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 init_waitqueue_head(&ctx->run_wq); 56 ctx->state = SPU_STATE_SAVED; 57 ctx->ops = &spu_backing_ops; 58 ctx->owner = get_task_mm(current); 59 INIT_LIST_HEAD(&ctx->rq); 60 INIT_LIST_HEAD(&ctx->aff_list); 61 if (gang) 62 spu_gang_add_ctx(gang, ctx); 63 64 __spu_update_sched_info(ctx); 65 spu_set_timeslice(ctx); 66 ctx->stats.util_state = SPU_UTIL_IDLE_LOADED; 67 68 atomic_inc(&nr_spu_contexts); 69 goto out; 70 out_free: 71 kfree(ctx); 72 ctx = NULL; 73 out: 74 return ctx; 75 } 76 77 void destroy_spu_context(struct kref *kref) 78 { 79 struct spu_context *ctx; 80 ctx = container_of(kref, struct spu_context, kref); 81 mutex_lock(&ctx->state_mutex); 82 spu_deactivate(ctx); 83 mutex_unlock(&ctx->state_mutex); 84 spu_fini_csa(&ctx->csa); 85 if (ctx->gang) 86 spu_gang_remove_ctx(ctx->gang, ctx); 87 if (ctx->prof_priv_kref) 88 kref_put(ctx->prof_priv_kref, ctx->prof_priv_release); 89 BUG_ON(!list_empty(&ctx->rq)); 90 atomic_dec(&nr_spu_contexts); 91 kfree(ctx); 92 } 93 94 struct spu_context * get_spu_context(struct spu_context *ctx) 95 { 96 kref_get(&ctx->kref); 97 return ctx; 98 } 99 100 int put_spu_context(struct spu_context *ctx) 101 { 102 return kref_put(&ctx->kref, &destroy_spu_context); 103 } 104 105 /* give up the mm reference when the context is about to be destroyed */ 106 void spu_forget(struct spu_context *ctx) 107 { 108 struct mm_struct *mm; 109 110 /* 111 * This is basically an open-coded spu_acquire_saved, except that 112 * we don't acquire the state mutex interruptible, and we don't 113 * want this context to be rescheduled on release. 114 */ 115 mutex_lock(&ctx->state_mutex); 116 if (ctx->state != SPU_STATE_SAVED) 117 spu_deactivate(ctx); 118 119 mm = ctx->owner; 120 ctx->owner = NULL; 121 mmput(mm); 122 spu_release(ctx); 123 } 124 125 void spu_unmap_mappings(struct spu_context *ctx) 126 { 127 mutex_lock(&ctx->mapping_lock); 128 if (ctx->local_store) 129 unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1); 130 if (ctx->mfc) 131 unmap_mapping_range(ctx->mfc, 0, 0x1000, 1); 132 if (ctx->cntl) 133 unmap_mapping_range(ctx->cntl, 0, 0x1000, 1); 134 if (ctx->signal1) 135 unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1); 136 if (ctx->signal2) 137 unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1); 138 if (ctx->mss) 139 unmap_mapping_range(ctx->mss, 0, 0x1000, 1); 140 if (ctx->psmap) 141 unmap_mapping_range(ctx->psmap, 0, 0x20000, 1); 142 mutex_unlock(&ctx->mapping_lock); 143 } 144 145 /** 146 * spu_acquire_saved - lock spu contex and make sure it is in saved state 147 * @ctx: spu contex to lock 148 */ 149 int spu_acquire_saved(struct spu_context *ctx) 150 { 151 int ret; 152 153 ret = spu_acquire(ctx); 154 if (ret) 155 return ret; 156 157 if (ctx->state != SPU_STATE_SAVED) { 158 set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags); 159 spu_deactivate(ctx); 160 } 161 162 return 0; 163 } 164 165 /** 166 * spu_release_saved - unlock spu context and return it to the runqueue 167 * @ctx: context to unlock 168 */ 169 void spu_release_saved(struct spu_context *ctx) 170 { 171 BUG_ON(ctx->state != SPU_STATE_SAVED); 172 173 if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags) && 174 test_bit(SPU_SCHED_SPU_RUN, &ctx->sched_flags)) 175 spu_activate(ctx, 0); 176 177 spu_release(ctx); 178 } 179 180