diff options
Diffstat (limited to 'mm/vmalloc.c')
| -rw-r--r-- | mm/vmalloc.c | 52 |
1 files changed, 32 insertions, 20 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 2aad49981b57..2bb90b1d241c 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -413,11 +413,11 @@ nocache: if (addr + size - 1 < addr) goto overflow; - n = rb_next(&first->rb_node); - if (n) - first = rb_entry(n, struct vmap_area, rb_node); - else + if (list_is_last(&first->list, &vmap_area_list)) goto found; + + first = list_entry(first->list.next, + struct vmap_area, list); } found: @@ -904,6 +904,14 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask) BUG_ON(size & ~PAGE_MASK); BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC); + if (WARN_ON(size == 0)) { + /* + * Allocating 0 bytes isn't what caller wants since + * get_order(0) returns funny result. Just warn and terminate + * early. + */ + return NULL; + } order = get_order(size); again: @@ -1280,7 +1288,7 @@ DEFINE_RWLOCK(vmlist_lock); struct vm_struct *vmlist; static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, - unsigned long flags, void *caller) + unsigned long flags, const void *caller) { vm->flags = flags; vm->addr = (void *)va->va_start; @@ -1306,7 +1314,7 @@ static void insert_vmalloc_vmlist(struct vm_struct *vm) } static void insert_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, - unsigned long flags, void *caller) + unsigned long flags, const void *caller) { setup_vmalloc_vm(vm, va, flags, caller); insert_vmalloc_vmlist(vm); @@ -1314,7 +1322,7 @@ static void insert_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, static struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long align, unsigned long flags, unsigned long start, - unsigned long end, int node, gfp_t gfp_mask, void *caller) + unsigned long end, int node, gfp_t gfp_mask, const void *caller) { struct vmap_area *va; struct vm_struct *area; @@ -1375,7 +1383,7 @@ EXPORT_SYMBOL_GPL(__get_vm_area); struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags, unsigned long start, unsigned long end, - void *caller) + const void *caller) { return __get_vm_area_node(size, 1, flags, start, end, -1, GFP_KERNEL, caller); @@ -1397,13 +1405,21 @@ struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) } struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags, - void *caller) + const void *caller) { return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END, -1, GFP_KERNEL, caller); } -static struct vm_struct *find_vm_area(const void *addr) +/** + * find_vm_area - find a continuous kernel virtual area + * @addr: base address + * + * Search for the kernel VM area starting at @addr, and return it. + * It is up to the caller to do all required locking to keep the returned + * pointer valid. + */ +struct vm_struct *find_vm_area(const void *addr) { struct vmap_area *va; @@ -1568,9 +1584,9 @@ EXPORT_SYMBOL(vmap); static void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask, pgprot_t prot, - int node, void *caller); + int node, const void *caller); static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, - pgprot_t prot, int node, void *caller) + pgprot_t prot, int node, const void *caller) { const int order = 0; struct page **pages; @@ -1643,7 +1659,7 @@ fail: */ void *__vmalloc_node_range(unsigned long size, unsigned long align, unsigned long start, unsigned long end, gfp_t gfp_mask, - pgprot_t prot, int node, void *caller) + pgprot_t prot, int node, const void *caller) { struct vm_struct *area; void *addr; @@ -1699,7 +1715,7 @@ fail: */ static void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask, pgprot_t prot, - int node, void *caller) + int node, const void *caller) { return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, gfp_mask, prot, node, caller); @@ -1975,9 +1991,7 @@ static int aligned_vwrite(char *buf, char *addr, unsigned long count) * IOREMAP area is treated as memory hole and no copy is done. * * If [addr...addr+count) doesn't includes any intersects with alive - * vm_struct area, returns 0. - * @buf should be kernel's buffer. Because this function uses KM_USER0, - * the caller should guarantee KM_USER0 is not used. + * vm_struct area, returns 0. @buf should be kernel's buffer. * * Note: In usual ops, vread() is never necessary because the caller * should know vmalloc() area is valid and can use memcpy(). @@ -2051,9 +2065,7 @@ finished: * IOREMAP area is treated as memory hole and no copy is done. * * If [addr...addr+count) doesn't includes any intersects with alive - * vm_struct area, returns 0. - * @buf should be kernel's buffer. Because this function uses KM_USER0, - * the caller should guarantee KM_USER0 is not used. + * vm_struct area, returns 0. @buf should be kernel's buffer. * * Note: In usual ops, vwrite() is never necessary because the caller * should know vmalloc() area is valid and can use memcpy(). |