arch/powerpc/platforms/cell/spufs/context.c

   1 /*
   2  * SPU file system -- SPU context management
   3  *
   4  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
   5  *
   6  * Author: Arnd Bergmann <arndb@de.ibm.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #include <linux/fs.h>
  24 #include <linux/mm.h>
  25 #include <linux/module.h>
  26 #include <linux/slab.h>
  27 #include <asm/atomic.h>
  28 #include <asm/spu.h>
  29 #include <asm/spu_csa.h>
  30 #include "spufs.h"
  31
  32
  33 atomic_t nr_spu_contexts = ATOMIC_INIT(0);
  34
  35 struct spu_context *alloc_spu_context(struct spu_gang *gang)
  36 {
  37         struct spu_context *ctx;
  38         ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
  39         if (!ctx)
  40                 goto out;
  41         /* Binding to physical processor deferred
  42          * until spu_activate().
  43          */
  44         if (spu_init_csa(&ctx->csa))
  45                 goto out_free;
  46         spin_lock_init(&ctx->mmio_lock);
  47         mutex_init(&ctx->mapping_lock);
  48         kref_init(&ctx->kref);
  49         mutex_init(&ctx->state_mutex);
  50         mutex_init(&ctx->run_mutex);
  51         init_waitqueue_head(&ctx->ibox_wq);
  52         init_waitqueue_head(&ctx->wbox_wq);
  53         init_waitqueue_head(&ctx->stop_wq);
  54         init_waitqueue_head(&ctx->mfc_wq);
  55         ctx->state = SPU_STATE_SAVED;
  56         ctx->ops = &spu_backing_ops;
  57         ctx->owner = get_task_mm(current);
  58         INIT_LIST_HEAD(&ctx->rq);
  59         INIT_LIST_HEAD(&ctx->aff_list);
  60         if (gang)
  61                 spu_gang_add_ctx(gang, ctx);
  62         ctx->cpus_allowed = current->cpus_allowed;
  63         spu_set_timeslice(ctx);
  64         ctx->stats.util_state = SPU_UTIL_IDLE_LOADED;
  65
  66         atomic_inc(&nr_spu_contexts);
  67         goto out;
  68 out_free:
  69         kfree(ctx);
  70         ctx = NULL;
  71 out:
  72         return ctx;
  73 }
  74
  75 void destroy_spu_context(struct kref *kref)
  76 {
  77         struct spu_context *ctx;
  78         ctx = container_of(kref, struct spu_context, kref);
  79         mutex_lock(&ctx->state_mutex);
  80         spu_deactivate(ctx);
  81         mutex_unlock(&ctx->state_mutex);
  82         spu_fini_csa(&ctx->csa);
  83         if (ctx->gang)
  84                 spu_gang_remove_ctx(ctx->gang, ctx);
  85         if (ctx->prof_priv_kref)
  86                 kref_put(ctx->prof_priv_kref, ctx->prof_priv_release);
  87         BUG_ON(!list_empty(&ctx->rq));
  88         atomic_dec(&nr_spu_contexts);
  89         kfree(ctx);
  90 }
  91
  92 struct spu_context * get_spu_context(struct spu_context *ctx)
  93 {
  94         kref_get(&ctx->kref);
  95         return ctx;
  96 }
  97
  98 int put_spu_context(struct spu_context *ctx)
  99 {
 100         return kref_put(&ctx->kref, &destroy_spu_context);
 101 }
 102
 103 /* give up the mm reference when the context is about to be destroyed */
 104 void spu_forget(struct spu_context *ctx)
 105 {
 106         struct mm_struct *mm;
 107         spu_acquire_saved(ctx);
 108         mm = ctx->owner;
 109         ctx->owner = NULL;
 110         mmput(mm);
 111         spu_release(ctx);
 112 }
 113
 114 void spu_unmap_mappings(struct spu_context *ctx)
 115 {
 116         mutex_lock(&ctx->mapping_lock);
 117         if (ctx->local_store)
 118                 unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
 119         if (ctx->mfc)
 120                 unmap_mapping_range(ctx->mfc, 0, 0x1000, 1);
 121         if (ctx->cntl)
 122                 unmap_mapping_range(ctx->cntl, 0, 0x1000, 1);
 123         if (ctx->signal1)
 124                 unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1);
 125         if (ctx->signal2)
 126                 unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1);
 127         if (ctx->mss)
 128                 unmap_mapping_range(ctx->mss, 0, 0x1000, 1);
 129         if (ctx->psmap)
 130                 unmap_mapping_range(ctx->psmap, 0, 0x20000, 1);
 131         mutex_unlock(&ctx->mapping_lock);
 132 }
 133
 134 /**
 135  * spu_acquire_runnable - lock spu contex and make sure it is in runnable state
 136  * @ctx:        spu contex to lock
 137  *
 138  * Note:
 139  *      Returns 0 and with the context locked on success
 140  *      Returns negative error and with the context _unlocked_ on failure.
 141  */
 142 int spu_acquire_runnable(struct spu_context *ctx, unsigned long flags)
 143 {
 144         int ret = -EINVAL;
 145
 146         spu_acquire(ctx);
 147         if (ctx->state == SPU_STATE_SAVED) {
 148                 /*
 149                  * Context is about to be freed, so we can't acquire it anymore.
 150                  */
 151                 if (!ctx->owner)
 152                         goto out_unlock;
 153                 ret = spu_activate(ctx, flags);
 154                 if (ret)
 155                         goto out_unlock;
 156         }
 157
 158         return 0;
 159
 160  out_unlock:
 161         spu_release(ctx);
 162         return ret;
 163 }
 164
 165 /**
 166  * spu_acquire_saved - lock spu contex and make sure it is in saved state
 167  * @ctx:        spu contex to lock
 168  */
 169 void spu_acquire_saved(struct spu_context *ctx)
 170 {
 171         spu_acquire(ctx);
 172         if (ctx->state != SPU_STATE_SAVED) {
 173                 set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
 174                 spu_deactivate(ctx);
 175         }
 176 }
 177
 178 /**
 179  * spu_release_saved - unlock spu context and return it to the runqueue
 180  * @ctx:        context to unlock
 181  */
 182 void spu_release_saved(struct spu_context *ctx)
 183 {
 184         BUG_ON(ctx->state != SPU_STATE_SAVED);
 185
 186         if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags))
 187                 spu_activate(ctx, 0);
 188
 189         spu_release(ctx);
 190 }
 191
 192 void spu_set_profile_private_kref(struct spu_context *ctx,
 193                                   struct kref *prof_info_kref,
 194                                   void ( * prof_info_release) (struct kref *kref))
 195 {
 196         ctx->prof_priv_kref = prof_info_kref;
 197         ctx->prof_priv_release = prof_info_release;
 198 }
 199 EXPORT_SYMBOL_GPL(spu_set_profile_private_kref);
 200
 201 void *spu_get_profile_private_kref(struct spu_context *ctx)
 202 {
 203         return ctx->prof_priv_kref;
 204 }
 205 EXPORT_SYMBOL_GPL(spu_get_profile_private_kref);
 206
 207