diff --git a/ide.c b/ide.c index 89c8941627..cfe5728df9 100644 --- a/ide.c +++ b/ide.c @@ -18,14 +18,14 @@ #define IDE_CMD_READ 0x20 #define IDE_CMD_WRITE 0x30 -// ide_queue points to the buf now being read/written to the disk. -// ide_queue->qnext points to the next buf to be processed. -// You must hold ide_lock while manipulating queue. +// idequeue points to the buf now being read/written to the disk. +// idequeue->qnext points to the next buf to be processed. +// You must hold idelock while manipulating queue. -static struct spinlock ide_lock; -static struct buf *ide_queue; +static struct spinlock idelock; +static struct buf *idequeue; -static int disk_1_present; +static int havedisk1; static void idestart(struct buf*); // Wait for IDE disk to become ready. @@ -34,7 +34,7 @@ idewait(int check_error) { int r; - while(((r = inb(0x1f7)) & IDE_BSY) || !(r & IDE_DRDY)) + while(((r = inb(0x1f7)) & (IDE_BSY|IDE_DRDY)) != IDE_DRDY) ; if(check_error && (r & (IDE_DF|IDE_ERR)) != 0) return -1; @@ -46,7 +46,7 @@ ideinit(void) { int i; - initlock(&ide_lock, "ide"); + initlock(&idelock, "ide"); picenable(IRQ_IDE); ioapicenable(IRQ_IDE, ncpu - 1); idewait(0); @@ -55,7 +55,7 @@ ideinit(void) outb(0x1f6, 0xe0 | (1<<4)); for(i=0; i<1000; i++){ if(inb(0x1f7) != 0){ - disk_1_present = 1; + havedisk1 = 1; break; } } @@ -64,7 +64,7 @@ ideinit(void) outb(0x1f6, 0xe0 | (0<<4)); } -// Start the request for b. Caller must hold ide_lock. +// Start the request for b. Caller must hold idelock. static void idestart(struct buf *b) { @@ -92,11 +92,14 @@ ideintr(void) { struct buf *b; - acquire(&ide_lock); - if((b = ide_queue) == 0){ - release(&ide_lock); + // Take first buffer off queue. + acquire(&idelock); + if((b = idequeue) == 0){ + release(&idelock); + cprintf("Spurious IDE interrupt.\n"); return; } + idequeue = b->qnext; // Read data if needed. if(!(b->flags & B_DIRTY) && idewait(1) >= 0) @@ -108,10 +111,10 @@ ideintr(void) wakeup(b); // Start disk on next buf in queue. - if((ide_queue = b->qnext) != 0) - idestart(ide_queue); + if(idequeue != 0) + idestart(idequeue); - release(&ide_lock); + release(&idelock); } //PAGEBREAK! @@ -127,25 +130,25 @@ iderw(struct buf *b) panic("iderw: buf not busy"); if((b->flags & (B_VALID|B_DIRTY)) == B_VALID) panic("iderw: nothing to do"); - if(b->dev != 0 && !disk_1_present) + if(b->dev != 0 && !havedisk1) panic("idrw: ide disk 1 not present"); - acquire(&ide_lock); + acquire(&idelock); - // Append b to ide_queue. + // Append b to idequeue. b->qnext = 0; - for(pp=&ide_queue; *pp; pp=&(*pp)->qnext) + for(pp=&idequeue; *pp; pp=&(*pp)->qnext) ; *pp = b; // Start disk if necessary. - if(ide_queue == b) + if(idequeue == b) idestart(b); // Wait for request to finish. // Assuming will not sleep too long: ignore cp->killed. while((b->flags & (B_VALID|B_DIRTY)) != B_VALID) - sleep(b, &ide_lock); + sleep(b, &idelock); - release(&ide_lock); + release(&idelock); }