From 1e70cdd6e654a66b4f6296a92cd0f7c265a02429 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 17 Jun 2016 14:43:33 -0500 Subject: powerpc/pci: Remove __pci_mmap_set_pgprot() The powerpc-specific __pci_mmap_set_pgprot() does two things: 1) Disables write combining for I/O port space mappings This only affects procfs mappings. The pci_mmap_resource() sysfs path only requests write combining for resources with IORESOURCE_PREFETCH set, which doesn't include I/O resources. The only way to request write combining for I/O port space mappings was via the PCIIOC_WRITE_COMBINE ioctl and the proc_bus_pci_mmap() path, and we recently changed that path to ignore write combining for I/O, so this code in powerpc is no longer needed. 2) Automatically enables write combining for mappings of prefetchable resources, even if not requested by the user Both procfs (via PCIIOC_MMAP_IS_MEM and PCIIOC_WRITE_COMBINE ioctls) and sysfs (via "resourceN_wc" files, which are created for resources with IORESOURCE_PREFETCH) provide ways for the user to map PCI memory space with write combining. Users that desire write combining should use one of those ways instead of relying on powerpc-specific behavior. Remove the powerpc-specific __pci_mmap_set_pgprot(). The user-visible effect of this change is that powerpc users mapping prefetchable PCI memory space via procfs without PCIIOC_WRITE_COMBINE or via sysfs "resourceN" (not "resourceN_wc") will get regular uncacheable mappings instead of the write combining mappings they used to get. The new behavior matches the behavior on all other arches that support write combining mapping. [bhelgaas: changelog] Signed-off-by: Yinghai Lu Signed-off-by: Bjorn Helgaas --- arch/powerpc/kernel/pci-common.c | 37 ++++--------------------------------- 1 file changed, 4 insertions(+), 33 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 0f7a60f1e9f6..8c6beb0229fe 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -355,36 +355,6 @@ static struct resource *__pci_mmap_make_offset(struct pci_dev *dev, return NULL; } -/* - * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci - * device mapping. - */ -static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp, - pgprot_t protection, - enum pci_mmap_state mmap_state, - int write_combine) -{ - - /* Write combine is always 0 on non-memory space mappings. On - * memory space, if the user didn't pass 1, we check for a - * "prefetchable" resource. This is a bit hackish, but we use - * this to workaround the inability of /sysfs to provide a write - * combine bit - */ - if (mmap_state != pci_mmap_mem) - write_combine = 0; - else if (write_combine == 0) { - if (rp->flags & IORESOURCE_PREFETCH) - write_combine = 1; - } - - /* XXX would be nice to have a way to ask for write-through */ - if (write_combine) - return pgprot_noncached_wc(protection); - else - return pgprot_noncached(protection); -} - /* * This one is used by /dev/mem and fbdev who have no clue about the * PCI device, it tries to find the PCI device first and calls the @@ -458,9 +428,10 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, return -EINVAL; vma->vm_pgoff = offset >> PAGE_SHIFT; - vma->vm_page_prot = __pci_mmap_set_pgprot(dev, rp, - vma->vm_page_prot, - mmap_state, write_combine); + if (write_combine) + vma->vm_page_prot = pgprot_noncached_wc(vma->vm_page_prot); + else + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); ret = remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, vma->vm_end - vma->vm_start, vma->vm_page_prot); -- cgit v1.2.3 From 8221a013528597edc18d371b22667e8eefca599b Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 17 Jun 2016 14:43:34 -0500 Subject: PCI: Unify pci_resource_to_user() declarations Replace the pci_resource_to_user() declarations in each arch that defines HAVE_ARCH_PCI_RESOURCE_TO_USER with a single one in linux/pci.h. Change the MIPS static inline implementation to a non-inline version so the static inline doesn't conflict with the new non-static linux/pci.h declaration. No functional change intended. Signed-off-by: Bjorn Helgaas --- arch/microblaze/include/asm/pci.h | 3 --- arch/mips/include/asm/pci.h | 10 ---------- arch/mips/pci/pci.c | 10 ++++++++++ arch/powerpc/include/asm/pci.h | 3 --- arch/sparc/include/asm/pci_64.h | 3 --- include/linux/pci.h | 6 +++++- 6 files changed, 15 insertions(+), 20 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/microblaze/include/asm/pci.h b/arch/microblaze/include/asm/pci.h index fc3ecb55f1b2..2a120bb70e54 100644 --- a/arch/microblaze/include/asm/pci.h +++ b/arch/microblaze/include/asm/pci.h @@ -82,9 +82,6 @@ extern pgprot_t pci_phys_mem_access_prot(struct file *file, pgprot_t prot); #define HAVE_ARCH_PCI_RESOURCE_TO_USER -extern void pci_resource_to_user(const struct pci_dev *dev, int bar, - const struct resource *rsrc, - resource_size_t *start, resource_size_t *end); extern void pcibios_setup_bus_devices(struct pci_bus *bus); extern void pcibios_setup_bus_self(struct pci_bus *bus); diff --git a/arch/mips/include/asm/pci.h b/arch/mips/include/asm/pci.h index 86b239d9d75d..9b63cd41213d 100644 --- a/arch/mips/include/asm/pci.h +++ b/arch/mips/include/asm/pci.h @@ -80,16 +80,6 @@ extern int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, #define HAVE_ARCH_PCI_RESOURCE_TO_USER -static inline void pci_resource_to_user(const struct pci_dev *dev, int bar, - const struct resource *rsrc, resource_size_t *start, - resource_size_t *end) -{ - phys_addr_t size = resource_size(rsrc); - - *start = fixup_bigphys_addr(rsrc->start, size); - *end = rsrc->start + size; -} - /* * Dynamic DMA mapping stuff. * MIPS has everything mapped statically. diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c index f1b11f0dea2d..5717384a986d 100644 --- a/arch/mips/pci/pci.c +++ b/arch/mips/pci/pci.c @@ -319,6 +319,16 @@ void pcibios_fixup_bus(struct pci_bus *bus) EXPORT_SYMBOL(PCIBIOS_MIN_IO); EXPORT_SYMBOL(PCIBIOS_MIN_MEM); +void pci_resource_to_user(const struct pci_dev *dev, int bar, + const struct resource *rsrc, resource_size_t *start, + resource_size_t *end) +{ + phys_addr_t size = resource_size(rsrc); + + *start = fixup_bigphys_addr(rsrc->start, size); + *end = rsrc->start + size; +} + int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, enum pci_mmap_state mmap_state, int write_combine) { diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h index a6f3ac0d4602..e9bd6cf0212f 100644 --- a/arch/powerpc/include/asm/pci.h +++ b/arch/powerpc/include/asm/pci.h @@ -136,9 +136,6 @@ extern pgprot_t pci_phys_mem_access_prot(struct file *file, pgprot_t prot); #define HAVE_ARCH_PCI_RESOURCE_TO_USER -extern void pci_resource_to_user(const struct pci_dev *dev, int bar, - const struct resource *rsrc, - resource_size_t *start, resource_size_t *end); extern resource_size_t pcibios_io_space_offset(struct pci_controller *hose); extern void pcibios_setup_bus_devices(struct pci_bus *bus); diff --git a/arch/sparc/include/asm/pci_64.h b/arch/sparc/include/asm/pci_64.h index 022d16008a00..2303635158f5 100644 --- a/arch/sparc/include/asm/pci_64.h +++ b/arch/sparc/include/asm/pci_64.h @@ -55,9 +55,6 @@ static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel) } #define HAVE_ARCH_PCI_RESOURCE_TO_USER -void pci_resource_to_user(const struct pci_dev *dev, int bar, - const struct resource *rsrc, - resource_size_t *start, resource_size_t *end); #endif /* __KERNEL__ */ #endif /* __SPARC64_PCI_H */ diff --git a/include/linux/pci.h b/include/linux/pci.h index b67e4df20801..9c201d4dbd51 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1554,7 +1554,11 @@ static inline const char *pci_name(const struct pci_dev *pdev) /* Some archs don't want to expose struct resource to userland as-is * in sysfs and /proc */ -#ifndef HAVE_ARCH_PCI_RESOURCE_TO_USER +#ifdef HAVE_ARCH_PCI_RESOURCE_TO_USER +void pci_resource_to_user(const struct pci_dev *dev, int bar, + const struct resource *rsrc, + resource_size_t *start, resource_size_t *end); +#else static inline void pci_resource_to_user(const struct pci_dev *dev, int bar, const struct resource *rsrc, resource_size_t *start, resource_size_t *end) -- cgit v1.2.3 From 38301358573be7398e43115170f2d76598c8d43b Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 17 Jun 2016 14:43:34 -0500 Subject: powerpc/pci: Implement pci_resource_to_user() with pcibios_resource_to_bus() "User" addresses are shown in /sys/devices/pci.../.../resource and /proc/bus/pci/devices and used as mmap offsets for /proc/bus/pci/BB/DD.F files. For I/O port resources on powerpc, these are PCI bus addresses, i.e., raw BAR values. Previously pci_resource_to_user() computed the user address by subtracting "hose->io_base_virt - _IO_BASE" from the resource start: pci_resource_to_user() if (IO) offset = (unsigned long)hose->io_base_virt - _IO_BASE; *start = rsrc->start - offset; We've already told the PCI core about that "hose->io_base_virt - _IO_BASE" offset: pcibios_setup_phb_resources() res = &hose->io_resource; offset = pcibios_io_space_offset(); /* i.e., "offset = hose->io_base_virt - _IO_BASE" */ pci_add_resource_offset(resources, res, offset); so pcibios_resource_to_bus() knows how to do that translation. No functional change intended. Signed-off-by: Bjorn Helgaas Acked-by: Yinghai Lu --- arch/powerpc/kernel/pci-common.c | 42 ++++++++++++++-------------------------- 1 file changed, 14 insertions(+), 28 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 8c6beb0229fe..6de6e0e96ce5 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -581,39 +581,25 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar, const struct resource *rsrc, resource_size_t *start, resource_size_t *end) { - struct pci_controller *hose = pci_bus_to_host(dev->bus); - resource_size_t offset = 0; + struct pci_bus_region region; - if (hose == NULL) + if (rsrc->flags & IORESOURCE_IO) { + pcibios_resource_to_bus(dev->bus, ®ion, + (struct resource *) rsrc); + *start = region.start; + *end = region.end; return; + } - if (rsrc->flags & IORESOURCE_IO) - offset = (unsigned long)hose->io_base_virt - _IO_BASE; - - /* We pass a fully fixed up address to userland for MMIO instead of - * a BAR value because X is lame and expects to be able to use that - * to pass to /dev/mem ! - * - * That means that we'll have potentially 64 bits values where some - * userland apps only expect 32 (like X itself since it thinks only - * Sparc has 64 bits MMIO) but if we don't do that, we break it on - * 32 bits CHRPs :-( - * - * Hopefully, the sysfs insterface is immune to that gunk. Once X - * has been fixed (and the fix spread enough), we can re-enable the - * 2 lines below and pass down a BAR value to userland. In that case - * we'll also have to re-enable the matching code in - * __pci_mmap_make_offset(). + /* We pass a CPU physical address to userland for MMIO instead of a + * BAR value because X is lame and expects to be able to use that + * to pass to /dev/mem! * - * BenH. + * That means we may have 64-bit values where some apps only expect + * 32 (like X itself since it thinks only Sparc has 64-bit MMIO). */ -#if 0 - else if (rsrc->flags & IORESOURCE_MEM) - offset = hose->pci_mem_offset; -#endif - - *start = rsrc->start - offset; - *end = rsrc->end - offset; + *start = rsrc->start; + *end = rsrc->end; } /** -- cgit v1.2.3