cxl: Add psl9 specific code

[mirror_ubuntu-zesty-kernel.git] / drivers / misc / cxl / context.c

diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c
index 3907387b6d1564c5ffc7a7fbcc17a6402d1aaf68..1832c29f0ad85c1f47f3c79d9b741b19adbf2ffe 100644 (file)
--- a/drivers/misc/cxl/context.c
+++ b/drivers/misc/cxl/context.c
@@ -17,6 +17,7 @@
 #include <linux/debugfs.h>
 #include <linux/slab.h>
 #include <linux/idr.h>
+#include <linux/mm.h>
 #include <asm/cputable.h>
 #include <asm/current.h>
 #include <asm/copro.h>
@@ -38,23 +39,26 @@ int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master)
 {
        int i;
 
-       spin_lock_init(&ctx->sste_lock);
        ctx->afu = afu;
        ctx->master = master;
-       ctx->pid = ctx->glpid = NULL; /* Set in start work ioctl */
+       ctx->pid = NULL; /* Set in start work ioctl */
        mutex_init(&ctx->mapping_lock);
        ctx->mapping = NULL;
 
-       /*
-        * Allocate the segment table before we put it in the IDR so that we
-        * can always access it when dereferenced from IDR. For the same
-        * reason, the segment table is only destroyed after the context is
-        * removed from the IDR.  Access to this in the IOCTL is protected by
-        * Linux filesytem symantics (can't IOCTL until open is complete).
-        */
-       i = cxl_alloc_sst(ctx);
-       if (i)
-               return i;
+       if (cxl_is_psl8(afu)) {
+               spin_lock_init(&ctx->sste_lock);
+
+               /*
+                * Allocate the segment table before we put it in the IDR so that we
+                * can always access it when dereferenced from IDR. For the same
+                * reason, the segment table is only destroyed after the context is
+                * removed from the IDR.  Access to this in the IOCTL is protected by
+                * Linux filesytem symantics (can't IOCTL until open is complete).
+                */
+               i = cxl_alloc_sst(ctx);
+               if (i)
+                       return i;
+       }
 
        INIT_WORK(&ctx->fault_work, cxl_handle_fault);
 
@@ -183,13 +187,26 @@ int cxl_context_iomap(struct cxl_context *ctx, struct vm_area_struct *vma)
        if (ctx->afu->current_mode == CXL_MODE_DEDICATED) {
                if (start + len > ctx->afu->adapter->ps_size)
                        return -EINVAL;
+
+               if (cxl_is_psl9(ctx->afu)) {
+                       /*
+                        * Make sure there is a valid problem state
+                        * area space for this AFU.
+                        */
+                       if (ctx->master && !ctx->afu->psa) {
+                               pr_devel("AFU doesn't support mmio space\n");
+                               return -EINVAL;
+                       }
+
+                       /* Can't mmap until the AFU is enabled */
+                       if (!ctx->afu->enabled)
+                               return -EBUSY;
+               }
        } else {
                if (start + len > ctx->psn_size)
                        return -EINVAL;
-       }
 
-       if (ctx->afu->current_mode != CXL_MODE_DEDICATED) {
-               /* make sure there is a valid per process space for this AFU */
+               /* Make sure there is a valid per process space for this AFU */
                if ((ctx->master && !ctx->afu->psa) || (!ctx->afu->pp_psa)) {
                        pr_devel("AFU doesn't support mmio space\n");
                        return -EINVAL;
@@ -241,12 +258,16 @@ int __detach_context(struct cxl_context *ctx)
 
        /* release the reference to the group leader and mm handling pid */
        put_pid(ctx->pid);
-       put_pid(ctx->glpid);
 
        cxl_ctx_put();
 
        /* Decrease the attached context count on the adapter */
        cxl_adapter_context_put(ctx->afu->adapter);
+
+       /* Decrease the mm count on the context */
+       cxl_context_mm_count_put(ctx);
+       ctx->mm = NULL;
+
        return 0;
 }
 
@@ -302,7 +323,8 @@ static void reclaim_ctx(struct rcu_head *rcu)
 {
        struct cxl_context *ctx = container_of(rcu, struct cxl_context, rcu);
 
-       free_page((u64)ctx->sstp);
+       if (cxl_is_psl8(ctx->afu))
+               free_page((u64)ctx->sstp);
        if (ctx->ff_page)
                __free_page(ctx->ff_page);
        ctx->sstp = NULL;
@@ -324,3 +346,15 @@ void cxl_context_free(struct cxl_context *ctx)
        mutex_unlock(&ctx->afu->contexts_lock);
        call_rcu(&ctx->rcu, reclaim_ctx);
 }
+
+void cxl_context_mm_count_get(struct cxl_context *ctx)
+{
+       if (ctx->mm)
+               atomic_inc(&ctx->mm->mm_count);
+}
+
+void cxl_context_mm_count_put(struct cxl_context *ctx)
+{
+       if (ctx->mm)
+               mmdrop(ctx->mm);
+}