| Message ID | 20230515090848.833045-11-bhe@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: ioremap: Convert architectures to take GENERIC_IOREMAP way | expand |
On Mon, May 15, 2023 at 05:08:41PM +0800, Baoquan He wrote: > By taking GENERIC_IOREMAP method, the generic generic_ioremap_prot(), > generic_iounmap(), and their generic wrapper ioremap_prot(), ioremap() > and iounmap() are all visible and available to arch. Arch needs to > provide wrapper functions to override the generic versions if there's > arch specific handling in its ioremap_prot(), ioremap() or iounmap(). > This change will simplify implementation by removing duplicated codes > with generic_ioremap_prot() and generic_iounmap(), and has the equivalent > functioality as before. > > Here, add wrapper functions ioremap_prot() and iounmap() for s390's > special operation when ioremap() and iounmap(). > > Signed-off-by: Baoquan He <bhe@redhat.com> > Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> > Tested-by: Niklas Schnelle <schnelle@linux.ibm.com> > Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> > Cc: Heiko Carstens <hca@linux.ibm.com> > Cc: Vasily Gorbik <gor@linux.ibm.com> > Cc: Alexander Gordeev <agordeev@linux.ibm.com> > Cc: Christian Borntraeger <borntraeger@linux.ibm.com> > Cc: Sven Schnelle <svens@linux.ibm.com> > Cc: linux-s390@vger.kernel.org Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org> > --- > arch/s390/Kconfig | 1 + > arch/s390/include/asm/io.h | 21 ++++++++------ > arch/s390/pci/pci.c | 57 +++++++------------------------------- > 3 files changed, 23 insertions(+), 56 deletions(-) > > diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig > index db20c1589a98..f33923fa8c99 100644 > --- a/arch/s390/Kconfig > +++ b/arch/s390/Kconfig > @@ -142,6 +142,7 @@ config S390 > select GENERIC_SMP_IDLE_THREAD > select GENERIC_TIME_VSYSCALL > select GENERIC_VDSO_TIME_NS > + select GENERIC_IOREMAP if PCI > select HAVE_ALIGNED_STRUCT_PAGE if SLUB > select HAVE_ARCH_AUDITSYSCALL > select HAVE_ARCH_JUMP_LABEL > diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h > index e3882b012bfa..4453ad7c11ac 100644 > --- a/arch/s390/include/asm/io.h > +++ b/arch/s390/include/asm/io.h > @@ -22,11 +22,18 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr); > > #define IO_SPACE_LIMIT 0 > > -void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot); > -void __iomem *ioremap(phys_addr_t addr, size_t size); > -void __iomem *ioremap_wc(phys_addr_t addr, size_t size); > -void __iomem *ioremap_wt(phys_addr_t addr, size_t size); > -void iounmap(volatile void __iomem *addr); > +/* > + * I/O memory mapping functions. > + */ > +#define ioremap_prot ioremap_prot > +#define iounmap iounmap > + > +#define _PAGE_IOREMAP pgprot_val(PAGE_KERNEL) > + > +#define ioremap_wc(addr, size) \ > + ioremap_prot((addr), (size), pgprot_val(pgprot_writecombine(PAGE_KERNEL))) > +#define ioremap_wt(addr, size) \ > + ioremap_prot((addr), (size), pgprot_val(pgprot_writethrough(PAGE_KERNEL))) > > static inline void __iomem *ioport_map(unsigned long port, unsigned int nr) > { > @@ -51,10 +58,6 @@ static inline void ioport_unmap(void __iomem *p) > #define pci_iomap_wc pci_iomap_wc > #define pci_iomap_wc_range pci_iomap_wc_range > > -#define ioremap ioremap > -#define ioremap_wt ioremap_wt > -#define ioremap_wc ioremap_wc > - > #define memcpy_fromio(dst, src, count) zpci_memcpy_fromio(dst, src, count) > #define memcpy_toio(dst, src, count) zpci_memcpy_toio(dst, src, count) > #define memset_io(dst, val, count) zpci_memset_io(dst, val, count) > diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c > index afc3f33788da..d34d5813d006 100644 > --- a/arch/s390/pci/pci.c > +++ b/arch/s390/pci/pci.c > @@ -244,62 +244,25 @@ void __iowrite64_copy(void __iomem *to, const void *from, size_t count) > zpci_memcpy_toio(to, from, count); > } > > -static void __iomem *__ioremap(phys_addr_t addr, size_t size, pgprot_t prot) > +void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size, > + unsigned long prot) > { > - unsigned long offset, vaddr; > - struct vm_struct *area; > - phys_addr_t last_addr; > - > - last_addr = addr + size - 1; > - if (!size || last_addr < addr) > - return NULL; > - > + /* > + * When PCI MIO instructions are unavailable the "physical" address > + * encodes a hint for accessing the PCI memory space it represents. > + * Just pass it unchanged such that ioread/iowrite can decode it. > + */ > if (!static_branch_unlikely(&have_mio)) > - return (void __iomem *) addr; > + return (void __iomem *)phys_addr; > > - offset = addr & ~PAGE_MASK; > - addr &= PAGE_MASK; > - size = PAGE_ALIGN(size + offset); > - area = get_vm_area(size, VM_IOREMAP); > - if (!area) > - return NULL; > - > - vaddr = (unsigned long) area->addr; > - if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) { > - free_vm_area(area); > - return NULL; > - } > - return (void __iomem *) ((unsigned long) area->addr + offset); > -} > - > -void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot) > -{ > - return __ioremap(addr, size, __pgprot(prot)); > + return generic_ioremap_prot(phys_addr, size, __pgprot(prot)); > } > EXPORT_SYMBOL(ioremap_prot); > > -void __iomem *ioremap(phys_addr_t addr, size_t size) > -{ > - return __ioremap(addr, size, PAGE_KERNEL); > -} > -EXPORT_SYMBOL(ioremap); > - > -void __iomem *ioremap_wc(phys_addr_t addr, size_t size) > -{ > - return __ioremap(addr, size, pgprot_writecombine(PAGE_KERNEL)); > -} > -EXPORT_SYMBOL(ioremap_wc); > - > -void __iomem *ioremap_wt(phys_addr_t addr, size_t size) > -{ > - return __ioremap(addr, size, pgprot_writethrough(PAGE_KERNEL)); > -} > -EXPORT_SYMBOL(ioremap_wt); > - > void iounmap(volatile void __iomem *addr) > { > if (static_branch_likely(&have_mio)) > - vunmap((__force void *) ((unsigned long) addr & PAGE_MASK)); > + generic_iounmap(addr); > } > EXPORT_SYMBOL(iounmap); > > -- > 2.34.1 > >
On Mon, May 15, 2023 at 05:08:41PM +0800, Baoquan He wrote: > +#define ioremap_wc(addr, size) \ > + ioremap_prot((addr), (size), pgprot_val(pgprot_writecombine(PAGE_KERNEL))) I'd move this out of line and just apply mio_wb_bit_mask directly instead of the unbox/box/unbox/box dance. > +#define ioremap_wt(addr, size) \ > + ioremap_prot((addr), (size), pgprot_val(pgprot_writethrough(PAGE_KERNEL))) and just define this to ioremap_wc. Note that defining _wt to _wc is very odd and seems wrong, but comes from the existing code. Maybe the s390 maintainers can chime on on the background and we can add a comment while we're at it. Otherwise looks good: Reviewed-by: Christoph Hellwig <hch@lst.de>
On Tue, 2023-05-16 at 23:36 -0700, Christoph Hellwig wrote: > On Mon, May 15, 2023 at 05:08:41PM +0800, Baoquan He wrote: > > +#define ioremap_wc(addr, size) \ > > + ioremap_prot((addr), (size), pgprot_val(pgprot_writecombine(PAGE_KERNEL))) > > I'd move this out of line and just apply mio_wb_bit_mask directly > instead of the unbox/box/unbox/box dance. > > > +#define ioremap_wt(addr, size) \ > > + ioremap_prot((addr), (size), pgprot_val(pgprot_writethrough(PAGE_KERNEL))) > > and just define this to ioremap_wc. Note that defining _wt to _wc is > very odd and seems wrong, but comes from the existing code. Maybe the > s390 maintainers can chime on on the background and we can add a comment > while we're at it. I'm a bit confused where you see ioremap_wt() defined to ioremap_wc() in the existing code? Our current definitions are: void __iomem *ioremap_wc(phys_addr_t addr, size_t size) { return __ioremap(addr, size, pgprot_writecombine(PAGE_KERNEL)); } void __iomem *ioremap_wt(phys_addr_t addr, size_t size) { return __ioremap(addr, size, pgprot_writethrough(PAGE_KERNEL)); } Now if we don't have support for the enhanced PCI load/store instructions (memory I/O aka MIO) then yes this gets ignored and both .._wc() and .._wt() act the same but if we do have them pgprot_writecombine() / pgprot_writethrough() set respectively clear the mio_wb bit in the PTE. It's a bit odd here because the exact position of the bit is read from a firmware interface and could in theory change but other than that it looks fine to me and yes I agree that it would be odd and broken to define _wt to _wc. Thanks, Niklas
On Wed, May 17, 2023 at 09:58:26AM +0200, Niklas Schnelle wrote: > > and just define this to ioremap_wc. Note that defining _wt to _wc is > > very odd and seems wrong, but comes from the existing code. Maybe the > > s390 maintainers can chime on on the background and we can add a comment > > while we're at it. > > I'm a bit confused where you see ioremap_wt() defined to ioremap_wc() > in the existing code? Our current definitions are: No, it's me wo is confused. They clearly are different. But the same comment about just moving ioremap_wc applies to ioremap_wt based on how pgprot_writethrough is implemented then.
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index db20c1589a98..f33923fa8c99 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -142,6 +142,7 @@ config S390 select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL select GENERIC_VDSO_TIME_NS + select GENERIC_IOREMAP if PCI select HAVE_ALIGNED_STRUCT_PAGE if SLUB select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_JUMP_LABEL diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h index e3882b012bfa..4453ad7c11ac 100644 --- a/arch/s390/include/asm/io.h +++ b/arch/s390/include/asm/io.h @@ -22,11 +22,18 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr); #define IO_SPACE_LIMIT 0 -void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot); -void __iomem *ioremap(phys_addr_t addr, size_t size); -void __iomem *ioremap_wc(phys_addr_t addr, size_t size); -void __iomem *ioremap_wt(phys_addr_t addr, size_t size); -void iounmap(volatile void __iomem *addr); +/* + * I/O memory mapping functions. + */ +#define ioremap_prot ioremap_prot +#define iounmap iounmap + +#define _PAGE_IOREMAP pgprot_val(PAGE_KERNEL) + +#define ioremap_wc(addr, size) \ + ioremap_prot((addr), (size), pgprot_val(pgprot_writecombine(PAGE_KERNEL))) +#define ioremap_wt(addr, size) \ + ioremap_prot((addr), (size), pgprot_val(pgprot_writethrough(PAGE_KERNEL))) static inline void __iomem *ioport_map(unsigned long port, unsigned int nr) { @@ -51,10 +58,6 @@ static inline void ioport_unmap(void __iomem *p) #define pci_iomap_wc pci_iomap_wc #define pci_iomap_wc_range pci_iomap_wc_range -#define ioremap ioremap -#define ioremap_wt ioremap_wt -#define ioremap_wc ioremap_wc - #define memcpy_fromio(dst, src, count) zpci_memcpy_fromio(dst, src, count) #define memcpy_toio(dst, src, count) zpci_memcpy_toio(dst, src, count) #define memset_io(dst, val, count) zpci_memset_io(dst, val, count) diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c index afc3f33788da..d34d5813d006 100644 --- a/arch/s390/pci/pci.c +++ b/arch/s390/pci/pci.c @@ -244,62 +244,25 @@ void __iowrite64_copy(void __iomem *to, const void *from, size_t count) zpci_memcpy_toio(to, from, count); } -static void __iomem *__ioremap(phys_addr_t addr, size_t size, pgprot_t prot) +void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size, + unsigned long prot) { - unsigned long offset, vaddr; - struct vm_struct *area; - phys_addr_t last_addr; - - last_addr = addr + size - 1; - if (!size || last_addr < addr) - return NULL; - + /* + * When PCI MIO instructions are unavailable the "physical" address + * encodes a hint for accessing the PCI memory space it represents. + * Just pass it unchanged such that ioread/iowrite can decode it. + */ if (!static_branch_unlikely(&have_mio)) - return (void __iomem *) addr; + return (void __iomem *)phys_addr; - offset = addr & ~PAGE_MASK; - addr &= PAGE_MASK; - size = PAGE_ALIGN(size + offset); - area = get_vm_area(size, VM_IOREMAP); - if (!area) - return NULL; - - vaddr = (unsigned long) area->addr; - if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) { - free_vm_area(area); - return NULL; - } - return (void __iomem *) ((unsigned long) area->addr + offset); -} - -void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot) -{ - return __ioremap(addr, size, __pgprot(prot)); + return generic_ioremap_prot(phys_addr, size, __pgprot(prot)); } EXPORT_SYMBOL(ioremap_prot); -void __iomem *ioremap(phys_addr_t addr, size_t size) -{ - return __ioremap(addr, size, PAGE_KERNEL); -} -EXPORT_SYMBOL(ioremap); - -void __iomem *ioremap_wc(phys_addr_t addr, size_t size) -{ - return __ioremap(addr, size, pgprot_writecombine(PAGE_KERNEL)); -} -EXPORT_SYMBOL(ioremap_wc); - -void __iomem *ioremap_wt(phys_addr_t addr, size_t size) -{ - return __ioremap(addr, size, pgprot_writethrough(PAGE_KERNEL)); -} -EXPORT_SYMBOL(ioremap_wt); - void iounmap(volatile void __iomem *addr) { if (static_branch_likely(&have_mio)) - vunmap((__force void *) ((unsigned long) addr & PAGE_MASK)); + generic_iounmap(addr); } EXPORT_SYMBOL(iounmap);