1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 4 * All Rights Reserved. 5 */ 6 #ifndef __XFS_SUPPORT_KMEM_H__ 7 #define __XFS_SUPPORT_KMEM_H__ 8 9 #include <linux/slab.h> 10 #include <linux/sched.h> 11 #include <linux/mm.h> 12 #include <linux/vmalloc.h> 13 14 /* 15 * General memory allocation interfaces 16 */ 17 18 typedef unsigned __bitwise xfs_km_flags_t; 19 #define KM_NOFS ((__force xfs_km_flags_t)0x0004u) 20 #define KM_MAYFAIL ((__force xfs_km_flags_t)0x0008u) 21 #define KM_ZERO ((__force xfs_km_flags_t)0x0010u) 22 #define KM_NOLOCKDEP ((__force xfs_km_flags_t)0x0020u) 23 24 /* 25 * We use a special process flag to avoid recursive callbacks into 26 * the filesystem during transactions. We will also issue our own 27 * warnings, so we explicitly skip any generic ones (silly of us). 28 */ 29 static inline gfp_t 30 kmem_flags_convert(xfs_km_flags_t flags) 31 { 32 gfp_t lflags; 33 34 BUG_ON(flags & ~(KM_NOFS | KM_MAYFAIL | KM_ZERO | KM_NOLOCKDEP)); 35 36 lflags = GFP_KERNEL | __GFP_NOWARN; 37 if (flags & KM_NOFS) 38 lflags &= ~__GFP_FS; 39 40 /* 41 * Default page/slab allocator behavior is to retry for ever 42 * for small allocations. We can override this behavior by using 43 * __GFP_RETRY_MAYFAIL which will tell the allocator to retry as long 44 * as it is feasible but rather fail than retry forever for all 45 * request sizes. 46 */ 47 if (flags & KM_MAYFAIL) 48 lflags |= __GFP_RETRY_MAYFAIL; 49 50 if (flags & KM_ZERO) 51 lflags |= __GFP_ZERO; 52 53 if (flags & KM_NOLOCKDEP) 54 lflags |= __GFP_NOLOCKDEP; 55 56 return lflags; 57 } 58 59 extern void *kmem_alloc(size_t, xfs_km_flags_t); 60 static inline void kmem_free(const void *ptr) 61 { 62 kvfree(ptr); 63 } 64 65 66 static inline void * 67 kmem_zalloc(size_t size, xfs_km_flags_t flags) 68 { 69 return kmem_alloc(size, flags | KM_ZERO); 70 } 71 72 /* 73 * Zone interfaces 74 */ 75 76 #define kmem_zone kmem_cache 77 #define kmem_zone_t struct kmem_cache 78 79 static inline struct page * 80 kmem_to_page(void *addr) 81 { 82 if (is_vmalloc_addr(addr)) 83 return vmalloc_to_page(addr); 84 return virt_to_page(addr); 85 } 86 87 #endif /* __XFS_SUPPORT_KMEM_H__ */ 88