[PATCH v5 2/8] hw/sd/sd: Add buffer argument to sd_blk_{read,write}

[Bernhard Beschow]

The next patch offers to skip the s->data bounce buffer for CMD18 and
CMD25. Prepare for that by adding a buffer parameter.

Rather than introducing two new wrapper functions, as in the inspiring
commit, the additional argument is added at all call sites. This reduces
the number of helper functions and matches existing code where multiple
sd->* arguments are passed to sd_blk_{read,write}.

This patch is inspired by: 
https://lore.kernel.org/qemu-devel/20260417-sdcard-performance-b4-v4-3-119e66be1...@avm.de/

Inspired-by: Christian Speich <c.spe...@avm.de>
Signed-off-by: Bernhard Beschow <shen...@gmail.com>
---
 hw/sd/sd.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/hw/sd/sd.c b/hw/sd/sd.c
index 759db66e3d..bccb839ce6 100644
--- a/hw/sd/sd.c
+++ b/hw/sd/sd.c
@@ -1113,20 +1113,22 @@ static const VMStateDescription sd_vmstate = {
     },
 };
 
-static void sd_blk_read(SDState *sd, uint64_t addr, uint32_t len)
+static void sd_blk_read(SDState *sd, void* buf, uint64_t addr,
+                        uint32_t len)
 {
     trace_sdcard_read_block(addr, len);
     addr += sd_part_offset(sd);
-    if (!sd->blk || blk_pread(sd->blk, addr, len, sd->data, 0) < 0) {
+    if (!sd->blk || blk_pread(sd->blk, addr, len, buf, 0) < 0) {
         fprintf(stderr, "sd_blk_read: read error on host side\n");
     }
 }
 
-static void sd_blk_write(SDState *sd, uint64_t addr, uint32_t len)
+static void sd_blk_write(SDState *sd, const void *buf, uint64_t addr,
+                         uint32_t len)
 {
     trace_sdcard_write_block(addr, len);
     addr += sd_part_offset(sd);
-    if (!sd->blk || blk_pwrite(sd->blk, addr, len, sd->data, 0) < 0) {
+    if (!sd->blk || blk_pwrite(sd->blk, addr, len, buf, 0) < 0) {
         fprintf(stderr, "sd_blk_write: write error on host side\n");
     }
 }
@@ -1364,7 +1366,7 @@ static void sd_erase(SDState *sd)
                 continue;
             }
         }
-        sd_blk_write(sd, erase_addr, erase_len);
+        sd_blk_write(sd, sd->data, erase_addr, erase_len);
     }
 }
 
@@ -1985,7 +1987,7 @@ static sd_rsp_type_t sd_cmd_READ_SINGLE_BLOCK(SDState 
*sd, SDRequest req)
         return sd_r1;
     }
 
-    sd_blk_read(sd, addr, sd->blk_len);
+    sd_blk_read(sd, sd->data, addr, sd->blk_len);
     return sd_cmd_to_sendingdata(sd, req, addr, NULL, sd->blk_len);
 }
 
@@ -2685,7 +2687,7 @@ static size_t sd_write_data(SDState *sd, const void *buf, 
size_t length)
         if (sd_generic_write_data(sd, buf, &length)) {
             /* TODO: Check CRC before committing */
             sd->state = sd_programming_state;
-            sd_blk_write(sd, sd->data_start, sd->data_offset);
+            sd_blk_write(sd, sd->data, sd->data_start, sd->data_offset);
             sd->blk_written ++;
             sd->csd[14] |= 0x40;
             /* Bzzzzzzztt .... Operation complete.  */
@@ -2720,7 +2722,7 @@ static size_t sd_write_data(SDState *sd, const void *buf, 
size_t length)
             if (partition_access == EXT_CSD_PART_CONFIG_ACC_RPMB) {
                 emmc_rpmb_blk_write(sd, sd->data_start, sd->data_offset);
             } else {
-                sd_blk_write(sd, sd->data_start, sd->data_offset);
+                sd_blk_write(sd, sd->data, sd->data_start, sd->data_offset);
             }
             sd->blk_written++;
             sd->data_start += sd->blk_len;
@@ -2858,7 +2860,7 @@ static size_t sd_read_data(SDState *sd, void *buf, size_t 
length)
             if (partition_access == EXT_CSD_PART_CONFIG_ACC_RPMB) {
                 emmc_rpmb_blk_read(sd, sd->data_start, io_len);
             } else {
-                sd_blk_read(sd, sd->data_start, io_len);
+                sd_blk_read(sd, sd->data, sd->data_start, io_len);
             }
         }
 
-- 
2.56.0