X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fdevices%2Fdisk.c;fp=src%2Fdevices%2Fdisk.c;h=2bae0577ff044ec07657711cae1d7586338b9c49;hb=00562fc78061b83b6fff5231d5581ad55497265a;hp=0a131740b00711bc94af611330518d9e919b18f5;hpb=b2b72dd2a4460d2e670aad3444270e2aefa5fa85;p=pintos-anon

diff --git a/src/devices/disk.c b/src/devices/disk.c
index 0a13174..2bae057 100644
--- a/src/devices/disk.c
+++ b/src/devices/disk.c
@@ -30,6 +30,7 @@
 
 /* Alternate Status Register bits. */
 #define STA_BSY 0x80            /* Busy. */
+#define STA_DRDY 0x40           /* Device Ready. */
 #define STA_DRQ 0x08            /* Data Request. */
 
 /* Control Register bits. */
@@ -331,15 +332,18 @@ static bool
 check_device_type (struct disk *d) 
 {
   struct channel *c = d->channel;
-  uint8_t error, lbam, lbah;
+  uint8_t error, lbam, lbah, status;
 
   select_device (d);
 
   error = inb (reg_error (c));
   lbam = inb (reg_lbam (c));
   lbah = inb (reg_lbah (c));
+  status = inb (reg_status (c));
 
-  if (error != 1 && (error != 0x81 || d->dev_no == 1)) 
+  if ((error != 1 && (error != 0x81 || d->dev_no == 1))
+      || (status & STA_DRDY) == 0
+      || (status & STA_BSY) != 0)
     {
       d->is_ata = false;
       return error != 0x81;