scsi: lpfc: Refactor and clean up mailbox command memory free

A lot of repeated clean up code exists when freeing mailbox commands in
lpfc_mem_free_all().

Introduce a lpfc_mem_free_sli_mbox() helper routine to refactor the
copy-paste code.  Additionally, reinitialize the mailbox command structure
context pointers to NULL in lpfc_sli4_mbox_cmd_free().

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20231031191224.150862-7-justintee8345@gmail.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: Justin Tee

drivers/scsi/lpfc/lpfc_mbox.c

@@ -1814,7 +1814,9 @@ lpfc_sli4_mbox_cmd_free(struct lpfc_hba *phba, struct lpfcMboxq *mbox)
 		dma_free_coherent(&phba->pcidev->dev, SLI4_PAGE_SIZE,
 				  mbox->sge_array->addr[sgentry], phyaddr);
 	}
-	/* Free the sge address array memory */
+	/* Reinitialize the context pointers to avoid stale usage. */
+	mbox->ctx_buf = NULL;
+	mbox->context3 = NULL;
 	kfree(mbox->sge_array);
 	/* Finally, free the mailbox command itself */
 	mempool_free(mbox, phba->mbox_mem_pool);

drivers/scsi/lpfc/lpfc_mem.c

@@ -48,6 +48,29 @@
 #define LPFC_RRQ_POOL_SIZE	256	/* max elements in non-DMA  pool */
 #define LPFC_MBX_POOL_SIZE	256	/* max elements in MBX non-DMA pool */
 
+/* lpfc_mbox_free_sli_mbox
+ *
+ * @phba: HBA to free memory for
+ * @mbox: mailbox command to free
+ *
+ * This routine detects the mbox type and calls the correct
+ * free routine to fully release all associated memory.
+ */
+static void
+lpfc_mem_free_sli_mbox(struct lpfc_hba *phba, LPFC_MBOXQ_t *mbox)
+{
+	/* Detect if the caller's mbox is an SLI4_CONFIG type.  If so, this
+	 * mailbox type requires a different cleanup routine.  Otherwise, the
+	 * mailbox is just an mbuf and mem_pool release.
+	 */
+	if (phba->sli_rev == LPFC_SLI_REV4 &&
+	    bf_get(lpfc_mqe_command, &mbox->u.mqe) == MBX_SLI4_CONFIG) {
+		lpfc_sli4_mbox_cmd_free(phba, mbox);
+	} else {
+		lpfc_mbox_rsrc_cleanup(phba, mbox, MBOX_THD_UNLOCKED);
+	}
+}
+
 int
 lpfc_mem_alloc_active_rrq_pool_s4(struct lpfc_hba *phba) {
 	size_t bytes;
@@ -288,40 +311,24 @@ lpfc_mem_free_all(struct lpfc_hba *phba)
 {
 	struct lpfc_sli *psli = &phba->sli;
 	LPFC_MBOXQ_t *mbox, *next_mbox;
-	struct lpfc_dmabuf   *mp;
 
 	/* Free memory used in mailbox queue back to mailbox memory pool */
 	list_for_each_entry_safe(mbox, next_mbox, &psli->mboxq, list) {
-		mp = (struct lpfc_dmabuf *)(mbox->ctx_buf);
-		if (mp) {
-			lpfc_mbuf_free(phba, mp->virt, mp->phys);
-			kfree(mp);
-		}
 		list_del(&mbox->list);
-		mempool_free(mbox, phba->mbox_mem_pool);
+		lpfc_mem_free_sli_mbox(phba, mbox);
 	}
 	/* Free memory used in mailbox cmpl list back to mailbox memory pool */
 	list_for_each_entry_safe(mbox, next_mbox, &psli->mboxq_cmpl, list) {
-		mp = (struct lpfc_dmabuf *)(mbox->ctx_buf);
-		if (mp) {
-			lpfc_mbuf_free(phba, mp->virt, mp->phys);
-			kfree(mp);
-		}
 		list_del(&mbox->list);
-		mempool_free(mbox, phba->mbox_mem_pool);
+		lpfc_mem_free_sli_mbox(phba, mbox);
 	}
 	/* Free the active mailbox command back to the mailbox memory pool */
 	spin_lock_irq(&phba->hbalock);
 	psli->sli_flag &= ~LPFC_SLI_MBOX_ACTIVE;
 	spin_unlock_irq(&phba->hbalock);
 	if (psli->mbox_active) {
 		mbox = psli->mbox_active;
-		mp = (struct lpfc_dmabuf *)(mbox->ctx_buf);
-		if (mp) {
-			lpfc_mbuf_free(phba, mp->virt, mp->phys);
-			kfree(mp);
-		}
-		mempool_free(mbox, phba->mbox_mem_pool);
+		lpfc_mem_free_sli_mbox(phba, mbox);
 		psli->mbox_active = NULL;
 	}
 

drivers/scsi/lpfc/lpfc_sli.c

@@ -22170,6 +22170,12 @@ struct lpfc_io_buf *lpfc_get_io_buf(struct lpfc_hba *phba,
  * The data will be truncated if datasz is not large enough.
  * Version 1 is not supported with Embedded mbox cmd, so we must use version 0.
  * Returns the actual bytes read from the object.
+ *
+ * This routine is hard coded to use a poll completion.  Unlike other
+ * sli4_config mailboxes, it uses lpfc_mbuf memory which is not
+ * cleaned up in lpfc_sli4_cmd_mbox_free.  If this routine is modified
+ * to use interrupt-based completions, code is needed to fully cleanup
+ * the memory.
  */
 int
 lpfc_read_object(struct lpfc_hba *phba, char *rdobject, uint32_t *datap,

drivers/scsi/lpfc/lpfc_sli.h

@@ -182,9 +182,11 @@ typedef struct lpfcMboxq {
 		struct lpfc_mqe mqe;
 	} u;
 	struct lpfc_vport *vport; /* virtual port pointer */
-	void *ctx_ndlp;		  /* caller ndlp information */
-	void *ctx_buf;		  /* caller buffer information */
-	void *context3;
+	void *ctx_ndlp;		  /* an lpfc_nodelist pointer */
+	void *ctx_buf;		  /* an lpfc_dmabuf pointer */
+	void *context3;           /* a generic pointer.  Code must
+				   * accommodate the actual datatype.
+				   */
 
 	void (*mbox_cmpl) (struct lpfc_hba *, struct lpfcMboxq *);
 	uint8_t mbox_flag;