Re: [GIT preview] for-6.3/cxl-ram-region

[Gregory Price <gregory.price@memverge.com>]

On Wed, Jan 25, 2023 at 10:25:42PM -0800, Dan Williams wrote:
> There are still some sharp edges on this patchset, like the missing
> device-dax hookup, but it is likely enough to show the direction and
> unblock other testing. Specifically I want to see how this fares with
> Greg's recent volatile region provisioning in QEMU.
> 
> I am hoping to have those last bits ironed out before the end of the
> week. Note that this topic branch will rebase so do not base any
> work beyond proof-of-concept on top of it.
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git/log/?h=for-6.3/cxl-ram-region


Testing this out now.  Pulled it on top of the recent DOE updates so
this build error may be related (or not).  But it does look like it's
just a naming collision.




lib/stackinit_kunit.c:34:13: error: conflicting types for ‘range_contains’; have ‘bool(char *, size_t,  char *, size_t)’ {aka ‘_Bool(char *, long unsigned int,  char *, long unsigned int)’}
   34 | static bool range_contains(char *haystack_start, size_t haystack_size,
      |             ^~~~~~~~~~~~~~
In file included from ./arch/x86/include/asm/page.h:21,
                 from ./arch/x86/include/asm/thread_info.h:12,
                 from ./include/linux/thread_info.h:60,
                 from ./arch/x86/include/asm/preempt.h:9,
                 from ./include/linux/preempt.h:78,
                 from ./include/linux/spinlock.h:56,
                 from ./include/linux/kref.h:16,
                 from ./include/kunit/test.h:21,
                 from lib/stackinit_kunit.c:14:
./include/linux/range.h:16:20: note: previous definition of ‘range_contains’ with type ‘bool(struct range *, struct range *)’ {aka ‘_Bool(struct range *, struct range *)’}
   16 | static inline bool range_contains(struct range *r1, struct range *r2)
      |


Was just going recommend renaming contains to envelops for a quick hack
to fix the build issue.

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 62d5bafd02d1..f781e46a825e 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -230,7 +230,7 @@ static int dvsec_range_allowed(struct device *dev, void *arg)
        if (!(cxld->flags & CXL_DECODER_F_RAM))
                return 0;

-       return range_contains(&cxld->hpa_range, dev_range);
+       return range_envelops(&cxld->hpa_range, dev_range);
 }

 static void disable_hdm(void *_cxlhdm)
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 73d4d451386b..c0cb828b86e3 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -1381,7 +1381,7 @@ static int decoder_match_range(struct device *dev, void *data)
                return 0;

        cxlsd = to_cxl_switch_decoder(dev);
-       return range_contains(&cxlsd->cxld.hpa_range, &cxled->cxld.hpa_range);
+       return range_envelops(&cxlsd->cxld.hpa_range, &cxled->cxld.hpa_range);
 }

 static void find_positions(const struct cxl_switch_decoder *cxlsd,
@@ -2350,7 +2350,7 @@ static int match_decoder_by_range(struct device *dev, void *data)

        cxlrd = to_cxl_root_decoder(dev);
        r1 = &cxlrd->cxlsd.cxld.hpa_range;
-       return range_contains(r1, r2);
+       return range_envelops(r1, r2);
 }

 static int match_region_by_range(struct device *dev, void *data)
diff --git a/include/linux/range.h b/include/linux/range.h
index 7efb6a9b069b..8ad8c036d027 100644
--- a/include/linux/range.h
+++ b/include/linux/range.h
@@ -13,7 +13,7 @@ static inline u64 range_len(const struct range *range)
        return range->end - range->start + 1;
 }

-static inline bool range_contains(struct range *r1, struct range *r2)
+static inline bool range_envelops(struct range *r1, struct range *r2)
 {
        return r1->start <= r2->start && r1->end >= r2->end;
 }