diff options
| -rw-r--r-- | arch/x86/pci/i386.c | 68 |
1 files changed, 60 insertions, 8 deletions
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c index 103b9dff121..4ebf52f6b1f 100644 --- a/arch/x86/pci/i386.c +++ b/arch/x86/pci/i386.c @@ -30,6 +30,9 @@ #include <linux/init.h> #include <linux/ioport.h> #include <linux/errno.h> +#include <linux/bootmem.h> + +#include <asm/pat.h> #include "pci.h" @@ -297,10 +300,34 @@ void pcibios_set_master(struct pci_dev *dev) pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat); } +static void pci_unmap_page_range(struct vm_area_struct *vma) +{ + u64 addr = (u64)vma->vm_pgoff << PAGE_SHIFT; + free_memtype(addr, addr + vma->vm_end - vma->vm_start); +} + +static void pci_track_mmap_page_range(struct vm_area_struct *vma) +{ + u64 addr = (u64)vma->vm_pgoff << PAGE_SHIFT; + unsigned long flags = pgprot_val(vma->vm_page_prot) + & _PAGE_CACHE_MASK; + + reserve_memtype(addr, addr + vma->vm_end - vma->vm_start, flags, NULL); +} + +static struct vm_operations_struct pci_mmap_ops = { + .open = pci_track_mmap_page_range, + .close = pci_unmap_page_range, +}; + int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, enum pci_mmap_state mmap_state, int write_combine) { unsigned long prot; + u64 addr = vma->vm_pgoff << PAGE_SHIFT; + unsigned long len = vma->vm_end - vma->vm_start; + unsigned long flags; + unsigned long new_flags; /* I/O space cannot be accessed via normal processor loads and * stores on this platform. @@ -308,21 +335,46 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, if (mmap_state == pci_mmap_io) return -EINVAL; - /* Leave vm_pgoff as-is, the PCI space address is the physical - * address on this platform. - */ prot = pgprot_val(vma->vm_page_prot); - if (boot_cpu_data.x86 > 3) - prot |= _PAGE_PCD | _PAGE_PWT; + if (pat_wc_enabled && write_combine) + prot |= _PAGE_CACHE_WC; + else if (boot_cpu_data.x86 > 3) + prot |= _PAGE_CACHE_UC; + vma->vm_page_prot = __pgprot(prot); - /* Write-combine setting is ignored, it is changed via the mtrr - * interfaces on this platform. - */ + flags = pgprot_val(vma->vm_page_prot) & _PAGE_CACHE_MASK; + if (reserve_memtype(addr, addr + len, flags, &new_flags)) { + /* + * Do not fallback to certain memory types with certain + * requested type: + * - request is uncached, return cannot be write-back + * - request is uncached, return cannot be write-combine + * - request is write-combine, return cannot be write-back + */ + if ((flags == _PAGE_CACHE_UC && + (new_flags == _PAGE_CACHE_WB || + new_flags == _PAGE_CACHE_WC)) || + (flags == _PAGE_CACHE_WC && + new_flags == _PAGE_CACHE_WB)) { + free_memtype(addr, addr+len); + return -EINVAL; + } + flags = new_flags; + } + + if (vma->vm_pgoff <= max_pfn_mapped && + ioremap_change_attr((unsigned long)__va(addr), len, flags)) { + free_memtype(addr, addr + len); + return -EINVAL; + } + if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, vma->vm_end - vma->vm_start, vma->vm_page_prot)) return -EAGAIN; + vma->vm_ops = &pci_mmap_ops; + return 0; } |