1 /* 2 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 3 * All Rights Reserved. 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it would be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 #include <linux/mm.h> 19 #include <linux/highmem.h> 20 #include <linux/slab.h> 21 #include <linux/swap.h> 22 #include <linux/blkdev.h> 23 #include <linux/backing-dev.h> 24 #include "kmem.h" 25 #include "xfs_message.h" 26 27 /* 28 * Greedy allocation. May fail and may return vmalloced memory. 29 */ 30 void * 31 kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize) 32 { 33 void *ptr; 34 size_t kmsize = maxsize; 35 36 while (!(ptr = vzalloc(kmsize))) { 37 if ((kmsize >>= 1) <= minsize) 38 kmsize = minsize; 39 } 40 if (ptr) 41 *size = kmsize; 42 return ptr; 43 } 44 45 void * 46 kmem_alloc(size_t size, xfs_km_flags_t flags) 47 { 48 int retries = 0; 49 gfp_t lflags = kmem_flags_convert(flags); 50 void *ptr; 51 52 do { 53 ptr = kmalloc(size, lflags); 54 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) 55 return ptr; 56 if (!(++retries % 100)) 57 xfs_err(NULL, 58 "possible memory allocation deadlock in %s (mode:0x%x)", 59 __func__, lflags); 60 congestion_wait(BLK_RW_ASYNC, HZ/50); 61 } while (1); 62 } 63 64 void * 65 kmem_zalloc_large(size_t size, xfs_km_flags_t flags) 66 { 67 unsigned noio_flag = 0; 68 void *ptr; 69 gfp_t lflags; 70 71 ptr = kmem_zalloc(size, flags | KM_MAYFAIL); 72 if (ptr) 73 return ptr; 74 75 /* 76 * __vmalloc() will allocate data pages and auxillary structures (e.g. 77 * pagetables) with GFP_KERNEL, yet we may be under GFP_NOFS context 78 * here. Hence we need to tell memory reclaim that we are in such a 79 * context via PF_MEMALLOC_NOIO to prevent memory reclaim re-entering 80 * the filesystem here and potentially deadlocking. 81 */ 82 if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS)) 83 noio_flag = memalloc_noio_save(); 84 85 lflags = kmem_flags_convert(flags); 86 ptr = __vmalloc(size, lflags | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL); 87 88 if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS)) 89 memalloc_noio_restore(noio_flag); 90 91 return ptr; 92 } 93 94 void 95 kmem_free(const void *ptr) 96 { 97 if (!is_vmalloc_addr(ptr)) { 98 kfree(ptr); 99 } else { 100 vfree(ptr); 101 } 102 } 103 104 void * 105 kmem_realloc(const void *ptr, size_t newsize, size_t oldsize, 106 xfs_km_flags_t flags) 107 { 108 void *new; 109 110 new = kmem_alloc(newsize, flags); 111 if (ptr) { 112 if (new) 113 memcpy(new, ptr, 114 ((oldsize < newsize) ? oldsize : newsize)); 115 kmem_free(ptr); 116 } 117 return new; 118 } 119 120 void * 121 kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags) 122 { 123 int retries = 0; 124 gfp_t lflags = kmem_flags_convert(flags); 125 void *ptr; 126 127 do { 128 ptr = kmem_cache_alloc(zone, lflags); 129 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) 130 return ptr; 131 if (!(++retries % 100)) 132 xfs_err(NULL, 133 "possible memory allocation deadlock in %s (mode:0x%x)", 134 __func__, lflags); 135 congestion_wait(BLK_RW_ASYNC, HZ/50); 136 } while (1); 137 } 138