| 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 | } |