fs/ntfs/malloc.h

   1 /*
   2  * malloc.h - NTFS kernel memory handling. Part of the Linux-NTFS project.
   3  *
   4  * Copyright (c) 2001-2005 Anton Altaparmakov
   5  *
   6  * This program/include file is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as published
   8  * by the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program/include file is distributed in the hope that it will be
  12  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program (in the main directory of the Linux-NTFS
  18  * distribution in the file COPYING); if not, write to the Free Software
  19  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #ifndef _LINUX_NTFS_MALLOC_H
  23 #define _LINUX_NTFS_MALLOC_H
  24
  25 #include <linux/vmalloc.h>
  26 #include <linux/slab.h>
  27 #include <linux/highmem.h>
  28
  29 /**
  30  * __ntfs_malloc - allocate memory in multiples of pages
  31  * @size:       number of bytes to allocate
  32  * @gfp_mask:   extra flags for the allocator
  33  *
  34  * Internal function.  You probably want ntfs_malloc_nofs()...
  35  *
  36  * Allocates @size bytes of memory, rounded up to multiples of PAGE_SIZE and
  37  * returns a pointer to the allocated memory.
  38  *
  39  * If there was insufficient memory to complete the request, return NULL.
  40  * Depending on @gfp_mask the allocation may be guaranteed to succeed.
  41  */
  42 static inline void *__ntfs_malloc(unsigned long size, gfp_t gfp_mask)
  43 {
  44         if (likely(size <= PAGE_SIZE)) {
  45                 BUG_ON(!size);
  46                 /* kmalloc() has per-CPU caches so is faster for now. */
  47                 return kmalloc(PAGE_SIZE, gfp_mask & ~__GFP_HIGHMEM);
  48                 /* return (void *)__get_free_page(gfp_mask); */
  49         }
  50         if (likely(size >> PAGE_SHIFT < num_physpages))
  51                 return __vmalloc(size, gfp_mask, PAGE_KERNEL);
  52         return NULL;
  53 }
  54
  55 /**
  56  * ntfs_malloc_nofs - allocate memory in multiples of pages
  57  * @size:       number of bytes to allocate
  58  *
  59  * Allocates @size bytes of memory, rounded up to multiples of PAGE_SIZE and
  60  * returns a pointer to the allocated memory.
  61  *
  62  * If there was insufficient memory to complete the request, return NULL.
  63  */
  64 static inline void *ntfs_malloc_nofs(unsigned long size)
  65 {
  66         return __ntfs_malloc(size, GFP_NOFS | __GFP_HIGHMEM);
  67 }
  68
  69 /**
  70  * ntfs_malloc_nofs_nofail - allocate memory in multiples of pages
  71  * @size:       number of bytes to allocate
  72  *
  73  * Allocates @size bytes of memory, rounded up to multiples of PAGE_SIZE and
  74  * returns a pointer to the allocated memory.
  75  *
  76  * This function guarantees that the allocation will succeed.  It will sleep
  77  * for as long as it takes to complete the allocation.
  78  *
  79  * If there was insufficient memory to complete the request, return NULL.
  80  */
  81 static inline void *ntfs_malloc_nofs_nofail(unsigned long size)
  82 {
  83         return __ntfs_malloc(size, GFP_NOFS | __GFP_HIGHMEM | __GFP_NOFAIL);
  84 }
  85
  86 static inline void ntfs_free(void *addr)
  87 {
  88         if (likely(((unsigned long)addr < VMALLOC_START) ||
  89                         ((unsigned long)addr >= VMALLOC_END ))) {
  90                 kfree(addr);
  91                 /* free_page((unsigned long)addr); */
  92                 return;
  93         }
  94         vfree(addr);
  95 }
  96
  97 #endif /* _LINUX_NTFS_MALLOC_H */