include/sys/kmem.h

   1 /*****************************************************************************\
   2  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
   3  *  Copyright (C) 2007 The Regents of the University of California.
   4  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
   5  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
   6  *  UCRL-CODE-235197
   7  *
   8  *  This file is part of the SPL, Solaris Porting Layer.
   9  *  For details, see <http://github.com/behlendorf/spl/>.
  10  *
  11  *  The SPL is free software; you can redistribute it and/or modify it
  12  *  under the terms of the GNU General Public License as published by the
  13  *  Free Software Foundation; either version 2 of the License, or (at your
  14  *  option) any later version.
  15  *
  16  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
  17  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19  *  for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
  23 \*****************************************************************************/
  24
  25 #ifndef _SPL_KMEM_H
  26 #define _SPL_KMEM_H
  27
  28 #undef DEBUG_KMEM_UNIMPLEMENTED
  29
  30 #include <linux/module.h>
  31 #include <linux/slab.h>
  32 #include <linux/vmalloc.h>
  33 #include <linux/mm_compat.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/rwsem.h>
  36 #include <linux/hash.h>
  37 #include <linux/ctype.h>
  38 #include <asm/atomic.h>
  39 #include <sys/types.h>
  40 #include <sys/debug.h>
  41 #include <sys/vmsystm.h>
  42
  43 /*
  44  * Memory allocation interfaces
  45  */
  46 #define KM_SLEEP                        GFP_KERNEL
  47 #define KM_NOSLEEP                      GFP_ATOMIC
  48 #undef  KM_PANIC                        /* No linux analog */
  49 #define KM_PUSHPAGE                     (KM_SLEEP | __GFP_HIGH)
  50 #define KM_VMFLAGS                      GFP_LEVEL_MASK
  51 #define KM_FLAGS                        __GFP_BITS_MASK
  52
  53 /*
  54  * Used internally, the kernel does not need to support this flag
  55  */
  56 #ifndef __GFP_ZERO
  57 # define __GFP_ZERO                     0x8000
  58 #endif
  59
  60 /*
  61  * __GFP_NOFAIL looks like it will be removed from the kernel perhaps as
  62  * early as 2.6.32.  To avoid this issue when it occurs in upstream kernels
  63  * we retry the allocation here as long as it is not __GFP_WAIT (GFP_ATOMIC).
  64  * I would prefer the caller handle the failure case cleanly but we are
  65  * trying to emulate Solaris and those are not the Solaris semantics.
  66  */
  67 static inline void *
  68 kmalloc_nofail(size_t size, gfp_t flags)
  69 {
  70         void *ptr;
  71
  72         do {
  73                 ptr = kmalloc(size, flags);
  74         } while (ptr == NULL && (flags & __GFP_WAIT));
  75
  76         return ptr;
  77 }
  78
  79 static inline void *
  80 kzalloc_nofail(size_t size, gfp_t flags)
  81 {
  82         void *ptr;
  83
  84         do {
  85                 ptr = kzalloc(size, flags);
  86         } while (ptr == NULL && (flags & __GFP_WAIT));
  87
  88         return ptr;
  89 }
  90
  91 #ifdef HAVE_KMALLOC_NODE
  92 static inline void *
  93 kmalloc_node_nofail(size_t size, gfp_t flags, int node)
  94 {
  95         void *ptr;
  96
  97         do {
  98                 ptr = kmalloc_node(size, flags, node);
  99         } while (ptr == NULL && (flags & __GFP_WAIT));
 100
 101         return ptr;
 102 }
 103 #endif /* HAVE_KMALLOC_NODE */
 104
 105 #ifdef DEBUG_KMEM
 106 # ifdef HAVE_ATOMIC64_T
 107
 108 extern atomic64_t kmem_alloc_used;
 109 extern unsigned long long kmem_alloc_max;
 110 extern atomic64_t vmem_alloc_used;
 111 extern unsigned long long vmem_alloc_max;
 112
 113 # define kmem_alloc_used_add(size)      atomic64_add(size, &kmem_alloc_used)
 114 # define kmem_alloc_used_sub(size)      atomic64_sub(size, &kmem_alloc_used)
 115 # define kmem_alloc_used_read()         atomic64_read(&kmem_alloc_used)
 116 # define kmem_alloc_used_set(size)      atomic64_set(&kmem_alloc_used, size)
 117 # define vmem_alloc_used_add(size)      atomic64_add(size, &vmem_alloc_used)
 118 # define vmem_alloc_used_sub(size)      atomic64_sub(size, &vmem_alloc_used)
 119 # define vmem_alloc_used_read()         atomic64_read(&vmem_alloc_used)
 120 # define vmem_alloc_used_set(size)      atomic64_set(&vmem_alloc_used, size)
 121
 122 # else
 123
 124 extern atomic_t kmem_alloc_used;
 125 extern unsigned long long kmem_alloc_max;
 126 extern atomic_t vmem_alloc_used;
 127 extern unsigned long long vmem_alloc_max;
 128
 129 # define kmem_alloc_used_add(size)      atomic_add(size, &kmem_alloc_used)
 130 # define kmem_alloc_used_sub(size)      atomic_sub(size, &kmem_alloc_used)
 131 # define kmem_alloc_used_read()         atomic_read(&kmem_alloc_used)
 132 # define kmem_alloc_used_set(size)      atomic_set(&kmem_alloc_used, size)
 133 # define vmem_alloc_used_add(size)      atomic_add(size, &vmem_alloc_used)
 134 # define vmem_alloc_used_sub(size)      atomic_sub(size, &vmem_alloc_used)
 135 # define vmem_alloc_used_read()         atomic_read(&vmem_alloc_used)
 136 # define vmem_alloc_used_set(size)      atomic_set(&vmem_alloc_used, size)
 137
 138 # endif /* _LP64 */
 139
 140 # define kmem_alloc(size, flags)             __kmem_alloc((size), (flags), 0, 0)
 141 # define kmem_zalloc(size, flags)            __kmem_alloc((size), ((flags) |  \
 142                                                  __GFP_ZERO), 0, 0)
 143
 144 /* The node alloc functions are only used by the SPL code itself */
 145 # ifdef HAVE_KMALLOC_NODE
 146 #  define kmem_alloc_node(size, flags, node) __kmem_alloc((size), (flags), 1, \
 147                                                  node)
 148 # else
 149 #  define kmem_alloc_node(size, flags, node) __kmem_alloc((size), (flags), 0, 0)
 150 # endif
 151
 152 # define vmem_zalloc(size, flags)            vmem_alloc((size), ((flags) |    \
 153                                                  __GFP_ZERO))
 154
 155 # ifdef DEBUG_KMEM_TRACKING
 156
 157 extern void *kmem_alloc_track(size_t size, int flags, const char *func,
 158     int line, int node_alloc, int node);
 159 extern void kmem_free_track(void *ptr, size_t size);
 160 extern void *vmem_alloc_track(size_t size, int flags, const char *func,
 161     int line);
 162 extern void vmem_free_track(void *ptr, size_t size);
 163
 164 #  define __kmem_alloc(size, flags, na, node) kmem_alloc_track((size),        \
 165                                                   (flags), __FUNCTION__,      \
 166                                                   __LINE__, (na), (node))
 167 #  define kmem_free(ptr, size)                kmem_free_track((ptr), (size))
 168 #  define vmem_alloc(size, flags)             vmem_alloc_track((size),        \
 169                                                   (flags),__FUNCTION__,       \
 170                                                   __LINE__)
 171 #  define vmem_free(ptr, size)                vmem_free_track((ptr), (size))
 172
 173 # else /* DEBUG_KMEM_TRACKING */
 174
 175 extern void *kmem_alloc_debug(size_t size, int flags, const char *func,
 176     int line, int node_alloc, int node);
 177 extern void kmem_free_debug(void *ptr, size_t size);
 178 extern void *vmem_alloc_debug(size_t size, int flags, const char *func,
 179     int line);
 180 extern void vmem_free_debug(void *ptr, size_t size);
 181
 182 #  define __kmem_alloc(size, flags, na, node) kmem_alloc_debug((size),        \
 183                                                   (flags), __FUNCTION__,      \
 184                                                   __LINE__, (na), (node))
 185 #  define kmem_free(ptr, size)                kmem_free_debug((ptr), (size))
 186 #  define vmem_alloc(size, flags)             vmem_alloc_debug((size),        \
 187                                                   (flags), __FUNCTION__,      \
 188                                                   __LINE__)
 189 #  define vmem_free(ptr, size)                vmem_free_debug((ptr), (size))
 190
 191 # endif /* DEBUG_KMEM_TRACKING */
 192
 193 #else /* DEBUG_KMEM */
 194
 195 # define kmem_alloc(size, flags)              kmalloc_nofail((size), (flags))
 196 # define kmem_zalloc(size, flags)             kzalloc_nofail((size), (flags))
 197 # define kmem_free(ptr, size)                 ((void)(size), kfree(ptr))
 198
 199 # ifdef HAVE_KMALLOC_NODE
 200 #  define kmem_alloc_node(size, flags, node)                                  \
 201           kmalloc_node_nofail((size), (flags), (node))
 202 # else
 203 #  define kmem_alloc_node(size, flags, node)                                  \
 204           kmalloc_nofail((size), (flags))
 205 # endif
 206
 207 # define vmem_alloc(size, flags)              __vmalloc((size), ((flags) |    \
 208                                                   __GFP_HIGHMEM), PAGE_KERNEL)
 209 # define vmem_zalloc(size, flags)                                             \
 210 ({                                                                            \
 211         void *_ptr_ = __vmalloc((size),((flags)|__GFP_HIGHMEM),PAGE_KERNEL);  \
 212         if (_ptr_)                                                            \
 213                 memset(_ptr_, 0, (size));                                     \
 214         _ptr_;                                                                \
 215 })
 216 # define vmem_free(ptr, size)           ((void)(size), vfree(ptr))
 217
 218 #endif /* DEBUG_KMEM */
 219
 220 #ifdef DEBUG_KMEM_UNIMPLEMENTED
 221 static __inline__ void *
 222 kmem_alloc_tryhard(size_t size, size_t *alloc_size, int kmflags)
 223 {
 224 #error "kmem_alloc_tryhard() not implemented"
 225 }
 226 #endif /* DEBUG_KMEM_UNIMPLEMENTED */
 227
 228 /*
 229  * Slab allocation interfaces
 230  */
 231 enum {
 232         KMC_BIT_NOTOUCH         = 0,    /* Don't update ages */
 233         KMC_BIT_NODEBUG         = 1,    /* Default behavior */
 234         KMC_BIT_NOMAGAZINE      = 2,    /* XXX: Unsupported */
 235         KMC_BIT_NOHASH          = 3,    /* XXX: Unsupported */
 236         KMC_BIT_QCACHE          = 4,    /* XXX: Unsupported */
 237         KMC_BIT_KMEM            = 5,    /* Use kmem cache */
 238         KMC_BIT_VMEM            = 6,    /* Use vmem cache */
 239         KMC_BIT_OFFSLAB         = 7,    /* Objects not on slab */
 240         KMC_BIT_REAPING         = 16,   /* Reaping in progress */
 241         KMC_BIT_DESTROY         = 17,   /* Destroy in progress */
 242 };
 243
 244 #define KMC_NOTOUCH             (1 << KMC_BIT_NOTOUCH)
 245 #define KMC_NODEBUG             (1 << KMC_BIT_NODEBUG)
 246 #define KMC_NOMAGAZINE          (1 << KMC_BIT_NOMAGAZINE)
 247 #define KMC_NOHASH              (1 << KMC_BIT_NOHASH)
 248 #define KMC_QCACHE              (1 << KMC_BIT_QCACHE)
 249 #define KMC_KMEM                (1 << KMC_BIT_KMEM)
 250 #define KMC_VMEM                (1 << KMC_BIT_VMEM)
 251 #define KMC_OFFSLAB             (1 << KMC_BIT_OFFSLAB)
 252 #define KMC_REAPING             (1 << KMC_BIT_REAPING)
 253 #define KMC_DESTROY             (1 << KMC_BIT_DESTROY)
 254
 255 #define KMC_REAP_CHUNK                  INT_MAX
 256 #define KMC_DEFAULT_SEEKS               1
 257
 258 #ifdef DEBUG_KMEM_UNIMPLEMENTED
 259 static __inline__ void kmem_init(void) {
 260 #error "kmem_init() not implemented"
 261 }
 262
 263 static __inline__ void kmem_thread_init(void) {
 264 #error "kmem_thread_init() not implemented"
 265 }
 266
 267 static __inline__ void kmem_mp_init(void) {
 268 #error "kmem_mp_init() not implemented"
 269 }
 270
 271 static __inline__ void kmem_reap_idspace(void) {
 272 #error "kmem_reap_idspace() not implemented"
 273 }
 274
 275 static __inline__ size_t kmem_avail(void) {
 276 #error "kmem_avail() not implemented"
 277 }
 278
 279 static __inline__ size_t kmem_maxavail(void) {
 280 #error "kmem_maxavail() not implemented"
 281 }
 282
 283 static __inline__ uint64_t kmem_cache_stat(spl_kmem_cache_t *cache) {
 284 #error "kmem_cache_stat() not implemented"
 285 }
 286 #endif /* DEBUG_KMEM_UNIMPLEMENTED */
 287
 288 /* XXX - Used by arc.c to adjust its memory footprint. We may want
 289  *       to use this hook in the future to adjust behavior based on
 290  *       debug levels.  For now it's safe to always return 0.
 291  */
 292 static __inline__ int
 293 kmem_debugging(void)
 294 {
 295         return 0;
 296 }
 297
 298 extern int kmem_set_warning(int flag);
 299
 300 extern struct list_head spl_kmem_cache_list;
 301 extern struct rw_semaphore spl_kmem_cache_sem;
 302
 303 #define SKM_MAGIC                       0x2e2e2e2e
 304 #define SKO_MAGIC                       0x20202020
 305 #define SKS_MAGIC                       0x22222222
 306 #define SKC_MAGIC                       0x2c2c2c2c
 307
 308 #define SPL_KMEM_CACHE_DELAY            15      /* Minimum slab release age */
 309 #define SPL_KMEM_CACHE_REAP             0       /* Default reap everything */
 310 #define SPL_KMEM_CACHE_OBJ_PER_SLAB     32      /* Target objects per slab */
 311 #define SPL_KMEM_CACHE_OBJ_PER_SLAB_MIN 8       /* Minimum objects per slab */
 312 #define SPL_KMEM_CACHE_ALIGN            8       /* Default object alignment */
 313
 314 typedef int (*spl_kmem_ctor_t)(void *, void *, int);
 315 typedef void (*spl_kmem_dtor_t)(void *, void *);
 316 typedef void (*spl_kmem_reclaim_t)(void *);
 317
 318 typedef struct spl_kmem_magazine {
 319         uint32_t                skm_magic;      /* Sanity magic */
 320         uint32_t                skm_avail;      /* Available objects */
 321         uint32_t                skm_size;       /* Magazine size */
 322         uint32_t                skm_refill;     /* Batch refill size */
 323         struct spl_kmem_cache   *skm_cache;     /* Owned by cache */
 324         struct delayed_work     skm_work;       /* Magazine reclaim work */
 325         unsigned long           skm_age;        /* Last cache access */
 326         void                    *skm_objs[0];   /* Object pointers */
 327 } spl_kmem_magazine_t;
 328
 329 typedef struct spl_kmem_obj {
 330         uint32_t                sko_magic;      /* Sanity magic */
 331         void                    *sko_addr;      /* Buffer address */
 332         struct spl_kmem_slab    *sko_slab;      /* Owned by slab */
 333         struct list_head        sko_list;       /* Free object list linkage */
 334 } spl_kmem_obj_t;
 335
 336 typedef struct spl_kmem_slab {
 337         uint32_t                sks_magic;      /* Sanity magic */
 338         uint32_t                sks_objs;       /* Objects per slab */
 339         struct spl_kmem_cache   *sks_cache;     /* Owned by cache */
 340         struct list_head        sks_list;       /* Slab list linkage */
 341         struct list_head        sks_free_list;  /* Free object list */
 342         unsigned long           sks_age;        /* Last modify jiffie */
 343         uint32_t                sks_ref;        /* Ref count used objects */
 344 } spl_kmem_slab_t;
 345
 346 typedef struct spl_kmem_cache {
 347         uint32_t                skc_magic;      /* Sanity magic */
 348         uint32_t                skc_name_size;  /* Name length */
 349         char                    *skc_name;      /* Name string */
 350         spl_kmem_magazine_t     *skc_mag[NR_CPUS]; /* Per-CPU warm cache */
 351         uint32_t                skc_mag_size;   /* Magazine size */
 352         uint32_t                skc_mag_refill; /* Magazine refill count */
 353         spl_kmem_ctor_t         skc_ctor;       /* Constructor */
 354         spl_kmem_dtor_t         skc_dtor;       /* Destructor */
 355         spl_kmem_reclaim_t      skc_reclaim;    /* Reclaimator */
 356         void                    *skc_private;   /* Private data */
 357         void                    *skc_vmp;       /* Unused */
 358         unsigned long           skc_flags;      /* Flags */
 359         uint32_t                skc_obj_size;   /* Object size */
 360         uint32_t                skc_obj_align;  /* Object alignment */
 361         uint32_t                skc_slab_objs;  /* Objects per slab */
 362         uint32_t                skc_slab_size;  /* Slab size */
 363         uint32_t                skc_delay;      /* Slab reclaim interval */
 364         uint32_t                skc_reap;       /* Slab reclaim count */
 365         atomic_t                skc_ref;        /* Ref count callers */
 366         struct delayed_work     skc_work;       /* Slab reclaim work */
 367         struct list_head        skc_list;       /* List of caches linkage */
 368         struct list_head        skc_complete_list;/* Completely alloc'ed */
 369         struct list_head        skc_partial_list; /* Partially alloc'ed */
 370         spinlock_t              skc_lock;       /* Cache lock */
 371         uint64_t                skc_slab_fail;  /* Slab alloc failures */
 372         uint64_t                skc_slab_create;/* Slab creates */
 373         uint64_t                skc_slab_destroy;/* Slab destroys */
 374         uint64_t                skc_slab_total; /* Slab total current */
 375         uint64_t                skc_slab_alloc; /* Slab alloc current */
 376         uint64_t                skc_slab_max;   /* Slab max historic  */
 377         uint64_t                skc_obj_total;  /* Obj total current */
 378         uint64_t                skc_obj_alloc;  /* Obj alloc current */
 379         uint64_t                skc_obj_max;    /* Obj max historic */
 380 } spl_kmem_cache_t;
 381 #define kmem_cache_t            spl_kmem_cache_t
 382
 383 extern spl_kmem_cache_t *
 384 spl_kmem_cache_create(char *name, size_t size, size_t align,
 385         spl_kmem_ctor_t ctor, spl_kmem_dtor_t dtor, spl_kmem_reclaim_t reclaim,
 386         void *priv, void *vmp, int flags);
 387
 388 extern void spl_kmem_cache_destroy(spl_kmem_cache_t *skc);
 389 extern void *spl_kmem_cache_alloc(spl_kmem_cache_t *skc, int flags);
 390 extern void spl_kmem_cache_free(spl_kmem_cache_t *skc, void *obj);
 391 extern void spl_kmem_cache_reap_now(spl_kmem_cache_t *skc);
 392 extern void spl_kmem_reap(void);
 393
 394 int spl_kmem_init_kallsyms_lookup(void);
 395 int spl_kmem_init(void);
 396 void spl_kmem_fini(void);
 397
 398 #define kmem_cache_create(name,size,align,ctor,dtor,rclm,priv,vmp,flags) \
 399         spl_kmem_cache_create(name,size,align,ctor,dtor,rclm,priv,vmp,flags)
 400 #define kmem_cache_destroy(skc)         spl_kmem_cache_destroy(skc)
 401 #define kmem_cache_alloc(skc, flags)    spl_kmem_cache_alloc(skc, flags)
 402 #define kmem_cache_free(skc, obj)       spl_kmem_cache_free(skc, obj)
 403 #define kmem_cache_reap_now(skc)        spl_kmem_cache_reap_now(skc)
 404 #define kmem_reap()                     spl_kmem_reap()
 405 #define kmem_virt(ptr)                  (((ptr) >= (void *)VMALLOC_START) && \
 406                                          ((ptr) <  (void *)VMALLOC_END))
 407
 408 #endif  /* _SPL_KMEM_H */