diff options
| -rw-r--r-- | vm/vm_kern.c | 39 | ||||
| -rw-r--r-- | vm/vm_kern.h | 2 |
2 files changed, 41 insertions, 0 deletions
diff --git a/vm/vm_kern.c b/vm/vm_kern.c index 2e333ee1..8ecd2ed9 100644 --- a/vm/vm_kern.c +++ b/vm/vm_kern.c @@ -636,6 +636,45 @@ retry: } /* + * kmem_map_aligned_table: map a table or structure in a virtual memory page + * Align the table initial address with the page initial address. + * + * Parameters: + * phys_address: physical address, the start address of the table. + * size: size of the table. + * mode: access mode. VM_PROT_READ for read, VM_PROT_WRITE for write. + * + * Returns a reference to the virtual address if success, NULL if failure. + */ + +void* +kmem_map_aligned_table( + phys_addr_t phys_address, + vm_size_t size, + int mode) +{ + vm_offset_t virt_addr; + kern_return_t ret; + phys_addr_t into_page = phys_address % PAGE_SIZE; + phys_addr_t nearest_page = phys_address - into_page; + + size += into_page; + + ret = kmem_alloc_wired(kernel_map, &virt_addr, + round_page(size)); + + if (ret != KERN_SUCCESS) + return NULL; + + (void) pmap_map_bd(virt_addr, nearest_page, + nearest_page + round_page(size), mode); + + /* XXX remember mapping somewhere so we can free it? */ + + return (void *) (virt_addr + into_page); +} + +/* * kmem_alloc_pageable: * * Allocate pageable memory in the kernel's address map. diff --git a/vm/vm_kern.h b/vm/vm_kern.h index 0cdb19db..13115ff9 100644 --- a/vm/vm_kern.h +++ b/vm/vm_kern.h @@ -55,6 +55,8 @@ extern kern_return_t kmem_alloc_pageable(vm_map_t, vm_offset_t *, extern kern_return_t kmem_valloc(vm_map_t, vm_offset_t *, vm_size_t); extern kern_return_t kmem_alloc_wired(vm_map_t, vm_offset_t *, vm_size_t); extern kern_return_t kmem_alloc_aligned(vm_map_t, vm_offset_t *, vm_size_t); +extern void* kmem_map_aligned_table(phys_addr_t, vm_size_t, int); + extern void kmem_free(vm_map_t, vm_offset_t, vm_size_t); extern void kmem_submap(vm_map_t, vm_map_t, vm_offset_t *, |