| Message ID | 20200903152839.19040-1-colyli@suse.de (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Mike Snitzer |
| Headers | show |
| Series | [v2] dax: fix for do not print error message for non-persistent memory block device | expand |
> When calling __generic_fsdax_supported(), a dax-unsupported device may > not have dax_dev as NULL, e.g. the dax related code block is not enabled > by Kconfig. > > Therefore in __generic_fsdax_supported(), to check whether a device > supports DAX or not, the following order should be performed, > - If dax_dev pointer is NULL, it means the device driver explicitly > announce it doesn't support DAX. Then it is OK to directly return > false from __generic_fsdax_supported(). > - If dax_dev pointer is NOT NULL, it might be because the driver doesn't > support DAX and not explicitly initialize related data structure. Then > bdev_dax_supported() should be called for further check. > > IMHO if device driver desn't explicitly set its dax_dev pointer to NULL, > this is not a bug. Calling bdev_dax_supported() makes sure they can be > recognized as dax-unsupported eventually. > > This patch does the following change for the above purpose, > - if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { > + if (!dax_dev || !bdev_dax_supported(bdev, blocksize)) { > > > Fixes: c2affe920b0e ("dax: do not print error message for non-persistent memory block device") > Signed-off-by: Coly Li <colyli@suse.de> > Reviewed-and-Tested-by: Adrian Huang <ahuang12@lenovo.com> > Cc: Ira Weiny <ira.weiny@intel.com> > Cc: Jan Kara <jack@suse.com> > Cc: Mike Snitzer <snitzer@redhat.com> > Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> > Cc: Vishal Verma <vishal.l.verma@intel.com> > --- > Changelog: > v2: add Reviewed-and-Tested-by from Adrian Huang. > v1: initial version. > > drivers/dax/super.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/dax/super.c b/drivers/dax/super.c > index 32642634c1bb..e5767c83ea23 100644 > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -100,7 +100,7 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev, > return false; > } > > - if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { > + if (!dax_dev || !bdev_dax_supported(bdev, blocksize)) { > pr_debug("%s: error: dax unsupported by block device\n", > bdevname(bdev, buf)); > return false; > -- Looks good. Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
On Thu, Sep 03 2020 at 11:28am -0400, Coly Li <colyli@suse.de> wrote: > When calling __generic_fsdax_supported(), a dax-unsupported device may > not have dax_dev as NULL, e.g. the dax related code block is not enabled > by Kconfig. > > Therefore in __generic_fsdax_supported(), to check whether a device > supports DAX or not, the following order should be performed, > - If dax_dev pointer is NULL, it means the device driver explicitly > announce it doesn't support DAX. Then it is OK to directly return > false from __generic_fsdax_supported(). > - If dax_dev pointer is NOT NULL, it might be because the driver doesn't > support DAX and not explicitly initialize related data structure. Then > bdev_dax_supported() should be called for further check. > > IMHO if device driver desn't explicitly set its dax_dev pointer to NULL, > this is not a bug. Calling bdev_dax_supported() makes sure they can be > recognized as dax-unsupported eventually. > > This patch does the following change for the above purpose, > - if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { > + if (!dax_dev || !bdev_dax_supported(bdev, blocksize)) { Don't think I've ever seen a one-liner fix document the diff in its patch header. Really no need for that. > Fixes: c2affe920b0e ("dax: do not print error message for non-persistent memory block device") > Signed-off-by: Coly Li <colyli@suse.de> > Reviewed-and-Tested-by: Adrian Huang <ahuang12@lenovo.com> > Cc: Ira Weiny <ira.weiny@intel.com> > Cc: Jan Kara <jack@suse.com> > Cc: Mike Snitzer <snitzer@redhat.com> > Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> > Cc: Vishal Verma <vishal.l.verma@intel.com> Thanks for fixing this, Reviewed-by: Mike Snitzer <snitzer@redhat.com> > --- > Changelog: > v2: add Reviewed-and-Tested-by from Adrian Huang. > v1: initial version. > > drivers/dax/super.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/dax/super.c b/drivers/dax/super.c > index 32642634c1bb..e5767c83ea23 100644 > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -100,7 +100,7 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev, > return false; > } > > - if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { > + if (!dax_dev || !bdev_dax_supported(bdev, blocksize)) { > pr_debug("%s: error: dax unsupported by block device\n", > bdevname(bdev, buf)); > return false; > -- > 2.26.2 > -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
On 2020/9/4 00:00, Mike Snitzer wrote: > On Thu, Sep 03 2020 at 11:28am -0400, > Coly Li <colyli@suse.de> wrote: > >> When calling __generic_fsdax_supported(), a dax-unsupported device may >> not have dax_dev as NULL, e.g. the dax related code block is not enabled >> by Kconfig. >> >> Therefore in __generic_fsdax_supported(), to check whether a device >> supports DAX or not, the following order should be performed, >> - If dax_dev pointer is NULL, it means the device driver explicitly >> announce it doesn't support DAX. Then it is OK to directly return >> false from __generic_fsdax_supported(). >> - If dax_dev pointer is NOT NULL, it might be because the driver doesn't >> support DAX and not explicitly initialize related data structure. Then >> bdev_dax_supported() should be called for further check. >> >> IMHO if device driver desn't explicitly set its dax_dev pointer to NULL, >> this is not a bug. Calling bdev_dax_supported() makes sure they can be >> recognized as dax-unsupported eventually. >> >> This patch does the following change for the above purpose, >> - if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { >> + if (!dax_dev || !bdev_dax_supported(bdev, blocksize)) { > > Don't think I've ever seen a one-liner fix document the diff in its > patch header. Really no need for that. > Oops, I just see this comment when I maximum my email client window now. OK, I will post a v4 version to remove the above diff-like style comment. Coly Li -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 32642634c1bb..e5767c83ea23 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -100,7 +100,7 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev, return false; } - if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { + if (!dax_dev || !bdev_dax_supported(bdev, blocksize)) { pr_debug("%s: error: dax unsupported by block device\n", bdevname(bdev, buf)); return false;
When calling __generic_fsdax_supported(), a dax-unsupported device may not have dax_dev as NULL, e.g. the dax related code block is not enabled by Kconfig. Therefore in __generic_fsdax_supported(), to check whether a device supports DAX or not, the following order should be performed, - If dax_dev pointer is NULL, it means the device driver explicitly announce it doesn't support DAX. Then it is OK to directly return false from __generic_fsdax_supported(). - If dax_dev pointer is NOT NULL, it might be because the driver doesn't support DAX and not explicitly initialize related data structure. Then bdev_dax_supported() should be called for further check. IMHO if device driver desn't explicitly set its dax_dev pointer to NULL, this is not a bug. Calling bdev_dax_supported() makes sure they can be recognized as dax-unsupported eventually. This patch does the following change for the above purpose, - if (!dax_dev && !bdev_dax_supported(bdev, blocksize)) { + if (!dax_dev || !bdev_dax_supported(bdev, blocksize)) { Fixes: c2affe920b0e ("dax: do not print error message for non-persistent memory block device") Signed-off-by: Coly Li <colyli@suse.de> Reviewed-and-Tested-by: Adrian Huang <ahuang12@lenovo.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jan Kara <jack@suse.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Vishal Verma <vishal.l.verma@intel.com> --- Changelog: v2: add Reviewed-and-Tested-by from Adrian Huang. v1: initial version. drivers/dax/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)