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 "time.h" 25 #include "kmem.h" 26 #include "xfs_message.h" 27 28 /* 29 * Greedy allocation. May fail and may return vmalloced memory. 30 */ 31 void * 32 kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize) 33 { 34 void *ptr; 35 size_t kmsize = maxsize; 36 37 while (!(ptr = vzalloc(kmsize))) { 38 if ((kmsize >>= 1) <= minsize) 39 kmsize = minsize; 40 } 41 if (ptr) 42 *size = kmsize; 43 return ptr; 44 } 45 46 void * 47 kmem_alloc(size_t size, xfs_km_flags_t flags) 48 { 49 int retries = 0; 50 gfp_t lflags = kmem_flags_convert(flags); 51 void *ptr; 52 53 do { 54 ptr = kmalloc(size, lflags); 55 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) 56 return ptr; 57 if (!(++retries % 100)) 58 xfs_err(NULL, 59 "possible memory allocation deadlock in %s (mode:0x%x)", 60 __func__, lflags); 61 congestion_wait(BLK_RW_ASYNC, HZ/50); 62 } while (1); 63 } 64 65 void * 66 kmem_zalloc_large(size_t size, xfs_km_flags_t flags) 67 { 68 unsigned noio_flag = 0; 69 void *ptr; 70 gfp_t lflags; 71 72 ptr = kmem_zalloc(size, flags | KM_MAYFAIL); 73 if (ptr) 74 return ptr; 75 76 /* 77 * __vmalloc() will allocate data pages and auxillary structures (e.g. 78 * pagetables) with GFP_KERNEL, yet we may be under GFP_NOFS context 79 * here. Hence we need to tell memory reclaim that we are in such a 80 * context via PF_MEMALLOC_NOIO to prevent memory reclaim re-entering 81 * the filesystem here and potentially deadlocking. 82 */ 83 if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS)) 84 noio_flag = memalloc_noio_save(); 85 86 lflags = kmem_flags_convert(flags); 87 ptr = __vmalloc(size, lflags | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL); 88 89 if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS)) 90 memalloc_noio_restore(noio_flag); 91 92 return ptr; 93 } 94 95 void 96 kmem_free(const void *ptr) 97 { 98 if (!is_vmalloc_addr(ptr)) { 99 kfree(ptr); 100 } else { 101 vfree(ptr); 102 } 103 } 104 105 void * 106 kmem_realloc(const void *ptr, size_t newsize, size_t oldsize, 107 xfs_km_flags_t flags) 108 { 109 void *new; 110 111 new = kmem_alloc(newsize, flags); 112 if (ptr) { 113 if (new) 114 memcpy(new, ptr, 115 ((oldsize < newsize) ? oldsize : newsize)); 116 kmem_free(ptr); 117 } 118 return new; 119 } 120 121 void * 122 kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags) 123 { 124 int retries = 0; 125 gfp_t lflags = kmem_flags_convert(flags); 126 void *ptr; 127 128 do { 129 ptr = kmem_cache_alloc(zone, lflags); 130 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) 131 return ptr; 132 if (!(++retries % 100)) 133 xfs_err(NULL, 134 "possible memory allocation deadlock in %s (mode:0x%x)", 135 __func__, lflags); 136 congestion_wait(BLK_RW_ASYNC, HZ/50); 137 } while (1); 138 } 139