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 "%s(%u) possible memory allocation deadlock size %u in %s (mode:0x%x)", 59 current->comm, current->pid, 60 (unsigned int)size, __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_realloc(const void *ptr, size_t newsize, size_t oldsize, 97 xfs_km_flags_t flags) 98 { 99 void *new; 100 101 new = kmem_alloc(newsize, flags); 102 if (ptr) { 103 if (new) 104 memcpy(new, ptr, 105 ((oldsize < newsize) ? oldsize : newsize)); 106 kmem_free(ptr); 107 } 108 return new; 109 } 110 111 void * 112 kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags) 113 { 114 int retries = 0; 115 gfp_t lflags = kmem_flags_convert(flags); 116 void *ptr; 117 118 do { 119 ptr = kmem_cache_alloc(zone, lflags); 120 if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) 121 return ptr; 122 if (!(++retries % 100)) 123 xfs_err(NULL, 124 "%s(%u) possible memory allocation deadlock in %s (mode:0x%x)", 125 current->comm, current->pid, 126 __func__, lflags); 127 congestion_wait(BLK_RW_ASYNC, HZ/50); 128 } while (1); 129 } 130