Merge branch 'cxgb4-reduce-memory-footprint-for-collecting-firmware-d…

…ump'

Rahul Lakkireddy says:

====================
cxgb4: reduce memory footprint for collecting firmware dump

Firmware dump can be large (upto 2 GB).  In low memory conditions,
ethtool fails to allocate such large memory.  So, use zlib deflate
to compress collected firmware dump.

Patch 1 updates collection logic to use compression.

Patch 2 adds zlib deflate to compress collected firmware dump.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/Makefile

@@ -12,3 +12,4 @@ cxgb4-objs := cxgb4_main.o l2t.o smt.o t4_hw.o sge.o clip_tbl.o cxgb4_ethtool.o
 cxgb4-$(CONFIG_CHELSIO_T4_DCB) +=  cxgb4_dcb.o
 cxgb4-$(CONFIG_CHELSIO_T4_FCOE) +=  cxgb4_fcoe.o
 cxgb4-$(CONFIG_DEBUG_FS) += cxgb4_debugfs.o
+cxgb4-$(CONFIG_ZLIB_DEFLATE) += cudbg_zlib.o

drivers/net/ethernet/chelsio/cxgb4/cudbg_common.c

@@ -19,7 +19,8 @@
 #include "cudbg_if.h"
 #include "cudbg_lib_common.h"
 
-int cudbg_get_buff(struct cudbg_buffer *pdbg_buff, u32 size,
+int cudbg_get_buff(struct cudbg_init *pdbg_init,
+		   struct cudbg_buffer *pdbg_buff, u32 size,
 		   struct cudbg_buffer *pin_buff)
 {
 	u32 offset;
@@ -28,17 +29,30 @@ int cudbg_get_buff(struct cudbg_buffer *pdbg_buff, u32 size,
 	if (offset + size > pdbg_buff->size)
 		return CUDBG_STATUS_NO_MEM;
 
+	if (pdbg_init->compress_type != CUDBG_COMPRESSION_NONE) {
+		if (size > pdbg_init->compress_buff_size)
+			return CUDBG_STATUS_NO_MEM;
+
+		pin_buff->data = (char *)pdbg_init->compress_buff;
+		pin_buff->offset = 0;
+		pin_buff->size = size;
+		return 0;
+	}
+
 	pin_buff->data = (char *)pdbg_buff->data + offset;
 	pin_buff->offset = offset;
 	pin_buff->size = size;
-	pdbg_buff->size -= size;
 	return 0;
 }
 
-void cudbg_put_buff(struct cudbg_buffer *pin_buff,
-		    struct cudbg_buffer *pdbg_buff)
+void cudbg_put_buff(struct cudbg_init *pdbg_init,
+		    struct cudbg_buffer *pin_buff)
 {
-	pdbg_buff->size += pin_buff->size;
+	/* Clear compression buffer for re-use */
+	if (pdbg_init->compress_type != CUDBG_COMPRESSION_NONE)
+		memset(pdbg_init->compress_buff, 0,
+		       pdbg_init->compress_buff_size);
+
 	pin_buff->data = NULL;
 	pin_buff->offset = 0;
 	pin_buff->size = 0;

drivers/net/ethernet/chelsio/cxgb4/cudbg_if.h

@@ -87,6 +87,10 @@ struct cudbg_init {
 	struct adapter *adap; /* Pointer to adapter structure */
 	void *outbuf; /* Output buffer */
 	u32 outbuf_size;  /* Output buffer size */
+	u8 compress_type; /* Type of compression to use */
+	void *compress_buff; /* Compression buffer */
+	u32 compress_buff_size; /* Compression buffer size */
+	void *workspace; /* Workspace for zlib */
 };
 
 static inline unsigned int cudbg_mbytes_to_bytes(unsigned int size)