scsi: cxlflash: Use IDR to manage adapter contexts

A range of PASIDs are used as identifiers for the adapter contexts. These
contexts may be destroyed and created randomly. Use an IDR to keep track of
contexts that are in use and assign a unique identifier to new ones.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 19 insertions, 2 deletions

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index cbe4d9341f5a..e8864a1f244d 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -12,6 +12,8 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/idr.h>
+
 #include <misc/ocxl.h>
 
 #include "backend.h"
@@ -60,14 +62,25 @@ static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
 	if (unlikely(!ctx)) {
 		dev_err(dev, "%s: Context allocation failed\n", __func__);
 		rc = -ENOMEM;
-		goto err;
+		goto err1;
+	}
+
+	idr_preload(GFP_KERNEL);
+	rc = idr_alloc(&afu->idr, ctx, 0, afu->max_pasid, GFP_NOWAIT);
+	idr_preload_end();
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: idr_alloc failed rc=%d\n", __func__, rc);
+		goto err2;
 	}
 
+	ctx->pe = rc;
 	ctx->master = false;
 	ctx->hw_afu = afu;
 out:
 	return ctx;
-err:
+err2:
+	kfree(ctx);
+err1:
 	ctx = ERR_PTR(rc);
 	goto out;
 }
@@ -86,6 +99,7 @@ static int ocxlflash_release_context(void *ctx_cookie)
 	if (!ctx)
 		goto out;
 
+	idr_remove(&ctx->hw_afu->idr, ctx->pe);
 	kfree(ctx);
 out:
 	return rc;
@@ -103,6 +117,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 		return;
 
 	ocxlflash_release_context(afu->ocxl_ctx);
+	idr_destroy(&afu->idr);
 	kfree(afu);
 }
 
@@ -221,6 +236,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 
 	afu->pdev = pdev;
 	afu->dev = dev;
+	idr_init(&afu->idr);
 
 	rc = ocxlflash_config_fn(pdev, afu);
 	if (unlikely(rc)) {
@@ -248,6 +264,7 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 out:
 	return afu;
 err1:
+	idr_destroy(&afu->idr);
 	kfree(afu);
 	afu = NULL;
 	goto out;