Re: [PATCH v2 04/12] axonrom: Generate uevent after attribute available
On Thu, 06/30 15:10, Dan Williams wrote:
> On Wed, Jun 29, 2016 at 6:59 PM, Fam Zheng wrote:
> > It is documented that KOBJ_ADD should be generated after the object's
> > attributes and children are ready. We can achieve this with the new
> > disk_gen_uevents interface.
> >
> > Signed-off-by: Fam Zheng
> > ---
> > arch/powerpc/sysdev/axonram.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
> > index 4efd69b..27e7175 100644
> > --- a/arch/powerpc/sysdev/axonram.c
> > +++ b/arch/powerpc/sysdev/axonram.c
> > @@ -238,7 +238,7 @@ static int axon_ram_probe(struct platform_device
> > *device)
> > set_capacity(bank->disk, bank->size >> AXON_RAM_SECTOR_SHIFT);
> > blk_queue_make_request(bank->disk->queue, axon_ram_make_request);
> > blk_queue_logical_block_size(bank->disk->queue,
> > AXON_RAM_SECTOR_SIZE);
> > - add_disk(bank->disk, true);
> > + add_disk(bank->disk, false);
> >
> > bank->irq_id = irq_of_parse_and_map(device->dev.of_node, 0);
> > if (bank->irq_id == NO_IRQ) {
> > @@ -262,6 +262,7 @@ static int axon_ram_probe(struct platform_device
> > *device)
> > rc = -EFAULT;
> > goto failed;
> > }
> > + disk_gen_uevents(bank->disk);
>
> I assume you are doing this after:
>
>rc = device_create_file(&device->dev, &dev_attr_ecc);
>
> ...so that userspace gets notified of the new attribute, but this
> attribute is on the parent device, not the disk itself. Instead I
> think this attribute should simply be registered before the call to
> add_disk(). Then the KOBJ_ADD event for the disk comes after the
> attribute is available. It's still not a clean fit, because userspace
> should not be expecting a child device uevent to signal new attributes
> available on the parent.
Yes you are right, this patch is a mistake. Moving to before add_disk makes
sense to me.
Thanks for taking a look!
Fam
Re: [PATCH v2 04/12] axonrom: Generate uevent after attribute available
On Wed, Jun 29, 2016 at 6:59 PM, Fam Zheng wrote:
> It is documented that KOBJ_ADD should be generated after the object's
> attributes and children are ready. We can achieve this with the new
> disk_gen_uevents interface.
>
> Signed-off-by: Fam Zheng
> ---
> arch/powerpc/sysdev/axonram.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
> index 4efd69b..27e7175 100644
> --- a/arch/powerpc/sysdev/axonram.c
> +++ b/arch/powerpc/sysdev/axonram.c
> @@ -238,7 +238,7 @@ static int axon_ram_probe(struct platform_device *device)
> set_capacity(bank->disk, bank->size >> AXON_RAM_SECTOR_SHIFT);
> blk_queue_make_request(bank->disk->queue, axon_ram_make_request);
> blk_queue_logical_block_size(bank->disk->queue, AXON_RAM_SECTOR_SIZE);
> - add_disk(bank->disk, true);
> + add_disk(bank->disk, false);
>
> bank->irq_id = irq_of_parse_and_map(device->dev.of_node, 0);
> if (bank->irq_id == NO_IRQ) {
> @@ -262,6 +262,7 @@ static int axon_ram_probe(struct platform_device *device)
> rc = -EFAULT;
> goto failed;
> }
> + disk_gen_uevents(bank->disk);
I assume you are doing this after:
rc = device_create_file(&device->dev, &dev_attr_ecc);
...so that userspace gets notified of the new attribute, but this
attribute is on the parent device, not the disk itself. Instead I
think this attribute should simply be registered before the call to
add_disk(). Then the KOBJ_ADD event for the disk comes after the
attribute is available. It's still not a clean fit, because userspace
should not be expecting a child device uevent to signal new attributes
available on the parent.
[PATCH v2 04/12] axonrom: Generate uevent after attribute available
It is documented that KOBJ_ADD should be generated after the object's
attributes and children are ready. We can achieve this with the new
disk_gen_uevents interface.
Signed-off-by: Fam Zheng
---
arch/powerpc/sysdev/axonram.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
index 4efd69b..27e7175 100644
--- a/arch/powerpc/sysdev/axonram.c
+++ b/arch/powerpc/sysdev/axonram.c
@@ -238,7 +238,7 @@ static int axon_ram_probe(struct platform_device *device)
set_capacity(bank->disk, bank->size >> AXON_RAM_SECTOR_SHIFT);
blk_queue_make_request(bank->disk->queue, axon_ram_make_request);
blk_queue_logical_block_size(bank->disk->queue, AXON_RAM_SECTOR_SIZE);
- add_disk(bank->disk, true);
+ add_disk(bank->disk, false);
bank->irq_id = irq_of_parse_and_map(device->dev.of_node, 0);
if (bank->irq_id == NO_IRQ) {
@@ -262,6 +262,7 @@ static int axon_ram_probe(struct platform_device *device)
rc = -EFAULT;
goto failed;
}
+ disk_gen_uevents(bank->disk);
azfs_minor += bank->disk->minors;
--
2.9.0
