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 #ifdef __FreeBSD__
  41 #include <dev/sym/sym_glue.h>
  42 #else
  43 #include "sym_glue.h"
  44 #endif
  45
  46 /*
  47  *  Simple power of two buddy-like generic allocator.
  48  *  Provides naturally aligned memory chunks.
  49  *
  50  *  This simple code is not intended to be fast, but to
  51  *  provide power of 2 aligned memory allocations.
  52  *  Since the SCRIPTS processor only supplies 8 bit arithmetic,
  53  *  this allocator allows simple and fast address calculations
  54  *  from the SCRIPTS code. In addition, cache line alignment
  55  *  is guaranteed for power of 2 cache line size.
  56  *
  57  *  This allocator has been developped for the Linux sym53c8xx
  58  *  driver, since this O/S does not provide naturally aligned
  59  *  allocations.
  60  *  It has the advantage of allowing the driver to use private
  61  *  pages of memory that will be useful if we ever need to deal
  62  *  with IO MMUs for PCI.
  63  */
  64 static void *___sym_malloc(m_pool_p mp, int size)
  65 {
  66         int i = 0;
  67         int s = (1 << SYM_MEM_SHIFT);
  68         int j;
  69         void *a;
  70         m_link_p h = mp->h;
  71
  72         if (size > SYM_MEM_CLUSTER_SIZE)
  73                 return NULL;
  74
  75         while (size > s) {
  76                 s <<= 1;
  77                 ++i;
  78         }
  79
  80         j = i;
  81         while (!h[j].next) {
  82                 if (s == SYM_MEM_CLUSTER_SIZE) {
  83                         h[j].next = (m_link_p) M_GET_MEM_CLUSTER();
  84                         if (h[j].next)
  85                                 h[j].next->next = NULL;
  86                         break;
  87                 }
  88                 ++j;
  89                 s <<= 1;
  90         }
  91         a = h[j].next;
  92         if (a) {
  93                 h[j].next = h[j].next->next;
  94                 while (j > i) {
  95                         j -= 1;
  96                         s >>= 1;
  97                         h[j].next = (m_link_p) (a+s);
  98                         h[j].next->next = NULL;
  99                 }
 100         }
 101 #ifdef DEBUG
 102         printf("___sym_malloc(%d) = %p\n", size, (void *) a);
 103 #endif
 104         return a;
 105 }
 106
 107 /*
 108  *  Counter-part of the generic allocator.
 109  */
 110 static void ___sym_mfree(m_pool_p mp, void *ptr, int size)
 111 {
 112         int i = 0;
 113         int s = (1 << SYM_MEM_SHIFT);
 114         m_link_p q;
 115         unsigned long a, b;
 116         m_link_p h = mp->h;
 117
 118 #ifdef DEBUG
 119         printf("___sym_mfree(%p, %d)\n", ptr, size);
 120 #endif
 121
 122         if (size > SYM_MEM_CLUSTER_SIZE)
 123                 return;
 124
 125         while (size > s) {
 126                 s <<= 1;
 127                 ++i;
 128         }
 129
 130         a = (unsigned long)ptr;
 131
 132         while (1) {
 133                 if (s == SYM_MEM_CLUSTER_SIZE) {
 134 #ifdef SYM_MEM_FREE_UNUSED
 135                         M_FREE_MEM_CLUSTER((void *)a);
 136 #else
 137                         ((m_link_p) a)->next = h[i].next;
 138                         h[i].next = (m_link_p) a;
 139 #endif
 140                         break;
 141                 }
 142                 b = a ^ s;
 143                 q = &h[i];
 144                 while (q->next && q->next != (m_link_p) b) {
 145                         q = q->next;
 146                 }
 147                 if (!q->next) {
 148                         ((m_link_p) a)->next = h[i].next;
 149                         h[i].next = (m_link_p) a;
 150                         break;
 151                 }
 152                 q->next = q->next->next;
 153                 a = a & b;
 154                 s <<= 1;
 155                 ++i;
 156         }
 157 }
 158
 159 /*
 160  *  Verbose and zeroing allocator that wrapps to the generic allocator.
 161  */
 162 static void *__sym_calloc2(m_pool_p mp, int size, char *name, int uflags)
 163 {
 164         void *p;
 165
 166         p = ___sym_malloc(mp, size);
 167
 168         if (DEBUG_FLAGS & DEBUG_ALLOC) {
 169                 printf ("new %-10s[%4d] @%p.\n", name, size, p);
 170         }
 171
 172         if (p)
 173                 memset(p, 0, size);
 174         else if (uflags & SYM_MEM_WARN)
 175                 printf ("__sym_calloc2: failed to allocate %s[%d]\n", name, size);
 176         return p;
 177 }
 178 #define __sym_calloc(mp, s, n)  __sym_calloc2(mp, s, n, SYM_MEM_WARN)
 179
 180 /*
 181  *  Its counter-part.
 182  */
 183 static void __sym_mfree(m_pool_p mp, void *ptr, int size, char *name)
 184 {
 185         if (DEBUG_FLAGS & DEBUG_ALLOC)
 186                 printf ("freeing %-10s[%4d] @%p.\n", name, size, ptr);
 187
 188         ___sym_mfree(mp, ptr, size);
 189 }
 190
 191 /*
 192  *  Default memory pool we donnot need to involve in DMA.
 193  *
 194  *  With DMA abstraction, we use functions (methods), to
 195  *  distinguish between non DMAable memory and DMAable memory.
 196  */
 197 static void *___mp0_get_mem_cluster(m_pool_p mp)
 198 {
 199         void *m = sym_get_mem_cluster();
 200         if (m)
 201                 ++mp->nump;
 202         return m;
 203 }
 204
 205 #ifdef  SYM_MEM_FREE_UNUSED
 206 static void ___mp0_free_mem_cluster(m_pool_p mp, void *m)
 207 {
 208         sym_free_mem_cluster(m);
 209         --mp->nump;
 210 }
 211 #else
 212 #define ___mp0_free_mem_cluster NULL
 213 #endif
 214
 215 static struct sym_m_pool mp0 = {
 216         NULL,
 217         ___mp0_get_mem_cluster,
 218         ___mp0_free_mem_cluster
 219 };
 220
 221 /*
 222  *  Methods that maintains DMAable pools according to user allocations.
 223  *  New pools are created on the fly when a new pool id is provided.
 224  *  They are deleted on the fly when they get emptied.
 225  */
 226 /* Get a memory cluster that matches the DMA constraints of a given pool */
 227 static void * ___get_dma_mem_cluster(m_pool_p mp)
 228 {
 229         m_vtob_p vbp;
 230         void *vaddr;
 231
 232         vbp = __sym_calloc(&mp0, sizeof(*vbp), "VTOB");
 233         if (!vbp)
 234                 goto out_err;
 235
 236         vaddr = sym_m_get_dma_mem_cluster(mp, vbp);
 237         if (vaddr) {
 238                 int hc = VTOB_HASH_CODE(vaddr);
 239                 vbp->next = mp->vtob[hc];
 240                 mp->vtob[hc] = vbp;
 241                 ++mp->nump;
 242         }
 243         return vaddr;
 244 out_err:
 245         return NULL;
 246 }
 247
 248 #ifdef  SYM_MEM_FREE_UNUSED
 249 /* Free a memory cluster and associated resources for DMA */
 250 static void ___free_dma_mem_cluster(m_pool_p mp, void *m)
 251 {
 252         m_vtob_p *vbpp, vbp;
 253         int hc = VTOB_HASH_CODE(m);
 254
 255         vbpp = &mp->vtob[hc];
 256         while (*vbpp && (*vbpp)->vaddr != m)
 257                 vbpp = &(*vbpp)->next;
 258         if (*vbpp) {
 259                 vbp = *vbpp;
 260                 *vbpp = (*vbpp)->next;
 261                 sym_m_free_dma_mem_cluster(mp, vbp);
 262                 __sym_mfree(&mp0, vbp, sizeof(*vbp), "VTOB");
 263                 --mp->nump;
 264         }
 265 }
 266 #endif
 267
 268 /* Fetch the memory pool for a given pool id (i.e. DMA constraints) */
 269 static __inline m_pool_p ___get_dma_pool(m_pool_ident_t dev_dmat)
 270 {
 271         m_pool_p mp;
 272         for (mp = mp0.next;
 273                 mp && !sym_m_pool_match(mp->dev_dmat, dev_dmat);
 274                         mp = mp->next);
 275         return mp;
 276 }
 277
 278 /* Create a new memory DMAable pool (when fetch failed) */
 279 static m_pool_p ___cre_dma_pool(m_pool_ident_t dev_dmat)
 280 {
 281         m_pool_p mp = __sym_calloc(&mp0, sizeof(*mp), "MPOOL");
 282         if (mp) {
 283                 mp->dev_dmat = dev_dmat;
 284                 mp->get_mem_cluster = ___get_dma_mem_cluster;
 285 #ifdef  SYM_MEM_FREE_UNUSED
 286                 mp->free_mem_cluster = ___free_dma_mem_cluster;
 287 #endif
 288                 mp->next = mp0.next;
 289                 mp0.next = mp;
 290                 return mp;
 291         }
 292         return NULL;
 293 }
 294
 295 #ifdef  SYM_MEM_FREE_UNUSED
 296 /* Destroy a DMAable memory pool (when got emptied) */
 297 static void ___del_dma_pool(m_pool_p p)
 298 {
 299         m_pool_p *pp = &mp0.next;
 300
 301         while (*pp && *pp != p)
 302                 pp = &(*pp)->next;
 303         if (*pp) {
 304                 *pp = (*pp)->next;
 305                 __sym_mfree(&mp0, p, sizeof(*p), "MPOOL");
 306         }
 307 }
 308 #endif
 309
 310 /* This lock protects only the memory allocation/free.  */
 311 static DEFINE_SPINLOCK(sym53c8xx_lock);
 312
 313 /*
 314  *  Actual allocator for DMAable memory.
 315  */
 316 void *__sym_calloc_dma(m_pool_ident_t dev_dmat, int size, char *name)
 317 {
 318         unsigned long flags;
 319         m_pool_p mp;
 320         void *m = NULL;
 321
 322         spin_lock_irqsave(&sym53c8xx_lock, flags);
 323         mp = ___get_dma_pool(dev_dmat);
 324         if (!mp)
 325                 mp = ___cre_dma_pool(dev_dmat);
 326         if (!mp)
 327                 goto out;
 328         m = __sym_calloc(mp, size, name);
 329 #ifdef  SYM_MEM_FREE_UNUSED
 330         if (!mp->nump)
 331                 ___del_dma_pool(mp);
 332 #endif
 333
 334  out:
 335         spin_unlock_irqrestore(&sym53c8xx_lock, flags);
 336         return m;
 337 }
 338
 339 void __sym_mfree_dma(m_pool_ident_t dev_dmat, void *m, int size, char *name)
 340 {
 341         unsigned long flags;
 342         m_pool_p mp;
 343
 344         spin_lock_irqsave(&sym53c8xx_lock, flags);
 345         mp = ___get_dma_pool(dev_dmat);
 346         if (!mp)
 347                 goto out;
 348         __sym_mfree(mp, m, size, name);
 349 #ifdef  SYM_MEM_FREE_UNUSED
 350         if (!mp->nump)
 351                 ___del_dma_pool(mp);
 352 #endif
 353  out:
 354         spin_unlock_irqrestore(&sym53c8xx_lock, flags);
 355 }
 356
 357 /*
 358  *  Actual virtual to bus physical address translator
 359  *  for 32 bit addressable DMAable memory.
 360  */
 361 dma_addr_t __vtobus(m_pool_ident_t dev_dmat, void *m)
 362 {
 363         unsigned long flags;
 364         m_pool_p mp;
 365         int hc = VTOB_HASH_CODE(m);
 366         m_vtob_p vp = NULL;
 367         void *a = (void *)((unsigned long)m & ~SYM_MEM_CLUSTER_MASK);
 368         dma_addr_t b;
 369
 370         spin_lock_irqsave(&sym53c8xx_lock, flags);
 371         mp = ___get_dma_pool(dev_dmat);
 372         if (mp) {
 373                 vp = mp->vtob[hc];
 374                 while (vp && vp->vaddr != a)
 375                         vp = vp->next;
 376         }
 377         if (!vp)
 378                 panic("sym: VTOBUS FAILED!\n");
 379         b = vp->baddr + (m - a);
 380         spin_unlock_irqrestore(&sym53c8xx_lock, flags);
 381         return b;
 382 }