kern: ahci: Correct buffer order during ahci r/w

Move to the buffer given to us if there it is a read, move from the
buffer given to us if it is a write

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 17 insertions, 6 deletions

diff --git a/src/sys/io/ic/ahci.c b/src/sys/io/ic/ahci.c
index 682c983..e6137e8 100644
--- a/src/sys/io/ic/ahci.c
+++ b/src/sys/io/ic/ahci.c
@@ -281,6 +281,7 @@ ahci_rw(struct ahci_hba *hba, struct ahci_port *port, struct bufargs *bufd)
     struct ahci_cmdtab *cmdtbl;
     struct ahci_fis_h2d *fis;
     paddr_t buf, cmdbase;
+    void *va;
     int cmdslot, status;
     size_t npgs;
 
@@ -304,6 +305,11 @@ ahci_rw(struct ahci_hba *hba, struct ahci_port *port, struct bufargs *bufd)
         return -ENOMEM;
     }
 
+    if (bufd->write) {
+        va = PHYS_TO_VIRT(buf);
+        memcpy(va, bufd->buf, bufd->nblocks * 512);
+    }
+
     /* Get the command list entry for this slot */
     cmdslot = ahci_alloc_cmdslot(hba, port);
     cmdbase = port->cmdlist;
@@ -342,12 +348,17 @@ ahci_rw(struct ahci_hba *hba, struct ahci_port *port, struct bufargs *bufd)
         return status;
     }
 
-    /* Now copy it to the real buffer */
-    memcpy(
-        bufd->buf,
-        PHYS_TO_VIRT(buf),
-        bufd->nblocks * 512
-    );
+    /*
+     * Now copy it to the real buffer if
+     * reading
+     */
+    if (!bufd->write) {
+        memcpy(
+            bufd->buf,
+            PHYS_TO_VIRT(buf),
+            bufd->nblocks * 512
+        );
+    }
 
     vm_free_frame(buf, npgs);
     return 0;