drivers/scsi/sym53c8xx_2/sym_malloc.c

   1 /*
   2  * Device driver for the SYMBIOS/LSILOGIC 53C8XX and 53C1010 family
   3  * of PCI-SCSI IO processors.
   4  *
   5  * Copyright (C) 1999-2001  Gerard Roudier <groudier@free.fr>
   6  *
   7  * This driver is derived from the Linux sym53c8xx driver.
   8  * Copyright (C) 1998-2000  Gerard Roudier
   9  *
  10  * The sym53c8xx driver is derived from the ncr53c8xx driver that had been
  11  * a port of the FreeBSD ncr driver to Linux-1.2.13.
  12  *
  13  * The original ncr driver has been written for 386bsd and FreeBSD by
  14  *         Wolfgang Stanglmeier        <wolf@cologne.de>
  15  *         Stefan Esser                <se@mi.Uni-Koeln.de>
  16  * Copyright (C) 1994  Wolfgang Stanglmeier
  17  *
  18  * Other major contributions:
  19  *
  20  * NVRAM detection and reading.
  21  * Copyright (C) 1997 Richard Waltham <dormouse@farsrobt.demon.co.uk>
  22  *
  23  *-----------------------------------------------------------------------------
  24  *
  25  * This program is free software; you can redistribute it and/or modify
  26  * it under the terms of the GNU General Public License as published by
  27  * the Free Software Foundation; either version 2 of the License, or
  28  * (at your option) any later version.
  29  *
  30  * This program is distributed in the hope that it will be useful,
  31  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  32  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  33  * GNU General Public License for more details.
  34  *
  35  * You should have received a copy of the GNU General Public License
  36  * along with this program; if not, write to the Free Software
  37  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  38  */
  39
  40 #include "sym_glue.h"
  41
  42 /*
  43  *  Simple power of two buddy-like generic allocator.
  44  *  Provides naturally aligned memory chunks.
  45  *
  46  *  This simple code is not intended to be fast, but to
  47  *  provide power of 2 aligned memory allocations.
  48  *  Since the SCRIPTS processor only supplies 8 bit arithmetic,
  49  *  this allocator allows simple and fast address calculations
  50  *  from the SCRIPTS code. In addition, cache line alignment
  51  *  is guaranteed for power of 2 cache line size.
  52  *
  53  *  This allocator has been developed for the Linux sym53c8xx
  54  *  driver, since this O/S does not provide naturally aligned
  55  *  allocations.
  56  *  It has the advantage of allowing the driver to use private
  57  *  pages of memory that will be useful if we ever need to deal
  58  *  with IO MMUs for PCI.
  59  */
  60 static void *___sym_malloc(m_pool_p mp, int size)
  61 {
  62         int i = 0;
  63         int s = (1 << SYM_MEM_SHIFT);
  64         int j;
  65         void *a;
  66         m_link_p h = mp->h;
  67
  68         if (size > SYM_MEM_CLUSTER_SIZE)
  69                 return NULL;
  70
  71         while (size > s) {
  72                 s <<= 1;
  73                 ++i;
  74         }
  75
  76         j = i;
  77         while (!h[j].next) {
  78                 if (s == SYM_MEM_CLUSTER_SIZE) {
  79                         h[j].next = (m_link_p) M_GET_MEM_CLUSTER();
  80                         if (h[j].next)
  81                                 h[j].next->next = NULL;
  82                         break;
  83                 }
  84                 ++j;
  85                 s <<= 1;
  86         }
  87         a = h[j].next;
  88         if (a) {
  89                 h[j].next = h[j].next->next;
  90                 while (j > i) {
  91                         j -= 1;
  92                         s >>= 1;
  93                         h[j].next = (m_link_p) (a+s);
  94                         h[j].next->next = NULL;
  95                 }
  96         }
  97 #ifdef DEBUG
  98         printf("___sym_malloc(%d) = %p\n", size, (void *) a);
  99 #endif
 100         return a;
 101 }
 102
 103 /*
 104  *  Counter-part of the generic allocator.
 105  */
 106 static void ___sym_mfree(m_pool_p mp, void *ptr, int size)
 107 {
 108         int i = 0;
 109         int s = (1 << SYM_MEM_SHIFT);
 110         m_link_p q;
 111         unsigned long a, b;
 112         m_link_p h = mp->h;
 113
 114 #ifdef DEBUG
 115         printf("___sym_mfree(%p, %d)\n", ptr, size);
 116 #endif
 117
 118         if (size > SYM_MEM_CLUSTER_SIZE)
 119                 return;
 120
 121         while (size > s) {
 122                 s <<= 1;
 123                 ++i;
 124         }
 125
 126         a = (unsigned long)ptr;
 127
 128         while (1) {
 129                 if (s == SYM_MEM_CLUSTER_SIZE) {
 130 #ifdef SYM_MEM_FREE_UNUSED
 131                         M_FREE_MEM_CLUSTER((void *)a);
 132 #else
 133                         ((m_link_p) a)->next = h[i].next;
 134                         h[i].next = (m_link_p) a;
 135 #endif
 136                         break;
 137                 }
 138                 b = a ^ s;
 139                 q = &h[i];
 140                 while (q->next && q->next != (m_link_p) b) {
 141                         q = q->next;
 142                 }
 143                 if (!q->next) {
 144                         ((m_link_p) a)->next = h[i].next;
 145                         h[i].next = (m_link_p) a;
 146                         break;
 147                 }
 148                 q->next = q->next->next;
 149                 a = a & b;
 150                 s <<= 1;
 151                 ++i;
 152         }
 153 }
 154
 155 /*
 156  *  Verbose and zeroing allocator that wrapps to the generic allocator.
 157  */
 158 static void *__sym_calloc2(m_pool_p mp, int size, char *name, int uflags)
 159 {
 160         void *p;
 161
 162         p = ___sym_malloc(mp, size);
 163
 164         if (DEBUG_FLAGS & DEBUG_ALLOC) {
 165                 printf ("new %-10s[%4d] @%p.\n", name, size, p);
 166         }
 167
 168         if (p)
 169                 memset(p, 0, size);
 170         else if (uflags & SYM_MEM_WARN)
 171                 printf ("__sym_calloc2: failed to allocate %s[%d]\n", name, size);
 172         return p;
 173 }
 174 #define __sym_calloc(mp, s, n)  __sym_calloc2(mp, s, n, SYM_MEM_WARN)
 175
 176 /*
 177  *  Its counter-part.
 178  */
 179 static void __sym_mfree(m_pool_p mp, void *ptr, int size, char *name)
 180 {
 181         if (DEBUG_FLAGS & DEBUG_ALLOC)
 182                 printf ("freeing %-10s[%4d] @%p.\n", name, size, ptr);
 183
 184         ___sym_mfree(mp, ptr, size);
 185 }
 186
 187 /*
 188  *  Default memory pool we donnot need to involve in DMA.
 189  *
 190  *  With DMA abstraction, we use functions (methods), to
 191  *  distinguish between non DMAable memory and DMAable memory.
 192  */
 193 static void *___mp0_get_mem_cluster(m_pool_p mp)
 194 {
 195         void *m = sym_get_mem_cluster();
 196         if (m)
 197                 ++mp->nump;
 198         return m;
 199 }
 200
 201 #ifdef  SYM_MEM_FREE_UNUSED
 202 static void ___mp0_free_mem_cluster(m_pool_p mp, void *m)
 203 {
 204         sym_free_mem_cluster(m);
 205         --mp->nump;
 206 }
 207 #else
 208 #define ___mp0_free_mem_cluster NULL
 209 #endif
 210
 211 static struct sym_m_pool mp0 = {
 212         NULL,
 213         ___mp0_get_mem_cluster,
 214         ___mp0_free_mem_cluster
 215 };
 216
 217 /*
 218  *  Methods that maintains DMAable pools according to user allocations.
 219  *  New pools are created on the fly when a new pool id is provided.
 220  *  They are deleted on the fly when they get emptied.
 221  */
 222 /* Get a memory cluster that matches the DMA constraints of a given pool */
 223 static void * ___get_dma_mem_cluster(m_pool_p mp)
 224 {
 225         m_vtob_p vbp;
 226         void *vaddr;
 227
 228         vbp = __sym_calloc(&mp0, sizeof(*vbp), "VTOB");
 229         if (!vbp)
 230                 goto out_err;
 231
 232         vaddr = sym_m_get_dma_mem_cluster(mp, vbp);
 233         if (vaddr) {
 234                 int hc = VTOB_HASH_CODE(vaddr);
 235                 vbp->next = mp->vtob[hc];
 236                 mp->vtob[hc] = vbp;
 237                 ++mp->nump;
 238         }
 239         return vaddr;
 240 out_err:
 241         return NULL;
 242 }
 243
 244 #ifdef  SYM_MEM_FREE_UNUSED
 245 /* Free a memory cluster and associated resources for DMA */
 246 static void ___free_dma_mem_cluster(m_pool_p mp, void *m)
 247 {
 248         m_vtob_p *vbpp, vbp;
 249         int hc = VTOB_HASH_CODE(m);
 250
 251         vbpp = &mp->vtob[hc];
 252         while (*vbpp && (*vbpp)->vaddr != m)
 253                 vbpp = &(*vbpp)->next;
 254         if (*vbpp) {
 255                 vbp = *vbpp;
 256                 *vbpp = (*vbpp)->next;
 257                 sym_m_free_dma_mem_cluster(mp, vbp);
 258                 __sym_mfree(&mp0, vbp, sizeof(*vbp), "VTOB");
 259                 --mp->nump;
 260         }
 261 }
 262 #endif
 263
 264 /* Fetch the memory pool for a given pool id (i.e. DMA constraints) */
 265 static inline m_pool_p ___get_dma_pool(m_pool_ident_t dev_dmat)
 266 {
 267         m_pool_p mp;
 268         for (mp = mp0.next;
 269                 mp && !sym_m_pool_match(mp->dev_dmat, dev_dmat);
 270                         mp = mp->next);
 271         return mp;
 272 }
 273
 274 /* Create a new memory DMAable pool (when fetch failed) */
 275 static m_pool_p ___cre_dma_pool(m_pool_ident_t dev_dmat)
 276 {
 277         m_pool_p mp = __sym_calloc(&mp0, sizeof(*mp), "MPOOL");
 278         if (mp) {
 279                 mp->dev_dmat = dev_dmat;
 280                 mp->get_mem_cluster = ___get_dma_mem_cluster;
 281 #ifdef  SYM_MEM_FREE_UNUSED
 282                 mp->free_mem_cluster = ___free_dma_mem_cluster;
 283 #endif
 284                 mp->next = mp0.next;
 285                 mp0.next = mp;
 286                 return mp;
 287         }
 288         return NULL;
 289 }
 290
 291 #ifdef  SYM_MEM_FREE_UNUSED
 292 /* Destroy a DMAable memory pool (when got emptied) */
 293 static void ___del_dma_pool(m_pool_p p)
 294 {
 295         m_pool_p *pp = &mp0.next;
 296
 297         while (*pp && *pp != p)
 298                 pp = &(*pp)->next;
 299         if (*pp) {
 300                 *pp = (*pp)->next;
 301                 __sym_mfree(&mp0, p, sizeof(*p), "MPOOL");
 302         }
 303 }
 304 #endif
 305
 306 /* This lock protects only the memory allocation/free.  */
 307 static DEFINE_SPINLOCK(sym53c8xx_lock);
 308
 309 /*
 310  *  Actual allocator for DMAable memory.
 311  */
 312 void *__sym_calloc_dma(m_pool_ident_t dev_dmat, int size, char *name)
 313 {
 314         unsigned long flags;
 315         m_pool_p mp;
 316         void *m = NULL;
 317
 318         spin_lock_irqsave(&sym53c8xx_lock, flags);
 319         mp = ___get_dma_pool(dev_dmat);
 320         if (!mp)
 321                 mp = ___cre_dma_pool(dev_dmat);
 322         if (!mp)
 323                 goto out;
 324         m = __sym_calloc(mp, size, name);
 325 #ifdef  SYM_MEM_FREE_UNUSED
 326         if (!mp->nump)
 327                 ___del_dma_pool(mp);
 328 #endif
 329
 330  out:
 331         spin_unlock_irqrestore(&sym53c8xx_lock, flags);
 332         return m;
 333 }
 334
 335 void __sym_mfree_dma(m_pool_ident_t dev_dmat, void *m, int size, char *name)
 336 {
 337         unsigned long flags;
 338         m_pool_p mp;
 339
 340         spin_lock_irqsave(&sym53c8xx_lock, flags);
 341         mp = ___get_dma_pool(dev_dmat);
 342         if (!mp)
 343                 goto out;
 344         __sym_mfree(mp, m, size, name);
 345 #ifdef  SYM_MEM_FREE_UNUSED
 346         if (!mp->nump)
 347                 ___del_dma_pool(mp);
 348 #endif
 349  out:
 350         spin_unlock_irqrestore(&sym53c8xx_lock, flags);
 351 }
 352
 353 /*
 354  *  Actual virtual to bus physical address translator
 355  *  for 32 bit addressable DMAable memory.
 356  */
 357 dma_addr_t __vtobus(m_pool_ident_t dev_dmat, void *m)
 358 {
 359         unsigned long flags;
 360         m_pool_p mp;
 361         int hc = VTOB_HASH_CODE(m);
 362         m_vtob_p vp = NULL;
 363         void *a = (void *)((unsigned long)m & ~SYM_MEM_CLUSTER_MASK);
 364         dma_addr_t b;
 365
 366         spin_lock_irqsave(&sym53c8xx_lock, flags);
 367         mp = ___get_dma_pool(dev_dmat);
 368         if (mp) {
 369                 vp = mp->vtob[hc];
 370                 while (vp && vp->vaddr != a)
 371                         vp = vp->next;
 372         }
 373         if (!vp)
 374                 panic("sym: VTOBUS FAILED!\n");
 375         b = vp->baddr + (m - a);
 376         spin_unlock_irqrestore(&sym53c8xx_lock, flags);
 377         return b;
 378 }