Setup a dax_dev to have the same lifetime as the dcssblk block device
and add a ->direct_access() method that is equivalent to
dcssblk_direct_access(). Once fs/dax.c has been converted to use
dax_operations the old dcssblk_direct_access() will be removed.
Reported-by: Gerald Schaefer <[email protected]>
Signed-off-by: Dan Williams <[email protected]>
---
Changes since v2:
* fix return code in the alloc_dax() failure case (Gerald)
* assign dax_dev to dev_info and kill local variable (Gerald)
drivers/s390/block/Kconfig | 1 +
drivers/s390/block/dcssblk.c | 55 +++++++++++++++++++++++++++++++++++-------
2 files changed, 47 insertions(+), 9 deletions(-)
diff --git a/drivers/s390/block/Kconfig b/drivers/s390/block/Kconfig
index 4a3b62326183..0acb8c2f9475 100644
--- a/drivers/s390/block/Kconfig
+++ b/drivers/s390/block/Kconfig
@@ -14,6 +14,7 @@ config BLK_DEV_XPRAM
config DCSSBLK
def_tristate m
+ select DAX
prompt "DCSSBLK support"
depends on S390 && BLOCK
help
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 415d10a67b7a..dc84cfd4e438 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -18,6 +18,7 @@
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/pfn_t.h>
+#include <linux/dax.h>
#include <asm/extmem.h>
#include <asm/io.h>
@@ -30,8 +31,10 @@ 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_make_request(struct request_queue *q,
struct bio *bio);
-static long dcssblk_direct_access(struct block_device *bdev, sector_t secnum,
+static long dcssblk_blk_direct_access(struct block_device *bdev, sector_t secnum,
void **kaddr, pfn_t *pfn, long size);
+static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
+ long nr_pages, void **kaddr, pfn_t *pfn);
static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
@@ -40,7 +43,11 @@ static const struct block_device_operations dcssblk_devops = {
.owner = THIS_MODULE,
.open = dcssblk_open,
.release = dcssblk_release,
- .direct_access = dcssblk_direct_access,
+ .direct_access = dcssblk_blk_direct_access,
+};
+
+static const struct dax_operations dcssblk_dax_ops = {
+ .direct_access = dcssblk_dax_direct_access,
};
struct dcssblk_dev_info {
@@ -57,6 +64,7 @@ struct dcssblk_dev_info {
struct request_queue *dcssblk_queue;
int num_of_segments;
struct list_head seg_list;
+ struct dax_device *dax_dev;
};
struct segment_info {
@@ -389,6 +397,8 @@ dcssblk_shared_store(struct device *dev, struct device_attribute *attr, const ch
}
list_del(&dev_info->lh);
+ kill_dax(dev_info->dax_dev);
+ put_dax(dev_info->dax_dev);
del_gendisk(dev_info->gd);
blk_cleanup_queue(dev_info->dcssblk_queue);
dev_info->gd->queue = NULL;
@@ -654,6 +664,13 @@ dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char
if (rc)
goto put_dev;
+ dev_info->dax_dev = alloc_dax(dev_info, dev_info->gd->disk_name,
+ &dcssblk_dax_ops);
+ if (!dev_info->dax_dev) {
+ rc = -ENOMEM;
+ goto put_dev;
+ }
+
get_device(&dev_info->dev);
device_add_disk(&dev_info->dev, dev_info->gd);
@@ -752,6 +769,8 @@ dcssblk_remove_store(struct device *dev, struct device_attribute *attr, const ch
}
list_del(&dev_info->lh);
+ kill_dax(dev_info->dax_dev);
+ put_dax(dev_info->dax_dev);
del_gendisk(dev_info->gd);
blk_cleanup_queue(dev_info->dcssblk_queue);
dev_info->gd->queue = NULL;
@@ -883,21 +902,39 @@ dcssblk_make_request(struct request_queue *q, struct bio *bio)
}
static long
-dcssblk_direct_access (struct block_device *bdev, sector_t secnum,
+__dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,
+ long nr_pages, void **kaddr, pfn_t *pfn)
+{
+ resource_size_t offset = pgoff * PAGE_SIZE;
+ unsigned long dev_sz;
+
+ dev_sz = dev_info->end - dev_info->start + 1;
+ *kaddr = (void *) dev_info->start + offset;
+ *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), PFN_DEV);
+
+ return (dev_sz - offset) / PAGE_SIZE;
+}
+
+static long
+dcssblk_blk_direct_access(struct block_device *bdev, sector_t secnum,
void **kaddr, pfn_t *pfn, long size)
{
struct dcssblk_dev_info *dev_info;
- unsigned long offset, dev_sz;
dev_info = bdev->bd_disk->private_data;
if (!dev_info)
return -ENODEV;
- dev_sz = dev_info->end - dev_info->start + 1;
- offset = secnum * 512;
- *kaddr = (void *) dev_info->start + offset;
- *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), PFN_DEV);
+ return __dcssblk_direct_access(dev_info, PHYS_PFN(secnum * 512),
+ PHYS_PFN(size), kaddr, pfn) * PAGE_SIZE;
+}
+
+static long
+dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
+ long nr_pages, void **kaddr, pfn_t *pfn)
+{
+ struct dcssblk_dev_info *dev_info = dax_get_private(dax_dev);
- return dev_sz - offset;
+ return __dcssblk_direct_access(dev_info, pgoff, nr_pages, kaddr, pfn);
}
static void
Hi Dan,
[auto build test ERROR on linus/master]
[also build test ERROR on v4.11-rc7 next-20170419]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Dan-Williams/dcssblk-add-dax_operations-support/20170420-090408
config: s390-defconfig (attached as .config)
compiler: s390x-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=s390
All error/warnings (new ones prefixed by >>):
>> drivers/s390/block/dcssblk.c:36:46: warning: 'struct dax_device' declared inside parameter list will not be visible outside of this definition or declaration
static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
^~~~~~~~~~
>> drivers/s390/block/dcssblk.c:49:21: error: variable 'dcssblk_dax_ops' has initializer but incomplete type
static const struct dax_operations dcssblk_dax_ops = {
^~~~~~~~~~~~~~
>> drivers/s390/block/dcssblk.c:50:2: error: unknown field 'direct_access' specified in initializer
.direct_access = dcssblk_dax_direct_access,
^
>> drivers/s390/block/dcssblk.c:50:19: warning: excess elements in struct initializer
.direct_access = dcssblk_dax_direct_access,
^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/s390/block/dcssblk.c:50:19: note: (near initialization for 'dcssblk_dax_ops')
drivers/s390/block/dcssblk.c: In function 'dcssblk_shared_store':
>> drivers/s390/block/dcssblk.c:400:2: error: implicit declaration of function 'kill_dax' [-Werror=implicit-function-declaration]
kill_dax(dev_info->dax_dev);
^~~~~~~~
>> drivers/s390/block/dcssblk.c:401:2: error: implicit declaration of function 'put_dax' [-Werror=implicit-function-declaration]
put_dax(dev_info->dax_dev);
^~~~~~~
drivers/s390/block/dcssblk.c: In function 'dcssblk_add_store':
>> drivers/s390/block/dcssblk.c:667:22: error: implicit declaration of function 'alloc_dax' [-Werror=implicit-function-declaration]
dev_info->dax_dev = alloc_dax(dev_info, dev_info->gd->disk_name,
^~~~~~~~~
>> drivers/s390/block/dcssblk.c:667:20: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
dev_info->dax_dev = alloc_dax(dev_info, dev_info->gd->disk_name,
^
drivers/s390/block/dcssblk.c: At top level:
drivers/s390/block/dcssblk.c:932:1: error: conflicting types for 'dcssblk_dax_direct_access'
dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/s390/block/dcssblk.c:36:13: note: previous declaration of 'dcssblk_dax_direct_access' was here
static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/s390/block/dcssblk.c: In function 'dcssblk_dax_direct_access':
>> drivers/s390/block/dcssblk.c:935:38: error: implicit declaration of function 'dax_get_private' [-Werror=implicit-function-declaration]
struct dcssblk_dev_info *dev_info = dax_get_private(dax_dev);
^~~~~~~~~~~~~~~
>> drivers/s390/block/dcssblk.c:935:38: warning: initialization makes pointer from integer without a cast [-Wint-conversion]
drivers/s390/block/dcssblk.c: At top level:
>> drivers/s390/block/dcssblk.c:49:36: error: storage size of 'dcssblk_dax_ops' isn't known
static const struct dax_operations dcssblk_dax_ops = {
^~~~~~~~~~~~~~~
drivers/s390/block/dcssblk.c:36:13: warning: 'dcssblk_dax_direct_access' used but never defined
static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/s390/block/dcssblk.c:932:1: warning: 'dcssblk_dax_direct_access' defined but not used [-Wunused-function]
dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
^~~~~~~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/dcssblk_dax_ops +49 drivers/s390/block/dcssblk.c
30 static int dcssblk_open(struct block_device *bdev, fmode_t mode);
31 static void dcssblk_release(struct gendisk *disk, fmode_t mode);
32 static blk_qc_t dcssblk_make_request(struct request_queue *q,
33 struct bio *bio);
34 static long dcssblk_blk_direct_access(struct block_device *bdev, sector_t secnum,
35 void **kaddr, pfn_t *pfn, long size);
> 36 static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
37 long nr_pages, void **kaddr, pfn_t *pfn);
38
39 static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
40
41 static int dcssblk_major;
42 static const struct block_device_operations dcssblk_devops = {
43 .owner = THIS_MODULE,
44 .open = dcssblk_open,
45 .release = dcssblk_release,
46 .direct_access = dcssblk_blk_direct_access,
47 };
48
> 49 static const struct dax_operations dcssblk_dax_ops = {
> 50 .direct_access = dcssblk_dax_direct_access,
51 };
52
53 struct dcssblk_dev_info {
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
On Wed, 19 Apr 2017 15:32:38 -0700
Dan Williams <[email protected]> wrote:
> Setup a dax_dev to have the same lifetime as the dcssblk block device
> and add a ->direct_access() method that is equivalent to
> dcssblk_direct_access(). Once fs/dax.c has been converted to use
> dax_operations the old dcssblk_direct_access() will be removed.
>
> Reported-by: Gerald Schaefer <[email protected]>
> Signed-off-by: Dan Williams <[email protected]>
> ---
> Changes since v2:
> * fix return code in the alloc_dax() failure case (Gerald)
> * assign dax_dev to dev_info and kill local variable (Gerald)
>
> drivers/s390/block/Kconfig | 1 +
> drivers/s390/block/dcssblk.c | 55 +++++++++++++++++++++++++++++++++++-------
> 2 files changed, 47 insertions(+), 9 deletions(-)
Acked-by: Gerald Schaefer <[email protected]>