From cc774926f12eff377bc25ed571e69b7978c1d978 Mon Sep 17 00:00:00 2001
From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Mon, 30 Jan 2012 12:26:11 +0100
Subject: [PATCH] 	SCSI write support (for usbms mainly).

	* grub-core/disk/scsi.c (grub_scsi_write10): Uncomment. Make buffer
	a const pointer.
	(grub_scsi_write): Implement.
	* include/grub/scsi.h (grub_scsi_dev): Make write buffer a const pointer
---
 ChangeLog              |  9 +++++++++
 grub-core/disk/ata.c   |  2 +-
 grub-core/disk/scsi.c  | 42 ++++++++++++++++++++++++++++++++++--------
 grub-core/disk/usbms.c |  4 ++--
 include/grub/scsi.h    |  2 +-
 5 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1055d1ad4..5641803dc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2012-01-30  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	SCSI write support (for usbms mainly).
+
+	* grub-core/disk/scsi.c (grub_scsi_write10): Uncomment. Make buffer
+	a const pointer.
+	(grub_scsi_write): Implement.
+	* include/grub/scsi.h (grub_scsi_dev): Make write buffer a const pointer
+
 2012-01-30  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/io/lzopio.c (uncompress_block): Fix use of incorrect
diff --git a/grub-core/disk/ata.c b/grub-core/disk/ata.c
index 6d2ec0c78..c90e86832 100644
--- a/grub-core/disk/ata.c
+++ b/grub-core/disk/ata.c
@@ -537,7 +537,7 @@ grub_atapi_write (struct grub_scsi *scsi __attribute__((unused)),
 		  grub_size_t cmdsize __attribute__((unused)),
 		  char *cmd __attribute__((unused)),
 		  grub_size_t size __attribute__((unused)),
-		  char *buf __attribute__((unused)))
+		  const char *buf __attribute__((unused)))
 {
   // XXX: scsi.mod does not use write yet.
   return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "ATAPI write not implemented");
diff --git a/grub-core/disk/scsi.c b/grub-core/disk/scsi.c
index 610cc4dc5..b22f651e9 100644
--- a/grub-core/disk/scsi.c
+++ b/grub-core/disk/scsi.c
@@ -253,12 +253,11 @@ grub_scsi_read12 (grub_disk_t disk, grub_disk_addr_t sector,
   return err;
 }
 
-#if 0
 /* Send a SCSI request for DISK: write the data stored in BUF to SIZE
    sectors starting with SECTOR.  */
 static grub_err_t
 grub_scsi_write10 (grub_disk_t disk, grub_disk_addr_t sector,
-		   grub_size_t size, char *buf)
+		   grub_size_t size, const char *buf)
 {
   grub_scsi_t scsi;
   struct grub_scsi_write10 wr;
@@ -287,6 +286,8 @@ grub_scsi_write10 (grub_disk_t disk, grub_disk_addr_t sector,
   return err;
 }
 
+#if 0
+
 /* Send a SCSI request for DISK: write the data stored in BUF to SIZE
    sectors starting with SECTOR.  */
 static grub_err_t
@@ -595,13 +596,38 @@ grub_scsi_write (grub_disk_t disk __attribute((unused)),
 		 grub_size_t size __attribute((unused)),
 		 const char *buf __attribute((unused)))
 {
-#if 0
-  /* XXX: Not tested yet!  */
+  grub_scsi_t scsi;
 
-  /* XXX: This should depend on the device type?  */
-  return grub_scsi_write10 (disk, sector, size, buf);
-#endif
-  return GRUB_ERR_NOT_IMPLEMENTED_YET;
+  scsi = disk->data;
+
+  if (scsi->devtype == grub_scsi_devtype_cdrom)
+    return grub_error (GRUB_ERR_IO, "no CD burning");
+
+  while (size)
+    {
+      /* PATA doesn't support more than 32K reads.
+	 Not sure about AHCI and USB. If it's confirmed that either of
+	 them can do bigger reads reliably this value can be moved to 'scsi'
+	 structure.  */
+      grub_size_t len = 32768 >> disk->log_sector_size;
+      grub_err_t err;
+      if (len > size)
+	len = size;
+      /* Depending on the type, select a read function.  */
+      switch (scsi->devtype)
+	{
+	case grub_scsi_devtype_direct:
+	  err = grub_scsi_write10 (disk, sector, len, buf);
+	  if (err)
+	    return err;
+	  break;
+	}
+      size -= len;
+      sector += len;
+      buf += len << disk->log_sector_size;
+    }
+
+  return GRUB_ERR_NONE;
 }
 
 
diff --git a/grub-core/disk/usbms.c b/grub-core/disk/usbms.c
index a4c2addf1..e264c464c 100644
--- a/grub-core/disk/usbms.c
+++ b/grub-core/disk/usbms.c
@@ -388,9 +388,9 @@ grub_usbms_read (struct grub_scsi *scsi, grub_size_t cmdsize, char *cmd,
 
 static grub_err_t
 grub_usbms_write (struct grub_scsi *scsi, grub_size_t cmdsize, char *cmd,
-		  grub_size_t size, char *buf)
+		  grub_size_t size, const char *buf)
 {
-  return grub_usbms_transfer (scsi, cmdsize, cmd, size, buf, 1);
+  return grub_usbms_transfer (scsi, cmdsize, cmd, size, (char *) buf, 1);
 }
 
 static grub_err_t
diff --git a/include/grub/scsi.h b/include/grub/scsi.h
index dfee69c62..e10f5e452 100644
--- a/include/grub/scsi.h
+++ b/include/grub/scsi.h
@@ -69,7 +69,7 @@ struct grub_scsi_dev
   /* Write SIZE  bytes from BUF to  the device SCSI  after sending the
      command CMD of size CMDSIZE.  */
   grub_err_t (*write) (struct grub_scsi *scsi, grub_size_t cmdsize, char *cmd,
-		       grub_size_t size, char *buf);
+		       grub_size_t size, const char *buf);
 
   /* The next scsi device.  */
   struct grub_scsi_dev *next;