[PATCH v5 06/12] dma/cnxk: chunk buffer failure return code

[Amit Prakash Shukla <amitprakashs@marvell.com>]

On chunk buffer alloc failure, ENOMEM is returned. As per DMA spec
ENOSPC shall be returned on failure to allocate memory. This
changeset fixes the same.

Fixes: b56f1e2dad38 ("dma/cnxk: add channel operations")
Cc: stable@dpdk.org

Signed-off-by: Amit Prakash Shukla <amitprakashs@marvell.com>
---
v2:
- Fix for bugs observed in v1.
- Squashed few commits.

v3:
- Resolved review suggestions.
- Code improvement.

v4:
- Resolved checkpatch warnings.

v5:
- Updated commit message.
- Split the commits.

 drivers/dma/cnxk/cnxk_dmadev.c | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/dma/cnxk/cnxk_dmadev.c b/drivers/dma/cnxk/cnxk_dmadev.c
index 0db74b454d..aa6f6c710c 100644
--- a/drivers/dma/cnxk/cnxk_dmadev.c
+++ b/drivers/dma/cnxk/cnxk_dmadev.c
@@ -257,8 +257,7 @@ __dpi_queue_write(struct roc_dpi *dpi, uint64_t *cmds, int cmd_count)
 {
 	uint64_t *ptr = dpi->chunk_base;
 
-	if ((cmd_count < DPI_MIN_CMD_SIZE) || (cmd_count > DPI_MAX_CMD_SIZE) ||
-	    cmds == NULL)
+	if ((cmd_count < DPI_MIN_CMD_SIZE) || (cmd_count > DPI_MAX_CMD_SIZE) || cmds == NULL)
 		return -EINVAL;
 
 	/*
@@ -274,11 +273,15 @@ __dpi_queue_write(struct roc_dpi *dpi, uint64_t *cmds, int cmd_count)
 		int count;
 		uint64_t *new_buff = dpi->chunk_next;
 
-		dpi->chunk_next =
-			(void *)roc_npa_aura_op_alloc(dpi->aura_handle, 0);
+		dpi->chunk_next = (void *)roc_npa_aura_op_alloc(dpi->aura_handle, 0);
 		if (!dpi->chunk_next) {
-			plt_err("Failed to alloc next buffer from NPA");
-			return -ENOMEM;
+			plt_dp_dbg("Failed to alloc next buffer from NPA");
+
+			/* NPA failed to allocate a buffer. Restoring chunk_next
+			 * to its original address.
+			 */
+			dpi->chunk_next = new_buff;
+			return -ENOSPC;
 		}
 
 		/*
@@ -312,13 +315,17 @@ __dpi_queue_write(struct roc_dpi *dpi, uint64_t *cmds, int cmd_count)
 		/* queue index may be greater than pool size */
 		if (dpi->chunk_head >= dpi->pool_size_m1) {
 			new_buff = dpi->chunk_next;
-			dpi->chunk_next =
-				(void *)roc_npa_aura_op_alloc(dpi->aura_handle,
-							      0);
+			dpi->chunk_next = (void *)roc_npa_aura_op_alloc(dpi->aura_handle, 0);
 			if (!dpi->chunk_next) {
-				plt_err("Failed to alloc next buffer from NPA");
-				return -ENOMEM;
+				plt_dp_dbg("Failed to alloc next buffer from NPA");
+
+				/* NPA failed to allocate a buffer. Restoring chunk_next
+				 * to its original address.
+				 */
+				dpi->chunk_next = new_buff;
+				return -ENOSPC;
 			}
+
 			/* Write next buffer address */
 			*ptr = (uint64_t)new_buff;
 			dpi->chunk_base = new_buff;
-- 
2.25.1