
- return len;
-}
-static DEVICE_ATTR_RW(write_cache);
-
-static umode_t dax_visible(struct kobject *kobj, struct attribute *a, int n)
-{
- struct device *dev = container_of(kobj, typeof(*dev), kobj);
- struct dax_device *dax_dev = dax_get_by_host(dev_name(dev));
-
- WARN_ON_ONCE(!dax_dev);
- if (!dax_dev)
- return 0;
-
-#ifndef CONFIG_ARCH_HAS_PMEM_API
- if (a == &dev_attr_write_cache.attr)
- return 0;
-#endif
- return a->mode;
-}
-
-static struct attribute *dax_attributes[] = {
- &dev_attr_write_cache.attr,
- NULL,
-};
-
-struct attribute_group dax_attribute_group = {
- .name = "dax",
- .attrs = dax_attributes,
- .is_visible = dax_visible,
-};
-EXPORT_SYMBOL_GPL(dax_attribute_group);
-
/**
* dax_direct_access() - translate a device pgoff to an absolute pfn
* @dax_dev: a dax_device instance representing the logical memory range
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index ef4950f808326..bbeb3f46db157 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -328,6 +328,49 @@ static const struct dax_operations pmem_dax_ops = {
.zero_page_range = pmem_dax_zero_page_range,
};
+static ssize_t write_cache_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pmem_device *pmem = dev_to_disk(dev)->private_data;
+
+ return sprintf(buf, "%d\n", !!dax_write_cache_enabled(pmem->dax_dev));
+}
+
+static ssize_t write_cache_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t len)
+{
+ struct pmem_device *pmem = dev_to_disk(dev)->private_data;
+ bool write_cache;
+ int rc;
+
+ rc = strtobool(buf, &write_cache);
+ if (rc)
+ return rc;
+ dax_write_cache(pmem->dax_dev, write_cache);
+ return len;
+}
+static DEVICE_ATTR_RW(write_cache);
+
+static umode_t dax_visible(struct kobject *kobj, struct attribute *a, int n)
+{
+#ifndef CONFIG_ARCH_HAS_PMEM_API
+ if (a == &dev_attr_write_cache.attr)
+ return 0;
+#endif
+ return a->mode;
+}
+
+static struct attribute *dax_attributes[] = {
+ &dev_attr_write_cache.attr,
+ NULL,
+};
+
+static const struct attribute_group dax_attribute_group = {
+ .name = "dax",
+ .attrs = dax_attributes,
+ .is_visible = dax_visible,
+};
+
static const struct attribute_group *pmem_attribute_groups[] = {
&dax_attribute_group,
NULL,
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 2619d94c308d4..8623caa673889 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -38,8 +38,6 @@ struct dax_operations {
int (*zero_page_range)(struct dax_device *, pgoff_t, size_t);
};
-extern struct attribute_group dax_attribute_group;
-
#if IS_ENABLED(CONFIG_DAX)
struct dax_device *alloc_dax(void *private, const char *host,
const struct dax_operations *ops, unsigned long flags);
--
2.30.2
The proper API is to pass the groups to device_add_disk, but the code
used to also allow groups being set before calling *add_disk. Warn
about that but keep the group pointer intact for now so that it can
be removed again after a grace period.
Fixes: 52b85909f85d ("block: fold register_disk into device_add_disk")
Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ira Weiny <[email protected]>
Reviewed-by: Dan Williams <[email protected]>
---
block/genhd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/block/genhd.c b/block/genhd.c
index 7b6e5e1cf9564..409cf608cc5bd 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -439,7 +439,8 @@ int device_add_disk(struct device *parent, struct gendisk *disk,
dev_set_uevent_suppress(ddev, 1);
ddev->parent = parent;
- ddev->groups = groups;
+ if (!WARN_ON_ONCE(ddev->groups))
+ ddev->groups = groups;
dev_set_name(ddev, "%s", disk->disk_name);
if (!(disk->flags & GENHD_FL_HIDDEN))
ddev->devt = MKDEV(disk->major, disk->first_minor);
--
2.30.2
On Wed, Sep 22, 2021 at 10:37 AM Christoph Hellwig <[email protected]> wrote:
>
> Hi all,
>
> this series first clarifies how to use fsdax in the Kconfig help a bit,
> and then untangles the code path that checks if fsdax is supported.
>
> Changes since v1:
> - improve the FS_DAX Kconfig help text further
> - write a proper commit log for a patch missing it
>
This looks like your send script picked up the wrong cover letter?
> Diffstat
> drivers/dax/super.c | 191 +++++++++++++++++++-------------------------------
> drivers/md/dm-table.c | 9 --
> drivers/md/dm.c | 2
> fs/Kconfig | 21 ++++-
> fs/ext2/super.c | 3
> fs/ext4/super.c | 3
> fs/xfs/xfs_super.c | 16 +++-
> include/linux/dax.h | 41 +---------
> 8 files changed, 117 insertions(+), 169 deletions(-)
On Wed, Sep 22, 2021 at 10:55:01AM -0700, Dan Williams wrote:
> This looks like your send script picked up the wrong cover letter?
Yes. Or the human running the script to be exact :)