READ CAPACITY (16) turns out to be an optional command (even though

READ(16) is mandatory); we must use READ CAPACITY (10) first and then
use READ CAPACITY (16) if the READ CAPACITY (10) returns "out of range".

diff --git a/src/drivers/block/scsi.c b/src/drivers/block/scsi.c
index 1a1d70d..1e906e1 100644 (file)
--- a/src/drivers/block/scsi.c
+++ b/src/drivers/block/scsi.c
@@ -96,12 +96,41 @@ static int scsi_write ( struct block_device *blockdev, uint64_t block,
 }
 
 /**
- * Read capacity of SCSI device
+ * Read capacity of SCSI device via READ CAPACITY (10)
  *
  * @v blockdev         Block device
  * @ret rc             Return status code
  */
-static int scsi_read_capacity ( struct block_device *blockdev ) {
+static int scsi_read_capacity_10 ( struct block_device *blockdev ) {
+       struct scsi_device *scsi = block_to_scsi ( blockdev );
+       struct scsi_command command;
+       struct scsi_cdb_read_capacity_10 *cdb = &command.cdb.readcap10;
+       struct scsi_capacity_10 capacity;
+       int rc;
+
+       /* Issue READ CAPACITY (10) */
+       memset ( &command, 0, sizeof ( command ) );
+       cdb->opcode = SCSI_OPCODE_READ_CAPACITY_10;
+       command.data_in = virt_to_user ( &capacity );
+       command.data_in_len = sizeof ( capacity );
+
+       if ( ( rc = scsi_command ( scsi, &command ) ) != 0 )
+               return rc;
+
+       /* Fill in block device fields */
+       blockdev->blksize = be32_to_cpu ( capacity.blksize );
+       blockdev->blocks = ( be32_to_cpu ( capacity.lba ) + 1 );
+
+       return 0;
+}
+
+/**
+ * Read capacity of SCSI device via READ CAPACITY (16)
+ *
+ * @v blockdev         Block device
+ * @ret rc             Return status code
+ */
+static int scsi_read_capacity_16 ( struct block_device *blockdev ) {
        struct scsi_device *scsi = block_to_scsi ( blockdev );
        struct scsi_command command;
        struct scsi_cdb_read_capacity_16 *cdb = &command.cdb.readcap16;
@@ -125,6 +154,32 @@ static int scsi_read_capacity ( struct block_device *blockdev ) {
        return 0;
 }
 
+/**
+ * Read capacity of SCSI device
+ *
+ * @v blockdev         Block device
+ * @ret rc             Return status code
+ */
+static int scsi_read_capacity ( struct block_device *blockdev ) {
+       int rc;
+
+       /* Try READ CAPACITY (10), which is a mandatory command, first. */
+       if ( ( rc = scsi_read_capacity_10 ( blockdev ) ) != 0 )
+               return rc;
+
+       /* If capacity range was exceeded (i.e. capacity.lba was
+        * 0xffffffff, meaning that blockdev->blocks is now zero), use
+        * READ CAPACITY (16) instead.  READ CAPACITY (16) is not
+        * mandatory, so we can't just use it straight off.
+        */
+       if ( blockdev->blocks == 0 ) {
+               if ( ( rc = scsi_read_capacity_16 ( blockdev ) ) != 0 )
+                       return rc;
+       }
+
+       return 0;
+}
+
 /**
  * Initialise SCSI device
  *

diff --git a/src/include/gpxe/scsi.h b/src/include/gpxe/scsi.h
index d7da125..d5620ef 100644 (file)
--- a/src/include/gpxe/scsi.h
+++ b/src/include/gpxe/scsi.h
@@ -12,6 +12,7 @@
 
 #define SCSI_OPCODE_READ_16            0x88    /**< READ (16) */
 #define SCSI_OPCODE_WRITE_16           0x8a    /**< WRITE (16) */
+#define SCSI_OPCODE_READ_CAPACITY_10   0x25    /**< READ CAPACITY (10) */
 #define SCSI_OPCODE_SERVICE_ACTION_IN  0x9e    /**< SERVICE ACTION IN */
 #define SCSI_SERVICE_ACTION_READ_CAPACITY_16 0x10 /**< READ CAPACITY (16) */
 
@@ -77,6 +78,31 @@ struct scsi_cdb_write_16 {
        uint8_t control;
 } __attribute__ (( packed ));
 
+/** A SCSI "READ CAPACITY (10)" CDB */
+struct scsi_cdb_read_capacity_10 {
+       /** Opcode (0x25) */
+       uint8_t opcode;
+       /** Reserved */
+       uint8_t reserved_a;
+       /** Logical block address
+        *
+        * Applicable only if the PMI bit is set.
+        */
+       uint32_t lba;
+       /** Reserved */
+       uint8_t reserved_b[3];
+       /** Control byte */
+       uint8_t control;        
+} __attribute__ (( packed ));
+
+/** SCSI "READ CAPACITY (10)" parameter data */
+struct scsi_capacity_10 {
+       /** Maximum logical block number */
+       uint32_t lba;
+       /** Block length in bytes */
+       uint32_t blksize;
+} __attribute__ (( packed ));
+
 /** A SCSI "READ CAPACITY (16)" CDB */
 struct scsi_cdb_read_capacity_16 {
        /** Opcode (0x9e) */
@@ -113,6 +139,7 @@ struct scsi_capacity_16 {
 union scsi_cdb {
        struct scsi_cdb_read_16 read16;
        struct scsi_cdb_write_16 write16;
+       struct scsi_cdb_read_capacity_10 readcap10;
        struct scsi_cdb_read_capacity_16 readcap16;
        char bytes[16];
 };