diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/vmalloc.c | 975 |
1 files changed, 842 insertions, 133 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index bba06c41fc5..712ae47af0b 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -8,6 +8,7 @@ * Numa awareness, Christoph Lameter, SGI, June 2005 */ +#include <linux/vmalloc.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/highmem.h> @@ -18,16 +19,17 @@ #include <linux/debugobjects.h> #include <linux/vmalloc.h> #include <linux/kallsyms.h> +#include <linux/list.h> +#include <linux/rbtree.h> +#include <linux/radix-tree.h> +#include <linux/rcupdate.h> +#include <asm/atomic.h> #include <asm/uaccess.h> #include <asm/tlbflush.h> -DEFINE_RWLOCK(vmlist_lock); -struct vm_struct *vmlist; - -static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, - int node, void *caller); +/*** Page table manipulation functions ***/ static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) { @@ -40,8 +42,7 @@ static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) } while (pte++, addr += PAGE_SIZE, addr != end); } -static inline void vunmap_pmd_range(pud_t *pud, unsigned long addr, - unsigned long end) +static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end) { pmd_t *pmd; unsigned long next; @@ -55,8 +56,7 @@ static inline void vunmap_pmd_range(pud_t *pud, unsigned long addr, } while (pmd++, addr = next, addr != end); } -static inline void vunmap_pud_range(pgd_t *pgd, unsigned long addr, - unsigned long end) +static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end) { pud_t *pud; unsigned long next; @@ -70,12 +70,10 @@ static inline void vunmap_pud_range(pgd_t *pgd, unsigned long addr, } while (pud++, addr = next, addr != end); } -void unmap_kernel_range(unsigned long addr, unsigned long size) +static void vunmap_page_range(unsigned long addr, unsigned long end) { pgd_t *pgd; unsigned long next; - unsigned long start = addr; - unsigned long end = addr + size; BUG_ON(addr >= end); pgd = pgd_offset_k(addr); @@ -86,35 +84,36 @@ void unmap_kernel_range(unsigned long addr, unsigned long size) continue; vunmap_pud_range(pgd, addr, next); } while (pgd++, addr = next, addr != end); - flush_tlb_kernel_range(start, end); -} - -static void unmap_vm_area(struct vm_struct *area) -{ - unmap_kernel_range((unsigned long)area->addr, area->size); } static int vmap_pte_range(pmd_t *pmd, unsigned long addr, - unsigned long end, pgprot_t prot, struct page ***pages) + unsigned long end, pgprot_t prot, struct page **pages, int *nr) { pte_t *pte; + /* + * nr is a running index into the array which helps higher level + * callers keep track of where we're up to. + */ + pte = pte_alloc_kernel(pmd, addr); if (!pte) return -ENOMEM; do { - struct page *page = **pages; - WARN_ON(!pte_none(*pte)); - if (!page) + struct page *page = pages[*nr]; + + if (WARN_ON(!pte_none(*pte))) + return -EBUSY; + if (WARN_ON(!page)) return -ENOMEM; set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); - (*pages)++; + (*nr)++; } while (pte++, addr += PAGE_SIZE, addr != end); return 0; } -static inline int vmap_pmd_range(pud_t *pud, unsigned long addr, - unsigned long end, pgprot_t prot, struct page ***pages) +static int vmap_pmd_range(pud_t *pud, unsigned long addr, + unsigned long end, pgprot_t prot, struct page **pages, int *nr) { pmd_t *pmd; unsigned long next; @@ -124,14 +123,14 @@ static inline int vmap_pmd_range(pud_t *pud, unsigned long addr, return -ENOMEM; do { next = pmd_addr_end(addr, end); - if (vmap_pte_range(pmd, addr, next, prot, pages)) + if (vmap_pte_range(pmd, addr, next, prot, pages, nr)) return -ENOMEM; } while (pmd++, addr = next, addr != end); return 0; } -static inline int vmap_pud_range(pgd_t *pgd, unsigned long addr, - unsigned long end, pgprot_t prot, struct page ***pages) +static int vmap_pud_range(pgd_t *pgd, unsigned long addr, + unsigned long end, pgprot_t prot, struct page **pages, int *nr) { pud_t *pud; unsigned long next; @@ -141,44 +140,49 @@ static inline int vmap_pud_range(pgd_t *pgd, unsigned long addr, return -ENOMEM; do { next = pud_addr_end(addr, end); - if (vmap_pmd_range(pud, addr, next, prot, pages)) + if (vmap_pmd_range(pud, addr, next, prot, pages, nr)) return -ENOMEM; } while (pud++, addr = next, addr != end); return 0; } -int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages) +/* + * Set up page tables in kva (addr, end). The ptes shall have prot "prot", and + * will have pfns corresponding to the "pages" array. + * + * Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N] + */ +static int vmap_page_range(unsigned long addr, unsigned long end, + pgprot_t prot, struct page **pages) { pgd_t *pgd; unsigned long next; - unsigned long addr = (unsigned long) area->addr; - unsigned long end = addr + area->size - PAGE_SIZE; - int err; + int err = 0; + int nr = 0; BUG_ON(addr >= end); pgd = pgd_offset_k(addr); do { next = pgd_addr_end(addr, end); - err = vmap_pud_range(pgd, addr, next, prot, pages); + err = vmap_pud_range(pgd, addr, next, prot, pages, &nr); if (err) break; } while (pgd++, addr = next, addr != end); - flush_cache_vmap((unsigned long) area->addr, end); - return err; + flush_cache_vmap(addr, end); + + if (unlikely(err)) + return err; + return nr; } -EXPORT_SYMBOL_GPL(map_vm_area); /* - * Map a vmalloc()-space virtual address to the physical page. + * Walk a vmap address to the struct page it maps. */ struct page *vmalloc_to_page(const void *vmalloc_addr) { unsigned long addr = (unsigned long) vmalloc_addr; struct page *page = NULL; pgd_t *pgd = pgd_offset_k(addr); - pud_t *pud; - pmd_t *pmd; - pte_t *ptep, pte; /* * XXX we might need to change this if we add VIRTUAL_BUG_ON for @@ -188,10 +192,12 @@ struct page *vmalloc_to_page(const void *vmalloc_addr) !is_module_address(addr)); if (!pgd_none(*pgd)) { - pud = pud_offset(pgd, addr); + pud_t *pud = pud_offset(pgd, addr); if (!pud_none(*pud)) { - pmd = pmd_offset(pud, addr); + pmd_t *pmd = pmd_offset(pud, addr); if (!pmd_none(*pmd)) { + pte_t *ptep, pte; + ptep = pte_offset_map(pmd, addr); pte = *ptep; if (pte_present(pte)) @@ -213,13 +219,751 @@ unsigned long vmalloc_to_pfn(const void *vmalloc_addr) } EXPORT_SYMBOL(vmalloc_to_pfn); -static struct vm_struct * -__get_vm_area_node(unsigned long size, unsigned long flags, unsigned long start, - unsigned long end, int node, gfp_t gfp_mask, void *caller) + +/*** Global kva allocator ***/ + +#define VM_LAZY_FREE 0x01 +#define VM_LAZY_FREEING 0x02 +#define VM_VM_AREA 0x04 + +struct vmap_area { + unsigned long va_start; + unsigned long va_end; + unsigned long flags; + struct rb_node rb_node; /* address sorted rbtree */ + struct list_head list; /* address sorted list */ + struct list_head purge_list; /* "lazy purge" list */ + void *private; + struct rcu_head rcu_head; +}; + +static DEFINE_SPINLOCK(vmap_area_lock); +static struct rb_root vmap_area_root = RB_ROOT; +static LIST_HEAD(vmap_area_list); + +static struct vmap_area *__find_vmap_area(unsigned long addr) { - struct vm_struct **p, *tmp, *area; - unsigned long align = 1; + struct rb_node *n = vmap_area_root.rb_node; + + while (n) { + struct vmap_area *va; + + va = rb_entry(n, struct vmap_area, rb_node); + if (addr < va->va_start) + n = n->rb_left; + else if (addr > va->va_start) + n = n->rb_right; + else + return va; + } + + return NULL; +} + +static void __insert_vmap_area(struct vmap_area *va) +{ + struct rb_node **p = &vmap_area_root.rb_node; + struct rb_node *parent = NULL; + struct rb_node *tmp; + + while (*p) { + struct vmap_area *tmp; + + parent = *p; + tmp = rb_entry(parent, struct vmap_area, rb_node); + if (va->va_start < tmp->va_end) + p = &(*p)->rb_left; + else if (va->va_end > tmp->va_start) + p = &(*p)->rb_right; + else + BUG(); + } + + rb_link_node(&va->rb_node, parent, p); + rb_insert_color(&va->rb_node, &vmap_area_root); + + /* address-sort this list so it is usable like the vmlist */ + tmp = rb_prev(&va->rb_node); + if (tmp) { + struct vmap_area *prev; + prev = rb_entry(tmp, struct vmap_area, rb_node); + list_add_rcu(&va->list, &prev->list); + } else + list_add_rcu(&va->list, &vmap_area_list); +} + +static void purge_vmap_area_lazy(void); + +/* + * Allocate a region of KVA of the specified size and alignment, within the + * vstart and vend. + */ +static struct vmap_area *alloc_vmap_area(unsigned long size, + unsigned long align, + unsigned long vstart, unsigned long vend, + int node, gfp_t gfp_mask) +{ + struct vmap_area *va; + struct rb_node *n; + unsigned long addr; + int purged = 0; + + BUG_ON(size & ~PAGE_MASK); + + addr = ALIGN(vstart, align); + + va = kmalloc_node(sizeof(struct vmap_area), + gfp_mask & GFP_RECLAIM_MASK, node); + if (unlikely(!va)) + return ERR_PTR(-ENOMEM); + +retry: + spin_lock(&vmap_area_lock); + /* XXX: could have a last_hole cache */ + n = vmap_area_root.rb_node; + if (n) { + struct vmap_area *first = NULL; + + do { + struct vmap_area *tmp; + tmp = rb_entry(n, struct vmap_area, rb_node); + if (tmp->va_end >= addr) { + if (!first && tmp->va_start < addr + size) + first = tmp; + n = n->rb_left; + } else { + first = tmp; + n = n->rb_right; + } + } while (n); + + if (!first) + goto found; + + if (first->va_end < addr) { + n = rb_next(&first->rb_node); + if (n) + first = rb_entry(n, struct vmap_area, rb_node); + else + goto found; + } + + while (addr + size >= first->va_start && addr + size <= vend) { + addr = ALIGN(first->va_end + PAGE_SIZE, align); + + n = rb_next(&first->rb_node); + if (n) + first = rb_entry(n, struct vmap_area, rb_node); + else + goto found; + } + } +found: + if (addr + size > vend) { + spin_unlock(&vmap_area_lock); + if (!purged) { + purge_vmap_area_lazy(); + purged = 1; + goto retry; + } + if (printk_ratelimit()) + printk(KERN_WARNING "vmap allocation failed: " + "use vmalloc=<size> to increase size.\n"); + return ERR_PTR(-EBUSY); + } + + BUG_ON(addr & (align-1)); + + va->va_start = addr; + va->va_end = addr + size; + va->flags = 0; + __insert_vmap_area(va); + spin_unlock(&vmap_area_lock); + + return va; +} + +static void rcu_free_va(struct rcu_head *head) +{ + struct vmap_area *va = container_of(head, struct vmap_area, rcu_head); + + kfree(va); +} + +static void __free_vmap_area(struct vmap_area *va) +{ + BUG_ON(RB_EMPTY_NODE(&va->rb_node)); + rb_erase(&va->rb_node, &vmap_area_root); + RB_CLEAR_NODE(&va->rb_node); + list_del_rcu(&va->list); + + call_rcu(&va->rcu_head, rcu_free_va); +} + +/* + * Free a region of KVA allocated by alloc_vmap_area + */ +static void free_vmap_area(struct vmap_area *va) +{ + spin_lock(&vmap_area_lock); + __free_vmap_area(va); + spin_unlock(&vmap_area_lock); +} + +/* + * Clear the pagetable entries of a given vmap_area + */ +static void unmap_vmap_area(struct vmap_area *va) +{ + vunmap_page_range(va->va_start, va->va_end); +} + +/* + * lazy_max_pages is the maximum amount of virtual address space we gather up + * before attempting to purge with a TLB flush. + * + * There is a tradeoff here: a larger number will cover more kernel page tables + * and take slightly longer to purge, but it will linearly reduce the number of + * global TLB flushes that must be performed. It would seem natural to scale + * this number up linearly with the number of CPUs (because vmapping activity + * could also scale linearly with the number of CPUs), however it is likely + * that in practice, workloads might be constrained in other ways that mean + * vmap activity will not scale linearly with CPUs. Also, I want to be + * conservative and not introduce a big latency on huge systems, so go with + * a less aggressive log scale. It will still be an improvement over the old + * code, and it will be simple to change the scale factor if we find that it + * becomes a problem on bigger systems. + */ +static unsigned long lazy_max_pages(void) +{ + unsigned int log; + + log = fls(num_online_cpus()); + + return log * (32UL * 1024 * 1024 / PAGE_SIZE); +} + +static atomic_t vmap_lazy_nr = ATOMIC_INIT(0); + +/* + * Purges all lazily-freed vmap areas. + * + * If sync is 0 then don't purge if there is already a purge in progress. + * If force_flush is 1, then flush kernel TLBs between *start and *end even + * if we found no lazy vmap areas to unmap (callers can use this to optimise + * their own TLB flushing). + * Returns with *start = min(*start, lowest purged address) + * *end = max(*end, highest purged address) + */ +static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end, + int sync, int force_flush) +{ + static DEFINE_SPINLOCK(purge_lock); + LIST_HEAD(valist); + struct vmap_area *va; + int nr = 0; + + /* + * If sync is 0 but force_flush is 1, we'll go sync anyway but callers + * should not expect such behaviour. This just simplifies locking for + * the case that isn't actually used at the moment anyway. + */ + if (!sync && !force_flush) { + if (!spin_trylock(&purge_lock)) + return; + } else + spin_lock(&purge_lock); + + rcu_read_lock(); + list_for_each_entry_rcu(va, &vmap_area_list, list) { + if (va->flags & VM_LAZY_FREE) { + if (va->va_start < *start) + *start = va->va_start; + if (va->va_end > *end) + *end = va->va_end; + nr += (va->va_end - va->va_start) >> PAGE_SHIFT; + unmap_vmap_area(va); + list_add_tail(&va->purge_list, &valist); + va->flags |= VM_LAZY_FREEING; + va->flags &= ~VM_LAZY_FREE; + } + } + rcu_read_unlock(); + + if (nr) { + BUG_ON(nr > atomic_read(&vmap_lazy_nr)); + atomic_sub(nr, &vmap_lazy_nr); + } + + if (nr || force_flush) + flush_tlb_kernel_range(*start, *end); + + if (nr) { + spin_lock(&vmap_area_lock); + list_for_each_entry(va, &valist, purge_list) + __free_vmap_area(va); + spin_unlock(&vmap_area_lock); + } + spin_unlock(&purge_lock); +} + +/* + * Kick off a purge of the outstanding lazy areas. + */ +static void purge_vmap_area_lazy(void) +{ + unsigned long start = ULONG_MAX, end = 0; + + __purge_vmap_area_lazy(&start, &end, 0, 0); +} + +/* + * Free and unmap a vmap area + */ +static void free_unmap_vmap_area(struct vmap_area *va) +{ + va->flags |= VM_LAZY_FREE; + atomic_add((va->va_end - va->va_start) >> PAGE_SHIFT, &vmap_lazy_nr); + if (unlikely(atomic_read(&vmap_lazy_nr) > lazy_max_pages())) + purge_vmap_area_lazy(); +} + +static struct vmap_area *find_vmap_area(unsigned long addr) +{ + struct vmap_area *va; + + spin_lock(&vmap_area_lock); + va = __find_vmap_area(addr); + spin_unlock(&vmap_area_lock); + + return va; +} + +static void free_unmap_vmap_area_addr(unsigned long addr) +{ + struct vmap_area *va; + + va = find_vmap_area(addr); + BUG_ON(!va); + free_unmap_vmap_area(va); +} + + +/*** Per cpu kva allocator ***/ + +/* + * vmap space is limited especially on 32 bit architectures. Ensure there is + * room for at least 16 percpu vmap blocks per CPU. + */ +/* + * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able + * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess + * instead (we just need a rough idea) + */ +#if BITS_PER_LONG == 32 +#define VMALLOC_SPACE (128UL*1024*1024) +#else +#define VMALLOC_SPACE (128UL*1024*1024*1024) +#endif + +#define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE) +#define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */ +#define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */ +#define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2) +#define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */ +#define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */ +#define VMAP_BBMAP_BITS VMAP_MIN(VMAP_BBMAP_BITS_MAX, \ + VMAP_MAX(VMAP_BBMAP_BITS_MIN, \ + VMALLOC_PAGES / NR_CPUS / 16)) + +#define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE) + +struct vmap_block_queue { + spinlock_t lock; + struct list_head free; + struct list_head dirty; + unsigned int nr_dirty; +}; + +struct vmap_block { + spinlock_t lock; + struct vmap_area *va; + struct vmap_block_queue *vbq; + unsigned long free, dirty; + DECLARE_BITMAP(alloc_map, VMAP_BBMAP_BITS); + DECLARE_BITMAP(dirty_map, VMAP_BBMAP_BITS); + union { + struct { + struct list_head free_list; + struct list_head dirty_list; + }; + struct rcu_head rcu_head; + }; +}; + +/* Queue of free and dirty vmap blocks, for allocation and flushing purposes */ +static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue); + +/* + * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block + * in the free path. Could get rid of this if we change the API to return a + * "cookie" from alloc, to be passed to free. But no big deal yet. + */ +static DEFINE_SPINLOCK(vmap_block_tree_lock); +static RADIX_TREE(vmap_block_tree, GFP_ATOMIC); + +/* + * We should probably have a fallback mechanism to allocate virtual memory + * out of partially filled vmap blocks. However vmap block sizing should be + * fairly reasonable according to the vmalloc size, so it shouldn't be a + * big problem. + */ + +static unsigned long addr_to_vb_idx(unsigned long addr) +{ + addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1); + addr /= VMAP_BLOCK_SIZE; + return addr; +} + +static struct vmap_block *new_vmap_block(gfp_t gfp_mask) +{ + struct vmap_block_queue *vbq; + struct vmap_block *vb; + struct vmap_area *va; + unsigned long vb_idx; + int node, err; + + node = numa_node_id(); + + vb = kmalloc_node(sizeof(struct vmap_block), + gfp_mask & GFP_RECLAIM_MASK, node); + if (unlikely(!vb)) + return ERR_PTR(-ENOMEM); + + va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE, + VMALLOC_START, VMALLOC_END, + node, gfp_mask); + if (unlikely(IS_ERR(va))) { + kfree(vb); + return ERR_PTR(PTR_ERR(va)); + } + + err = radix_tree_preload(gfp_mask); + if (unlikely(err)) { + kfree(vb); + free_vmap_area(va); + return ERR_PTR(err); + } + + spin_lock_init(&vb->lock); + vb->va = va; + vb->free = VMAP_BBMAP_BITS; + vb->dirty = 0; + bitmap_zero(vb->alloc_map, VMAP_BBMAP_BITS); + bitmap_zero(vb->dirty_map, VMAP_BBMAP_BITS); + INIT_LIST_HEAD(&vb->free_list); + INIT_LIST_HEAD(&vb->dirty_list); + + vb_idx = addr_to_vb_idx(va->va_start); + spin_lock(&vmap_block_tree_lock); + err = radix_tree_insert(&vmap_block_tree, vb_idx, vb); + spin_unlock(&vmap_block_tree_lock); + BUG_ON(err); + radix_tree_preload_end(); + + vbq = &get_cpu_var(vmap_block_queue); + vb->vbq = vbq; + spin_lock(&vbq->lock); + list_add(&vb->free_list, &vbq->free); + spin_unlock(&vbq->lock); + put_cpu_var(vmap_cpu_blocks); + + return vb; +} + +static void rcu_free_vb(struct rcu_head *head) +{ + struct vmap_block *vb = container_of(head, struct vmap_block, rcu_head); + + kfree(vb); +} + +static void free_vmap_block(struct vmap_block *vb) +{ + struct vmap_block *tmp; + unsigned long vb_idx; + + spin_lock(&vb->vbq->lock); + if (!list_empty(&vb->free_list)) + list_del(&vb->free_list); + if (!list_empty(&vb->dirty_list)) + list_del(&vb->dirty_list); + spin_unlock(&vb->vbq->lock); + + vb_idx = addr_to_vb_idx(vb->va->va_start); + spin_lock(&vmap_block_tree_lock); + tmp = radix_tree_delete(&vmap_block_tree, vb_idx); + spin_unlock(&vmap_block_tree_lock); + BUG_ON(tmp != vb); + + free_unmap_vmap_area(vb->va); + call_rcu(&vb->rcu_head, rcu_free_vb); +} + +static void *vb_alloc(unsigned long size, gfp_t gfp_mask) +{ + struct vmap_block_queue *vbq; + struct vmap_block *vb; + unsigned long addr = 0; + unsigned int order; + + BUG_ON(size & ~PAGE_MASK); + BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC); + order = get_order(size); + +again: + rcu_read_lock(); + vbq = &get_cpu_var(vmap_block_queue); + list_for_each_entry_rcu(vb, &vbq->free, free_list) { + int i; + + spin_lock(&vb->lock); + i = bitmap_find_free_region(vb->alloc_map, + VMAP_BBMAP_BITS, order); + + if (i >= 0) { + addr = vb->va->va_start + (i << PAGE_SHIFT); + BUG_ON(addr_to_vb_idx(addr) != + addr_to_vb_idx(vb->va->va_start)); + vb->free -= 1UL << order; + if (vb->free == 0) { + spin_lock(&vbq->lock); + list_del_init(&vb->free_list); + spin_unlock(&vbq->lock); + } + spin_unlock(&vb->lock); + break; + } + spin_unlock(&vb->lock); + } + put_cpu_var(vmap_cpu_blocks); + rcu_read_unlock(); + + if (!addr) { + vb = new_vmap_block(gfp_mask); + if (IS_ERR(vb)) + return vb; + goto again; + } + + return (void *)addr; +} + +static void vb_free(const void *addr, unsigned long size) +{ + unsigned long offset; + unsigned long vb_idx; + unsigned int order; + struct vmap_block *vb; + + BUG_ON(size & ~PAGE_MASK); + BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC); + order = get_order(size); + + offset = (unsigned long)addr & (VMAP_BLOCK_SIZE - 1); + + vb_idx = addr_to_vb_idx((unsigned long)addr); + rcu_read_lock(); + vb = radix_tree_lookup(&vmap_block_tree, vb_idx); + rcu_read_unlock(); + BUG_ON(!vb); + + spin_lock(&vb->lock); + bitmap_allocate_region(vb->dirty_map, offset >> PAGE_SHIFT, order); + if (!vb->dirty) { + spin_lock(&vb->vbq->lock); + list_add(&vb->dirty_list, &vb->vbq->dirty); + spin_unlock(&vb->vbq->lock); + } + vb->dirty += 1UL << order; + if (vb->dirty == VMAP_BBMAP_BITS) { + BUG_ON(vb->free || !list_empty(&vb->free_list)); + spin_unlock(&vb->lock); + free_vmap_block(vb); + } else + spin_unlock(&vb->lock); +} + +/** + * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer + * + * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily + * to amortize TLB flushing overheads. What this means is that any page you + * have now, may, in a former life, have been mapped into kernel virtual + * address by the vmap layer and so there might be some CPUs with TLB entries + * still referencing that page (additional to the regular 1:1 kernel mapping). + * + * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can + * be sure that none of the pages we have control over will have any aliases + * from the vmap layer. + */ +void vm_unmap_aliases(void) +{ + unsigned long start = ULONG_MAX, end = 0; + int cpu; + int flush = 0; + + for_each_possible_cpu(cpu) { + struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu); + struct vmap_block *vb; + + rcu_read_lock(); + list_for_each_entry_rcu(vb, &vbq->free, free_list) { + int i; + + spin_lock(&vb->lock); + i = find_first_bit(vb->dirty_map, VMAP_BBMAP_BITS); + while (i < VMAP_BBMAP_BITS) { + unsigned long s, e; + int j; + j = find_next_zero_bit(vb->dirty_map, + VMAP_BBMAP_BITS, i); + + s = vb->va->va_start + (i << PAGE_SHIFT); + e = vb->va->va_start + (j << PAGE_SHIFT); + vunmap_page_range(s, e); + flush = 1; + + if (s < start) + start = s; + if (e > end) + end = e; + + i = j; + i = find_next_bit(vb->dirty_map, + VMAP_BBMAP_BITS, i); + } + spin_unlock(&vb->lock); + } + rcu_read_unlock(); + } + + __purge_vmap_area_lazy(&start, &end, 1, flush); +} +EXPORT_SYMBOL_GPL(vm_unmap_aliases); + +/** + * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram + * @mem: the pointer returned by vm_map_ram + * @count: the count passed to that vm_map_ram call (cannot unmap partial) + */ +void vm_unmap_ram(const void *mem, unsigned int count) +{ + unsigned long size = count << PAGE_SHIFT; + unsigned long addr = (unsigned long)mem; + + BUG_ON(!addr); + BUG_ON(addr < VMALLOC_START); + BUG_ON(addr > VMALLOC_END); + BUG_ON(addr & (PAGE_SIZE-1)); + + debug_check_no_locks_freed(mem, size); + + if (likely(count <= VMAP_MAX_ALLOC)) + vb_free(mem, size); + else + free_unmap_vmap_area_addr(addr); +} +EXPORT_SYMBOL(vm_unmap_ram); + +/** + * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space) + * @pages: an array of pointers to the pages to be mapped + * @count: number of pages + * @node: prefer to allocate data structures on this node + * @prot: memory protection to use. PAGE_KERNEL for regular RAM + * @returns: a pointer to the address that has been mapped, or NULL on failure + */ +void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot) +{ + unsigned long size = count << PAGE_SHIFT; unsigned long addr; + void *mem; + + if (likely(count <= VMAP_MAX_ALLOC)) { + mem = vb_alloc(size, GFP_KERNEL); + if (IS_ERR(mem)) + return NULL; + addr = (unsigned long)mem; + } else { + struct vmap_area *va; + va = alloc_vmap_area(size, PAGE_SIZE, + VMALLOC_START, VMALLOC_END, node, GFP_KERNEL); + if (IS_ERR(va)) + return NULL; + + addr = va->va_start; + mem = (void *)addr; + } + if (vmap_page_range(addr, addr + size, prot, pages) < 0) { + vm_unmap_ram(mem, count); + return NULL; + } + return mem; +} +EXPORT_SYMBOL(vm_map_ram); + +void __init vmalloc_init(void) +{ + int i; + + for_each_possible_cpu(i) { + struct vmap_block_queue *vbq; + + vbq = &per_cpu(vmap_block_queue, i); + spin_lock_init(&vbq->lock); + INIT_LIST_HEAD(&vbq->free); + INIT_LIST_HEAD(&vbq->dirty); + vbq->nr_dirty = 0; + } +} + +void unmap_kernel_range(unsigned long addr, unsigned long size) +{ + unsigned long end = addr + size; + vunmap_page_range(addr, end); + flush_tlb_kernel_range(addr, end); +} + +int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages) +{ + unsigned long addr = (unsigned long)area->addr; + unsigned long end = addr + area->size - PAGE_SIZE; + int err; + + err = vmap_page_range(addr, end, prot, *pages); + if (err > 0) { + *pages += err; + err = 0; + } + + return err; +} +EXPORT_SYMBOL_GPL(map_vm_area); + +/*** Old vmalloc interfaces ***/ +DEFINE_RWLOCK(vmlist_lock); +struct vm_struct *vmlist; + +static struct vm_struct *__get_vm_area_node(unsigned long size, + unsigned long flags, unsigned long start, unsigned long end, + int node, gfp_t gfp_mask, void *caller) +{ + static struct vmap_area *va; + struct vm_struct *area; + struct vm_struct *tmp, **p; + unsigned long align = 1; BUG_ON(in_interrupt()); if (flags & VM_IOREMAP) { @@ -232,13 +976,12 @@ __get_vm_area_node(unsigned long size, unsigned long flags, unsigned long start, align = 1ul << bit; } - addr = ALIGN(start, align); + size = PAGE_ALIGN(size); if (unlikely(!size)) return NULL; area = kmalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node); - if (unlikely(!area)) return NULL; @@ -247,48 +990,32 @@ __get_vm_area_node(unsigned long size, unsigned long flags, unsigned long start, */ size += PAGE_SIZE; - write_lock(&vmlist_lock); - for (p = &vmlist; (tmp = *p) != NULL ;p = &tmp->next) { - if ((unsigned long)tmp->addr < addr) { - if((unsigned long)tmp->addr + tmp->size >= addr) - addr = ALIGN(tmp->size + - (unsigned long)tmp->addr, align); - continue; - } - if ((size + addr) < addr) - goto out; - if (size + addr <= (unsigned long)tmp->addr) - goto found; - addr = ALIGN(tmp->size + (unsigned long)tmp->addr, align); - if (addr > end - size) - goto out; + va = alloc_vmap_area(size, align, start, end, node, gfp_mask); + if (IS_ERR(va)) { + kfree(area); + return NULL; } - if ((size + addr) < addr) - goto out; - if (addr > end - size) - goto out; - -found: - area->next = *p; - *p = area; area->flags = flags; - area->addr = (void *)addr; + area->addr = (void *)va->va_start; area->size = size; area->pages = NULL; area->nr_pages = 0; area->phys_addr = 0; area->caller = caller; + va->private = area; + va->flags |= VM_VM_AREA; + + write_lock(&vmlist_lock); + for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) { + if (tmp->addr >= area->addr) + break; + } + area->next = *p; + *p = area; write_unlock(&vmlist_lock); return area; - -out: - write_unlock(&vmlist_lock); - kfree(area); - if (printk_ratelimit()) - printk(KERN_WARNING "allocation failed: out of vmalloc space - use vmalloc=<size> to increase size.\n"); - return NULL; } struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, @@ -328,39 +1055,15 @@ struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags, gfp_mask, __builtin_return_address(0)); } -/* Caller must hold vmlist_lock */ -static struct vm_struct *__find_vm_area(const void *addr) +static struct vm_struct *find_vm_area(const void *addr) { - struct vm_struct *tmp; + struct vmap_area *va; - for (tmp = vmlist; tmp != NULL; tmp = tmp->next) { - if (tmp->addr == addr) - break; - } - - return tmp; -} - -/* Caller must hold vmlist_lock */ -static struct vm_struct *__remove_vm_area(const void *addr) -{ - struct vm_struct **p, *tmp; + va = find_vmap_area((unsigned long)addr); + if (va && va->flags & VM_VM_AREA) + return va->private; - for (p = &vmlist ; (tmp = *p) != NULL ;p = &tmp->next) { - if (tmp->addr == addr) - goto found; - } return NULL; - -found: - unmap_vm_area(tmp); - *p = tmp->next; - - /* - * Remove the guard page. - */ - tmp->size -= PAGE_SIZE; - return tmp; } /** @@ -373,11 +1076,24 @@ found: */ struct vm_struct *remove_vm_area(const void *addr) { - struct vm_struct *v; - write_lock(&vmlist_lock); - v = __remove_vm_area(addr); - write_unlock(&vmlist_lock); - return v; + struct vmap_area *va; + + va = find_vmap_area((unsigned long)addr); + if (va && va->flags & VM_VM_AREA) { + struct vm_struct *vm = va->private; + struct vm_struct *tmp, **p; + free_unmap_vmap_area(va); + vm->size -= PAGE_SIZE; + + write_lock(&vmlist_lock); + for (p = &vmlist; (tmp = *p) != vm; p = &tmp->next) + ; + *p = tmp->next; + write_unlock(&vmlist_lock); + + return vm; + } + return NULL; } static void __vunmap(const void *addr, int deallocate_pages) @@ -487,6 +1203,8 @@ void *vmap(struct page **pages, unsigned int count, } EXPORT_SYMBOL(vmap); +static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, + int node, void *caller); static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot, int node, void *caller) { @@ -613,10 +1331,8 @@ void *vmalloc_user(unsigned long size) ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL); if (ret) { - write_lock(&vmlist_lock); - area = __find_vm_area(ret); + area = find_vm_area(ret); area->flags |= VM_USERMAP; - write_unlock(&vmlist_lock); } return ret; } @@ -696,10 +1412,8 @@ void *vmalloc_32_user(unsigned long size) ret = __vmalloc(size, GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL); if (ret) { - write_lock(&vmlist_lock); - area = __find_vm_area(ret); + area = find_vm_area(ret); area->flags |= VM_USERMAP; - write_unlock(&vmlist_lock); } return ret; } @@ -800,26 +1514,25 @@ int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, struct vm_struct *area; unsigned long uaddr = vma->vm_start; unsigned long usize = vma->vm_end - vma->vm_start; - int ret; if ((PAGE_SIZE-1) & (unsigned long)addr) return -EINVAL; - read_lock(&vmlist_lock); - area = __find_vm_area(addr); + area = find_vm_area(addr); if (!area) - goto out_einval_locked; + return -EINVAL; if (!(area->flags & VM_USERMAP)) - goto out_einval_locked; + return -EINVAL; if (usize + (pgoff << PAGE_SHIFT) > area->size - PAGE_SIZE) - goto out_einval_locked; - read_unlock(&vmlist_lock); + return -EINVAL; addr += pgoff << PAGE_SHIFT; do { struct page *page = vmalloc_to_page(addr); + int ret; + ret = vm_insert_page(vma, uaddr, page); if (ret) return ret; @@ -832,11 +1545,7 @@ int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, /* Prevent "things" like memory migration? VM_flags need a cleanup... */ vma->vm_flags |= VM_RESERVED; - return ret; - -out_einval_locked: - read_unlock(&vmlist_lock); - return -EINVAL; + return 0; } EXPORT_SYMBOL(remap_vmalloc_range); |