/* * linux/mm/vmalloc.c * * Copyright (C) 1993 Linus Torvalds * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 * SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000 * Major rework to support vmap/vunmap, Christoph Hellwig, SGI, August 2002 * Numa awareness, Christoph Lameter, SGI, June 2005 */ #include <linux/mm.h>#include <linux/module.h>#include <linux/highmem.h>#include <linux/slab.h>#include <linux/spinlock.h>#include <linux/interrupt.h> #include <linux/vmalloc.h> #include <asm/uaccess.h>#include <asm/tlbflush.h> DEFINE_RWLOCK(vmlist_lock);struct vm_struct *vmlist; static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end){ pte_t *pte; pte = pte_offset_kernel(pmd, addr); do { pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte); WARN_ON(!pte_none(ptent) && !pte_present(ptent)); } while (pte++, addr += PAGE_SIZE, addr != end);} static inline void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end){ pmd_t *pmd; unsigned long next; pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); if (pmd_none_or_clear_bad(pmd)) continue; vunmap_pte_range(pmd, addr, next); } while (pmd++, addr = next, addr != end);} static inline void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end){ pud_t *pud; unsigned long next; pud = pud_offset(pgd, addr); do { next = pud_addr_end(addr, end); if (pud_none_or_clear_bad(pud)) continue; vunmap_pmd_range(pud, addr, next); } while (pud++, addr = next, addr != end);} void unmap_vm_area(struct vm_struct *area){ pgd_t *pgd; unsigned long next; unsigned long addr = (unsigned long) area->addr; unsigned long end = addr + area->size; BUG_ON(addr >= end); pgd = pgd_offset_k(addr); flush_cache_vunmap(addr, end); do { next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) continue; vunmap_pud_range(pgd, addr, next); } while (pgd++, addr = next, addr != end); flush_tlb_kernel_range((unsigned long) area->addr, end);} static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t prot, struct page ***pages){ pte_t *pte; pte = pte_alloc_kernel(pmd, addr); if (!pte) return -ENOMEM; do { struct page *page = **pages; WARN_ON(!pte_none(*pte)); if (!page) return -ENOMEM; set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); (*pages)++; } 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){ pmd_t *pmd; unsigned long next; pmd = pmd_alloc(&init_mm, pud, addr); if (!pmd) return -ENOMEM; do { next = pmd_addr_end(addr, end); if (vmap_pte_range(pmd, addr, next, prot, pages)) 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){ pud_t *pud; unsigned long next; pud = pud_alloc(&init_mm, pgd, addr); if (!pud) return -ENOMEM; do { next = pud_addr_end(addr, end); if (vmap_pmd_range(pud, addr, next, prot, pages)) return -ENOMEM; } while (pud++, addr = next, addr != end); return 0;} int map_vm_area(struct vm_struct *area, 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; 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); if (err) break; } while (pgd++, addr = next, addr != end); flush_cache_vmap((unsigned long) area->addr, end); return err;} struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long flags, unsigned long start, unsigned long end, int node){ struct vm_struct **p, *tmp, *area; unsigned long align = 1; unsigned long addr; if (flags & VM_IOREMAP) { int bit = fls(size); if (bit > IOREMAP_MAX_ORDER) bit = IOREMAP_MAX_ORDER; else if (bit < PAGE_SHIFT) bit = PAGE_SHIFT; align = 1ul << bit; } addr = ALIGN(start, align); size = PAGE_ALIGN(size); area = kmalloc_node(sizeof(*area), GFP_KERNEL, node); if (unlikely(!area)) return NULL; if (unlikely(!size)) { kfree (area); return NULL; } /* * We always allocate a guard page. */ 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; } found: area->next = *p; *p = area; area->flags = flags; area->addr = (void *)addr; area->size = size; area->pages = NULL; area->nr_pages = 0; area->phys_addr = 0; 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, unsigned long start, unsigned long end){ return __get_vm_area_node(size, flags, start, end, -1);} /** * get_vm_area - reserve a contingous kernel virtual area * * @size: size of the area * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC * * Search an area of @size in the kernel virtual mapping area, * and reserved it for out purposes. Returns the area descriptor * on success or %NULL on failure. */struct vm_struct *get_vm_area(unsigned long size, unsigned long flags){ return __get_vm_area(size, flags, VMALLOC_START, VMALLOC_END);} struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags, int node){ return __get_vm_area_node(size, flags, VMALLOC_START, VMALLOC_END, node);} /* Caller must hold vmlist_lock */struct vm_struct *__remove_vm_area(void *addr){ struct vm_struct **p, *tmp; 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;} /** * remove_vm_area - find and remove a contingous kernel virtual area * * @addr: base address * * Search for the kernel VM area starting at @addr, and remove it. * This function returns the found VM area, but using it is NOT safe * on SMP machines, except for its size or flags. */struct vm_struct *remove_vm_area(void *addr){ struct vm_struct *v; write_lock(&vmlist_lock); v = __remove_vm_area(addr); write_unlock(&vmlist_lock); return v;} void __vunmap(void *addr, int deallocate_pages){ struct vm_struct *area; if (!addr) return; if ((PAGE_SIZE-1) & (unsigned long)addr) { printk(KERN_ERR "Trying to vfree() bad address (%p)\n", addr); WARN_ON(1); return; } area = remove_vm_area(addr); if (unlikely(!area)) { printk(KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", addr); WARN_ON(1); return; } if (deallocate_pages) { int i; for (i = 0; i < area->nr_pages; i++) { if (unlikely(!area->pages[i])) BUG(); __free_page(area->pages[i]); } if (area->nr_pages > PAGE_SIZE/sizeof(struct page *)) vfree(area->pages); else kfree(area->pages); } kfree(area); return;} /** * vfree - release memory allocated by vmalloc() * * @addr: memory base address * * Free the virtually contiguous memory area starting at @addr, as * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is * NULL, no operation is performed. * * Must not be called in interrupt context. */void vfree(void *addr){ BUG_ON(in_interrupt()); __vunmap(addr, 1);}EXPORT_SYMBOL(vfree); /** * vunmap - release virtual mapping obtained by vmap() * * @addr: memory base address * * Free the virtually contiguous memory area starting at @addr, * which was created from the page array passed to vmap(). * * Must not be called in interrupt context. */void vunmap(void *addr){ BUG_ON(in_interrupt()); __vunmap(addr, 0);}EXPORT_SYMBOL(vunmap); /** * vmap - map an array of pages into virtually contiguous space * * @pages: array of page pointers * @count: number of pages to map * @flags: vm_area->flags * @prot: page protection for the mapping * * Maps @count pages from @pages into contiguous kernel virtual * space. */void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_t prot){ struct vm_struct *area; if (count > num_physpages) return NULL; area = get_vm_area((count << PAGE_SHIFT), flags); if (!area) return NULL; if (map_vm_area(area, prot, &pages)) { vunmap(area->addr); return NULL; } return area->addr;}EXPORT_SYMBOL(vmap); void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot, int node){ struct page **pages; unsigned int nr_pages, array_size, i; nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT; array_size = (nr_pages * sizeof(struct page *)); area->nr_pages = nr_pages; /* Please note that the recursion is strictly bounded. */ if (array_size > PAGE_SIZE) pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node); else pages = kmalloc_node(array_size, (gfp_mask & ~__GFP_HIGHMEM), node); area->pages = pages; if (!area->pages) { remove_vm_area(area->addr); kfree(area); return NULL; } memset(area->pages, 0, array_size); for (i = 0; i < area->nr_pages; i++) { if (node < 0) area->pages[i] = alloc_page(gfp_mask); else area->pages[i] = alloc_pages_node(node, gfp_mask, 0); if (unlikely(!area->pages[i])) { /* Successfully allocated i pages, free them in __vunmap() */ area->nr_pages = i; goto fail; } } if (map_vm_area(area, prot, &pages)) goto fail; return area->addr; fail: vfree(area->addr); return NULL;} void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot){ return __vmalloc_area_node(area, gfp_mask, prot, -1);} /** * __vmalloc_node - allocate virtually contiguous memory * * @size: allocation size * @gfp_mask: flags for the page level allocator * @prot: protection mask for the allocated pages * @node: node to use for allocation or -1 * * Allocate enough pages to cover @size from the page level * allocator with @gfp_mask flags. Map them into contiguous * kernel virtual space, using a pagetable protection of @prot. */void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, int node){ struct vm_struct *area; size = PAGE_ALIGN(size); if (!size || (size >> PAGE_SHIFT) > num_physpages) return NULL; area = get_vm_area_node(size, VM_ALLOC, node); if (!area) return NULL; return __vmalloc_area_node(area, gfp_mask, prot, node);}EXPORT_SYMBOL(__vmalloc_node); void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot){ return __vmalloc_node(size, gfp_mask, prot, -1);}EXPORT_SYMBOL(__vmalloc); /** * vmalloc - allocate virtually contiguous memory * * @size: allocation size * * Allocate enough pages to cover @size from the page level * allocator and map them into contiguous kernel virtual space. * * For tight cotrol over page level allocator and protection flags * use __vmalloc() instead. */void *vmalloc(unsigned long size)Lines 1–500 of 633. Load more
/* * linux/mm/vmalloc.c * * Copyright (C) 1993 Linus Torvalds * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 * SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000 * Major rework to support vmap/vunmap, Christoph Hellwig, SGI, August 2002 * Numa awareness, Christoph Lameter, SGI, June 2005 */ #include <linux/mm.h> #include <linux/module.h> #include <linux/highmem.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/interrupt.h> #include <linux/vmalloc.h> #include <asm/uaccess.h> #include <asm/tlbflush.h> DEFINE_RWLOCK(vmlist_lock); struct vm_struct *vmlist; static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) { pte_t *pte; pte = pte_offset_kernel(pmd, addr); do { pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte); WARN_ON(!pte_none(ptent) && !pte_present(ptent)); } while (pte++, addr += PAGE_SIZE, addr != end); } static inline void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end) { pmd_t *pmd; unsigned long next; pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); if (pmd_none_or_clear_bad(pmd)) continue; vunmap_pte_range(pmd, addr, next); } while (pmd++, addr = next, addr != end); } static inline void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end) { pud_t *pud; unsigned long next; pud = pud_offset(pgd, addr); do { next = pud_addr_end(addr, end); if (pud_none_or_clear_bad(pud)) continue; vunmap_pmd_range(pud, addr, next); } while (pud++, addr = next, addr != end); } void unmap_vm_area(struct vm_struct *area) { pgd_t *pgd; unsigned long next; unsigned long addr = (unsigned long) area->addr; unsigned long end = addr + area->size; BUG_ON(addr >= end); pgd = pgd_offset_k(addr); flush_cache_vunmap(addr, end); do { next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) continue; vunmap_pud_range(pgd, addr, next); } while (pgd++, addr = next, addr != end); flush_tlb_kernel_range((unsigned long) area->addr, end); } static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t prot, struct page ***pages) { pte_t *pte; pte = pte_alloc_kernel(pmd, addr); if (!pte) return -ENOMEM; do { struct page *page = **pages; WARN_ON(!pte_none(*pte)); if (!page) return -ENOMEM; set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); (*pages)++; } 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) { pmd_t *pmd; unsigned long next; pmd = pmd_alloc(&init_mm, pud, addr); if (!pmd) return -ENOMEM; do { next = pmd_addr_end(addr, end); if (vmap_pte_range(pmd, addr, next, prot, pages)) 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) { pud_t *pud; unsigned long next; pud = pud_alloc(&init_mm, pgd, addr); if (!pud) return -ENOMEM; do { next = pud_addr_end(addr, end); if (vmap_pmd_range(pud, addr, next, prot, pages)) return -ENOMEM; } while (pud++, addr = next, addr != end); return 0; } int map_vm_area(struct vm_struct *area, 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; 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); if (err) break; } while (pgd++, addr = next, addr != end); flush_cache_vmap((unsigned long) area->addr, end); return err; } struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long flags, unsigned long start, unsigned long end, int node) { struct vm_struct **p, *tmp, *area; unsigned long align = 1; unsigned long addr; if (flags & VM_IOREMAP) { int bit = fls(size); if (bit > IOREMAP_MAX_ORDER) bit = IOREMAP_MAX_ORDER; else if (bit < PAGE_SHIFT) bit = PAGE_SHIFT; align = 1ul << bit; } addr = ALIGN(start, align); size = PAGE_ALIGN(size); area = kmalloc_node(sizeof(*area), GFP_KERNEL, node); if (unlikely(!area)) return NULL; if (unlikely(!size)) { kfree (area); return NULL; } /* * We always allocate a guard page. */ 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; } found: area->next = *p; *p = area; area->flags = flags; area->addr = (void *)addr; area->size = size; area->pages = NULL; area->nr_pages = 0; area->phys_addr = 0; 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, unsigned long start, unsigned long end) { return __get_vm_area_node(size, flags, start, end, -1); } /** * get_vm_area - reserve a contingous kernel virtual area * * @size: size of the area * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC * * Search an area of @size in the kernel virtual mapping area, * and reserved it for out purposes. Returns the area descriptor * on success or %NULL on failure. */ struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) { return __get_vm_area(size, flags, VMALLOC_START, VMALLOC_END); } struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags, int node) { return __get_vm_area_node(size, flags, VMALLOC_START, VMALLOC_END, node); } /* Caller must hold vmlist_lock */ struct vm_struct *__remove_vm_area(void *addr) { struct vm_struct **p, *tmp; 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; } /** * remove_vm_area - find and remove a contingous kernel virtual area * * @addr: base address * * Search for the kernel VM area starting at @addr, and remove it. * This function returns the found VM area, but using it is NOT safe * on SMP machines, except for its size or flags. */ struct vm_struct *remove_vm_area(void *addr) { struct vm_struct *v; write_lock(&vmlist_lock); v = __remove_vm_area(addr); write_unlock(&vmlist_lock); return v; } void __vunmap(void *addr, int deallocate_pages) { struct vm_struct *area; if (!addr) return; if ((PAGE_SIZE-1) & (unsigned long)addr) { printk(KERN_ERR "Trying to vfree() bad address (%p)\n", addr); WARN_ON(1); return; } area = remove_vm_area(addr); if (unlikely(!area)) { printk(KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", addr); WARN_ON(1); return; } if (deallocate_pages) { int i; for (i = 0; i < area->nr_pages; i++) { if (unlikely(!area->pages[i])) BUG(); __free_page(area->pages[i]); } if (area->nr_pages > PAGE_SIZE/sizeof(struct page *)) vfree(area->pages); else kfree(area->pages); } kfree(area); return; } /** * vfree - release memory allocated by vmalloc() * * @addr: memory base address * * Free the virtually contiguous memory area starting at @addr, as * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is * NULL, no operation is performed. * * Must not be called in interrupt context. */ void vfree(void *addr) { BUG_ON(in_interrupt()); __vunmap(addr, 1); } EXPORT_SYMBOL(vfree); /** * vunmap - release virtual mapping obtained by vmap() * * @addr: memory base address * * Free the virtually contiguous memory area starting at @addr, * which was created from the page array passed to vmap(). * * Must not be called in interrupt context. */ void vunmap(void *addr) { BUG_ON(in_interrupt()); __vunmap(addr, 0); } EXPORT_SYMBOL(vunmap); /** * vmap - map an array of pages into virtually contiguous space * * @pages: array of page pointers * @count: number of pages to map * @flags: vm_area->flags * @prot: page protection for the mapping * * Maps @count pages from @pages into contiguous kernel virtual * space. */ void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_t prot) { struct vm_struct *area; if (count > num_physpages) return NULL; area = get_vm_area((count << PAGE_SHIFT), flags); if (!area) return NULL; if (map_vm_area(area, prot, &pages)) { vunmap(area->addr); return NULL; } return area->addr; } EXPORT_SYMBOL(vmap); void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot, int node) { struct page **pages; unsigned int nr_pages, array_size, i; nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT; array_size = (nr_pages * sizeof(struct page *)); area->nr_pages = nr_pages; /* Please note that the recursion is strictly bounded. */ if (array_size > PAGE_SIZE) pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node); else pages = kmalloc_node(array_size, (gfp_mask & ~__GFP_HIGHMEM), node); area->pages = pages; if (!area->pages) { remove_vm_area(area->addr); kfree(area); return NULL; } memset(area->pages, 0, array_size); for (i = 0; i < area->nr_pages; i++) { if (node < 0) area->pages[i] = alloc_page(gfp_mask); else area->pages[i] = alloc_pages_node(node, gfp_mask, 0); if (unlikely(!area->pages[i])) { /* Successfully allocated i pages, free them in __vunmap() */ area->nr_pages = i; goto fail; } } if (map_vm_area(area, prot, &pages)) goto fail; return area->addr; fail: vfree(area->addr); return NULL; } void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot) { return __vmalloc_area_node(area, gfp_mask, prot, -1); } /** * __vmalloc_node - allocate virtually contiguous memory * * @size: allocation size * @gfp_mask: flags for the page level allocator * @prot: protection mask for the allocated pages * @node: node to use for allocation or -1 * * Allocate enough pages to cover @size from the page level * allocator with @gfp_mask flags. Map them into contiguous * kernel virtual space, using a pagetable protection of @prot. */ void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, int node) { struct vm_struct *area; size = PAGE_ALIGN(size); if (!size || (size >> PAGE_SHIFT) > num_physpages) return NULL; area = get_vm_area_node(size, VM_ALLOC, node); if (!area) return NULL; return __vmalloc_area_node(area, gfp_mask, prot, node); } EXPORT_SYMBOL(__vmalloc_node); void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot) { return __vmalloc_node(size, gfp_mask, prot, -1); } EXPORT_SYMBOL(__vmalloc); /** * vmalloc - allocate virtually contiguous memory * * @size: allocation size * * Allocate enough pages to cover @size from the page level * allocator and map them into contiguous kernel virtual space. * * For tight cotrol over page level allocator and protection flags * use __vmalloc() instead. */ void *vmalloc(unsigned long size)