| Message ID | 20240130165255.212591-2-mathieu.desnoyers@efficios.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Introduce dcache_is_aliasing() to fix DAX regression | expand |
On Tue, Jan 30, 2024 at 11:52:48AM -0500, Mathieu Desnoyers wrote: > Introduce a new dax_is_supported() static inline to check whether the > architecture supports DAX. > > This replaces the following fs/Kconfig:FS_DAX dependency: > > depends on !(ARM || MIPS || SPARC) > > This is done in preparation for its use by each filesystem supporting > the dax mount option to validate whether dax is indeed supported. > > This is done in preparation for using dcache_is_aliasing() in a > following change which will properly support architectures which detect > dcache aliasing at runtime. > > Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches") > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Cc: linux-mm@kvack.org > Cc: linux-arch@vger.kernel.org > Cc: Dan Williams <dan.j.williams@intel.com> > Cc: Vishal Verma <vishal.l.verma@intel.com> > Cc: Dave Jiang <dave.jiang@intel.com> > Cc: Matthew Wilcox <willy@infradead.org> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Russell King <linux@armlinux.org.uk> > Cc: nvdimm@lists.linux.dev > Cc: linux-cxl@vger.kernel.org > Cc: linux-fsdevel@vger.kernel.org > --- > fs/Kconfig | 1 - > include/linux/dax.h | 10 ++++++++++ > 2 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/fs/Kconfig b/fs/Kconfig > index 42837617a55b..e5efdb3b276b 100644 > --- a/fs/Kconfig > +++ b/fs/Kconfig > @@ -56,7 +56,6 @@ endif # BLOCK > config FS_DAX > bool "File system based Direct Access (DAX) support" > depends on MMU > - depends on !(ARM || MIPS || SPARC) > depends on ZONE_DEVICE || FS_DAX_LIMITED > select FS_IOMAP > select DAX > diff --git a/include/linux/dax.h b/include/linux/dax.h > index b463502b16e1..cfc8cd4a3eae 100644 > --- a/include/linux/dax.h > +++ b/include/linux/dax.h > @@ -78,6 +78,12 @@ static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, > return false; > return dax_synchronous(dax_dev); > } > +static inline bool dax_is_supported(void) > +{ > + return !IS_ENABLED(CONFIG_ARM) && > + !IS_ENABLED(CONFIG_MIPS) && > + !IS_ENABLED(CONFIG_SPARC); > +} Uh, ok. Now I see what dax_is_supported() does. I think this should be folded into fs_dax_get_by_bdev(), which currently returns NULL if CONFIG_FS_DAX=n and so should be cahnged to return NULL if any of these platform configs is enabled. Then I don't think you need to change a single line of filesystem code - they'll all just do what they do now if the block device doesn't support DAX.... -Dave.
diff --git a/fs/Kconfig b/fs/Kconfig index 42837617a55b..e5efdb3b276b 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -56,7 +56,6 @@ endif # BLOCK config FS_DAX bool "File system based Direct Access (DAX) support" depends on MMU - depends on !(ARM || MIPS || SPARC) depends on ZONE_DEVICE || FS_DAX_LIMITED select FS_IOMAP select DAX diff --git a/include/linux/dax.h b/include/linux/dax.h index b463502b16e1..cfc8cd4a3eae 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -78,6 +78,12 @@ static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, return false; return dax_synchronous(dax_dev); } +static inline bool dax_is_supported(void) +{ + return !IS_ENABLED(CONFIG_ARM) && + !IS_ENABLED(CONFIG_MIPS) && + !IS_ENABLED(CONFIG_SPARC); +} #else static inline void *dax_holder(struct dax_device *dax_dev) { @@ -122,6 +128,10 @@ static inline size_t dax_recovery_write(struct dax_device *dax_dev, { return 0; } +static inline bool dax_is_supported(void) +{ + return false; +} #endif void set_dax_nocache(struct dax_device *dax_dev);
Introduce a new dax_is_supported() static inline to check whether the architecture supports DAX. This replaces the following fs/Kconfig:FS_DAX dependency: depends on !(ARM || MIPS || SPARC) This is done in preparation for its use by each filesystem supporting the dax mount option to validate whether dax is indeed supported. This is done in preparation for using dcache_is_aliasing() in a following change which will properly support architectures which detect dcache aliasing at runtime. Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches") Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-mm@kvack.org Cc: linux-arch@vger.kernel.org Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@armlinux.org.uk> Cc: nvdimm@lists.linux.dev Cc: linux-cxl@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org --- fs/Kconfig | 1 - include/linux/dax.h | 10 ++++++++++ 2 files changed, 10 insertions(+), 1 deletion(-)