/*
* Start a context
* Code here similar to afu_ioctl_start_work().
*/
int cxl_start_context(struct cxl_context *ctx, u64 wed,
struct task_struct *task)
{
int rc = 0;
bool kernel = true;
pr_devel("%s: pe: %i\n", __func__, ctx->pe);
mutex_lock(&ctx->status_mutex);
if (ctx->status == STARTED)
goto out; /* already started */
if (task) {
ctx->pid = get_task_pid(task, PIDTYPE_PID);
get_pid(ctx->pid);
kernel = false;
}
cxl_ctx_get();
if ((rc = cxl_attach_process(ctx, kernel, wed , 0))) {
put_pid(ctx->pid);
cxl_ctx_put();
goto out;
}
ctx->status = STARTED;
out:
mutex_unlock(&ctx->status_mutex);
return rc;
}
static int afu_release(struct inode *inode, struct file *file)
{
struct cxl_context *ctx = file->private_data;
pr_devel("%s: closing cxl file descriptor. pe: %i\n",
__func__, ctx->pe);
cxl_context_detach(ctx);
mutex_lock(&ctx->mapping_lock);
ctx->mapping = NULL;
mutex_unlock(&ctx->mapping_lock);
put_device(&ctx->afu->dev);
/*
* At this this point all bottom halfs have finished and we should be
* getting no more IRQs from the hardware for this context. Once it's
* removed from the IDR (and RCU synchronised) it's safe to free the
* sstp and context.
*/
cxl_context_free(ctx);
cxl_ctx_put();
return 0;
}
/*
* Start a context
* Code here similar to afu_ioctl_start_work().
*/
int cxl_start_context(struct cxl_context *ctx, u64 wed,
struct task_struct *task)
{
int rc = 0;
bool kernel = true;
pr_devel("%s: pe: %i\n", __func__, ctx->pe);
mutex_lock(&ctx->status_mutex);
if (ctx->status == STARTED)
goto out; /* already started */
/*
* Increment the mapped context count for adapter. This also checks
* if adapter_context_lock is taken.
*/
rc = cxl_adapter_context_get(ctx->afu->adapter);
if (rc)
goto out;
if (task) {
ctx->pid = get_task_pid(task, PIDTYPE_PID);
kernel = false;
/* acquire a reference to the task's mm */
ctx->mm = get_task_mm(current);
/* ensure this mm_struct can't be freed */
cxl_context_mm_count_get(ctx);
if (ctx->mm) {
/* decrement the use count from above */
mmput(ctx->mm);
/* make TLBIs for this context global */
mm_context_add_copro(ctx->mm);
}
}
/*
* Increment driver use count. Enables global TLBIs for hash
* and callbacks to handle the segment table
*/
cxl_ctx_get();
/* See the comment in afu_ioctl_start_work() */
smp_mb();
if ((rc = cxl_ops->attach_process(ctx, kernel, wed, 0))) {
put_pid(ctx->pid);
ctx->pid = NULL;
cxl_adapter_context_put(ctx->afu->adapter);
cxl_ctx_put();
if (task) {
cxl_context_mm_count_put(ctx);
if (ctx->mm)
mm_context_remove_copro(ctx->mm);
}
goto out;
}
ctx->status = STARTED;
out:
mutex_unlock(&ctx->status_mutex);
return rc;
}
