The kernel''s ISA DMA API is just not fitting virtualization
requirements.
While I didn''t get a response on a query regarding the change to
pnpacpi,
I am going to submit both this and the floppy.c change to mainline Linux.
This was tested on 2.6.22.1, and only made apply to 2.6.18 without
further testing.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Index: head-2007-08-07/arch/i386/kernel/setup-xen.c
==================================================================---
head-2007-08-07.orig/arch/i386/kernel/setup-xen.c 2007-08-08 08:33:24.000000000
+0200
+++ head-2007-08-07/arch/i386/kernel/setup-xen.c 2007-08-07 10:40:43.000000000
+0200
@@ -1826,6 +1826,11 @@ void __init setup_arch(char **cmdline_p)
virt_to_mfn(pfn_to_mfn_frame_list_list);
}
+ /* Mark all ISA DMA channels in-use - using them wouldn''t work. */
+ for (i = 0; i < MAX_DMA_CHANNELS; ++i)
+ if (i != 4 && request_dma(i, "xen") != 0)
+ BUG();
+
/*
* NOTE: at this point the bootmem allocator is fully available.
*/
Index: head-2007-08-07/arch/x86_64/kernel/setup-xen.c
==================================================================---
head-2007-08-07.orig/arch/x86_64/kernel/setup-xen.c 2007-08-08
08:33:24.000000000 +0200
+++ head-2007-08-07/arch/x86_64/kernel/setup-xen.c 2007-08-07 10:40:43.000000000
+0200
@@ -863,6 +863,10 @@ void __init setup_arch(char **cmdline_p)
virt_to_mfn(pfn_to_mfn_frame_list_list);
}
+ /* Mark all ISA DMA channels in-use - using them wouldn''t work. */
+ for (i = 0; i < MAX_DMA_CHANNELS; ++i)
+ if (i != 4 && request_dma(i, "xen") != 0)
+ BUG();
}
if (!is_initial_xendomain()) {
Index: head-2007-08-07/drivers/block/floppy.c
==================================================================---
head-2007-08-07.orig/drivers/block/floppy.c 2007-07-09 01:32:17.000000000 +0200
+++ head-2007-08-07/drivers/block/floppy.c 2007-08-07 10:40:43.000000000 +0200
@@ -4397,11 +4397,15 @@ static int floppy_grab_irq_and_dma(void)
if (fd_request_dma()) {
DPRINT("Unable to grab DMA%d for the floppy driver\n",
FLOPPY_DMA);
- fd_free_irq();
- spin_lock_irqsave(&floppy_usage_lock, flags);
- usage_count--;
- spin_unlock_irqrestore(&floppy_usage_lock, flags);
- return -1;
+ if (can_use_virtual_dma & 2)
+ use_virtual_dma = can_use_virtual_dma = 1;
+ if (!(can_use_virtual_dma & 1)) {
+ fd_free_irq();
+ spin_lock_irqsave(&floppy_usage_lock, flags);
+ usage_count--;
+ spin_unlock_irqrestore(&floppy_usage_lock, flags);
+ return -1;
+ }
}
for (fdc = 0; fdc < N_FDC; fdc++) {
Index: head-2007-08-07/drivers/pnp/manager.c
==================================================================---
head-2007-08-07.orig/drivers/pnp/manager.c 2007-04-26 05:08:32.000000000 +0200
+++ head-2007-08-07/drivers/pnp/manager.c 2007-08-07 10:40:43.000000000 +0200
@@ -168,7 +168,7 @@ static int pnp_assign_irq(struct pnp_dev
return 0;
}
-static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
+static void pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
{
resource_size_t *start, *end;
unsigned long *flags;
@@ -179,18 +179,14 @@ static int pnp_assign_dma(struct pnp_dev
1, 3, 5, 6, 7, 0, 2, 4
};
- if (!dev || !rule)
- return -EINVAL;
-
if (idx >= PNP_MAX_DMA) {
pnp_err("More than 2 dmas is incompatible with pnp
specifications.");
- /* pretend we were successful so at least the manager won''t try
again */
- return 1;
+ return;
}
/* check if this resource has been manually set, if so skip */
if (!(dev->res.dma_resource[idx].flags & IORESOURCE_AUTO))
- return 1;
+ return;
start = &dev->res.dma_resource[idx].start;
end = &dev->res.dma_resource[idx].end;
@@ -200,19 +196,17 @@ static int pnp_assign_dma(struct pnp_dev
*flags |= rule->flags | IORESOURCE_DMA;
*flags &= ~IORESOURCE_UNSET;
- if (!rule->map) {
- *flags |= IORESOURCE_DISABLED;
- return 1; /* skip disabled resource requests */
- }
-
for (i = 0; i < 8; i++) {
if(rule->map & (1<<xtab[i])) {
*start = *end = xtab[i];
if(pnp_check_dma(dev, idx))
- return 1;
+ return;
}
}
- return 0;
+#ifdef MAX_DMA_CHANNELS
+ *start = *end = MAX_DMA_CHANNELS;
+#endif
+ *flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
}
/**
@@ -331,8 +325,7 @@ static int pnp_assign_resources(struct p
irq = irq->next;
}
while (dma) {
- if (!pnp_assign_dma(dev, dma, ndma))
- goto fail;
+ pnp_assign_dma(dev, dma, ndma);
ndma++;
dma = dma->next;
}
@@ -367,8 +360,7 @@ static int pnp_assign_resources(struct p
irq = irq->next;
}
while (dma) {
- if (!pnp_assign_dma(dev, dma, ndma))
- goto fail;
+ pnp_assign_dma(dev, dma, ndma);
ndma++;
dma = dma->next;
}
Index: head-2007-08-07/include/asm-i386/mach-xen/asm/floppy.h
==================================================================---
head-2007-08-07.orig/include/asm-i386/mach-xen/asm/floppy.h 2007-08-08
08:33:24.000000000 +0200
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,147 +0,0 @@
-/*
- * Architecture specific parts of the Floppy driver
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this
archive
- * for more details.
- *
- * Copyright (C) 1995
- *
- * Modifications for Xen are Copyright (c) 2004, Keir Fraser.
- */
-#ifndef __ASM_XEN_I386_FLOPPY_H
-#define __ASM_XEN_I386_FLOPPY_H
-
-#include <linux/vmalloc.h>
-
-/* XEN: Hit DMA paths on the head. This trick from asm-m68k/floppy.h. */
-#include <asm/dma.h>
-#undef MAX_DMA_ADDRESS
-#define MAX_DMA_ADDRESS 0
-#define CROSS_64KB(a,s) (0)
-
-#define fd_inb(port) inb_p(port)
-#define fd_outb(value,port) outb_p(value,port)
-
-#define fd_request_dma() (0)
-#define fd_free_dma() ((void)0)
-#define fd_enable_irq() enable_irq(FLOPPY_IRQ)
-#define fd_disable_irq() disable_irq(FLOPPY_IRQ)
-#define fd_free_irq() free_irq(FLOPPY_IRQ, NULL)
-#define fd_get_dma_residue() (virtual_dma_count + virtual_dma_residue)
-#define fd_dma_setup(addr, size, mode, io) vdma_dma_setup(addr, size, mode, io)
-/*
- * Do not use vmalloc/vfree: floppy_release_irq_and_dma() gets called from
- * softirq context via motor_off_callback. A generic bug we happen to trigger.
- */
-#define fd_dma_mem_alloc(size) __get_free_pages(GFP_KERNEL, get_order(size))
-#define fd_dma_mem_free(addr, size) free_pages(addr, get_order(size))
-
-static int virtual_dma_count;
-static int virtual_dma_residue;
-static char *virtual_dma_addr;
-static int virtual_dma_mode;
-static int doing_pdma;
-
-static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
-{
- register unsigned char st;
- register int lcount;
- register char *lptr;
-
- if (!doing_pdma)
- return floppy_interrupt(irq, dev_id, regs);
-
- st = 1;
- for(lcount=virtual_dma_count, lptr=virtual_dma_addr;
- lcount; lcount--, lptr++) {
- st=inb(virtual_dma_port+4) & 0xa0 ;
- if(st != 0xa0)
- break;
- if(virtual_dma_mode)
- outb_p(*lptr, virtual_dma_port+5);
- else
- *lptr = inb_p(virtual_dma_port+5);
- }
- virtual_dma_count = lcount;
- virtual_dma_addr = lptr;
- st = inb(virtual_dma_port+4);
-
- if(st == 0x20)
- return IRQ_HANDLED;
- if(!(st & 0x20)) {
- virtual_dma_residue += virtual_dma_count;
- virtual_dma_count=0;
- doing_pdma = 0;
- floppy_interrupt(irq, dev_id, regs);
- return IRQ_HANDLED;
- }
- return IRQ_HANDLED;
-}
-
-static void fd_disable_dma(void)
-{
- doing_pdma = 0;
- virtual_dma_residue += virtual_dma_count;
- virtual_dma_count=0;
-}
-
-static int fd_request_irq(void)
-{
- return request_irq(FLOPPY_IRQ, floppy_hardint,
- IRQF_DISABLED, "floppy", NULL);
-}
-
-static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
-{
- doing_pdma = 1;
- virtual_dma_port = io;
- virtual_dma_mode = (mode == DMA_MODE_WRITE);
- virtual_dma_addr = addr;
- virtual_dma_count = size;
- virtual_dma_residue = 0;
- return 0;
-}
-
-/* XEN: This trick to force ''virtual DMA'' is from
include/asm-m68k/floppy.h. */
-#define FDC1 xen_floppy_init()
-static int FDC2 = -1;
-
-static int xen_floppy_init(void)
-{
- use_virtual_dma = 1;
- can_use_virtual_dma = 1;
- return 0x3f0;
-}
-
-/*
- * Floppy types are stored in the rtc''s CMOS RAM and so rtc_lock
- * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
- * coincides with another rtc CMOS user. Paul G.
- */
-#define FLOPPY0_TYPE ({ \
- unsigned long flags; \
- unsigned char val; \
- spin_lock_irqsave(&rtc_lock, flags); \
- val = (CMOS_READ(0x10) >> 4) & 15; \
- spin_unlock_irqrestore(&rtc_lock, flags); \
- val; \
-})
-
-#define FLOPPY1_TYPE ({ \
- unsigned long flags; \
- unsigned char val; \
- spin_lock_irqsave(&rtc_lock, flags); \
- val = CMOS_READ(0x10) & 15; \
- spin_unlock_irqrestore(&rtc_lock, flags); \
- val; \
-})
-
-#define N_FDC 2
-#define N_DRIVE 8
-
-#define FLOPPY_MOTOR_MASK 0xf0
-
-#define EXTRA_FLOPPY_PARAMS
-
-#endif /* __ASM_XEN_I386_FLOPPY_H */
Index: head-2007-08-07/include/asm-i386/mach-xen/asm/io.h
==================================================================---
head-2007-08-07.orig/include/asm-i386/mach-xen/asm/io.h 2007-08-08
08:33:56.000000000 +0200
+++ head-2007-08-07/include/asm-i386/mach-xen/asm/io.h 2007-08-08
08:34:11.000000000 +0200
@@ -152,7 +152,7 @@ extern void bt_iounmap(void *addr, unsig
/*
* ISA I/O bus memory addresses are 1:1 with the physical address.
*/
-#define isa_virt_to_bus(_x) isa_virt_to_bus_is_UNSUPPORTED->x
+#define isa_virt_to_bus(_x) ({ BUG(); virt_to_bus(_x); })
#define isa_page_to_bus(_x) isa_page_to_bus_is_UNSUPPORTED->x
#define isa_bus_to_virt(_x) (void *)(__fix_to_virt(FIX_ISAMAP_BEGIN) + (_x))
Index: head-2007-08-07/include/asm-x86_64/mach-xen/asm/floppy.h
==================================================================---
head-2007-08-07.orig/include/asm-x86_64/mach-xen/asm/floppy.h 2007-08-08
08:33:24.000000000 +0200
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,206 +0,0 @@
-/*
- * Architecture specific parts of the Floppy driver
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this
archive
- * for more details.
- *
- * Copyright (C) 1995
- *
- * Modifications for Xen are Copyright (c) 2004, Keir Fraser.
- */
-#ifndef __ASM_XEN_X86_64_FLOPPY_H
-#define __ASM_XEN_X86_64_FLOPPY_H
-
-#include <linux/vmalloc.h>
-
-/*
- * The DMA channel used by the floppy controller cannot access data at
- * addresses >= 16MB
- *
- * Went back to the 1MB limit, as some people had problems with the floppy
- * driver otherwise. It doesn''t matter much for performance anyway, as
most
- * floppy accesses go through the track buffer.
- */
-#define _CROSS_64KB(a,s,vdma) \
-(!(vdma) && ((unsigned long)(a)/K_64 != ((unsigned long)(a) + (s) - 1)
/ K_64))
-
-/* XEN: Hit DMA paths on the head. This trick from asm-m68k/floppy.h. */
-#include <asm/dma.h>
-#undef MAX_DMA_ADDRESS
-#define MAX_DMA_ADDRESS 0
-#define CROSS_64KB(a,s) (0)
-
-#define fd_inb(port) inb_p(port)
-#define fd_outb(value,port) outb_p(value,port)
-
-#define fd_request_dma() (0)
-#define fd_free_dma() ((void)0)
-#define fd_enable_irq() enable_irq(FLOPPY_IRQ)
-#define fd_disable_irq() disable_irq(FLOPPY_IRQ)
-#define fd_free_irq() free_irq(FLOPPY_IRQ, NULL)
-#define fd_get_dma_residue() vdma_get_dma_residue(FLOPPY_DMA)
-/*
- * Do not use vmalloc/vfree: floppy_release_irq_and_dma() gets called from
- * softirq context via motor_off_callback. A generic bug we happen to trigger.
- */
-#define fd_dma_mem_alloc(size) __get_free_pages(GFP_KERNEL|__GFP_NORETRY,
get_order(size))
-#define fd_dma_mem_free(addr, size) free_pages(addr, get_order(size))
-#define fd_dma_setup(addr, size, mode, io) vdma_dma_setup(addr, size, mode, io)
-
-static int virtual_dma_count;
-static int virtual_dma_residue;
-static char *virtual_dma_addr;
-static int virtual_dma_mode;
-static int doing_pdma;
-
-static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
-{
- register unsigned char st;
-
-#undef TRACE_FLPY_INT
-
-#ifdef TRACE_FLPY_INT
- static int calls=0;
- static int bytes=0;
- static int dma_wait=0;
-#endif
- if (!doing_pdma)
- return floppy_interrupt(irq, dev_id, regs);
-
-#ifdef TRACE_FLPY_INT
- if(!calls)
- bytes = virtual_dma_count;
-#endif
-
- {
- register int lcount;
- register char *lptr;
-
- st = 1;
- for(lcount=virtual_dma_count, lptr=virtual_dma_addr;
- lcount; lcount--, lptr++) {
- st=inb(virtual_dma_port+4) & 0xa0 ;
- if(st != 0xa0)
- break;
- if(virtual_dma_mode)
- outb_p(*lptr, virtual_dma_port+5);
- else
- *lptr = inb_p(virtual_dma_port+5);
- }
- virtual_dma_count = lcount;
- virtual_dma_addr = lptr;
- st = inb(virtual_dma_port+4);
- }
-
-#ifdef TRACE_FLPY_INT
- calls++;
-#endif
- if(st == 0x20)
- return IRQ_HANDLED;
- if(!(st & 0x20)) {
- virtual_dma_residue += virtual_dma_count;
- virtual_dma_count=0;
-#ifdef TRACE_FLPY_INT
- printk("count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n",
- virtual_dma_count, virtual_dma_residue, calls, bytes,
- dma_wait);
- calls = 0;
- dma_wait=0;
-#endif
- doing_pdma = 0;
- floppy_interrupt(irq, dev_id, regs);
- return IRQ_HANDLED;
- }
-#ifdef TRACE_FLPY_INT
- if(!virtual_dma_count)
- dma_wait++;
-#endif
- return IRQ_HANDLED;
-}
-
-static void fd_disable_dma(void)
-{
- doing_pdma = 0;
- virtual_dma_residue += virtual_dma_count;
- virtual_dma_count=0;
-}
-
-static int vdma_get_dma_residue(unsigned int dummy)
-{
- return virtual_dma_count + virtual_dma_residue;
-}
-
-
-static int fd_request_irq(void)
-{
- return request_irq(FLOPPY_IRQ, floppy_hardint,
- IRQF_DISABLED, "floppy", NULL);
-}
-
-#if 0
-static unsigned long vdma_mem_alloc(unsigned long size)
-{
- return (unsigned long) vmalloc(size);
-
-}
-
-static void vdma_mem_free(unsigned long addr, unsigned long size)
-{
- vfree((void *)addr);
-}
-#endif
-
-static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
-{
- doing_pdma = 1;
- virtual_dma_port = io;
- virtual_dma_mode = (mode == DMA_MODE_WRITE);
- virtual_dma_addr = addr;
- virtual_dma_count = size;
- virtual_dma_residue = 0;
- return 0;
-}
-
-/* XEN: This trick to force ''virtual DMA'' is from
include/asm-m68k/floppy.h. */
-#define FDC1 xen_floppy_init()
-static int FDC2 = -1;
-
-static int xen_floppy_init(void)
-{
- use_virtual_dma = 1;
- can_use_virtual_dma = 1;
- return 0x3f0;
-}
-
-/*
- * Floppy types are stored in the rtc''s CMOS RAM and so rtc_lock
- * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
- * coincides with another rtc CMOS user. Paul G.
- */
-#define FLOPPY0_TYPE ({ \
- unsigned long flags; \
- unsigned char val; \
- spin_lock_irqsave(&rtc_lock, flags); \
- val = (CMOS_READ(0x10) >> 4) & 15; \
- spin_unlock_irqrestore(&rtc_lock, flags); \
- val; \
-})
-
-#define FLOPPY1_TYPE ({ \
- unsigned long flags; \
- unsigned char val; \
- spin_lock_irqsave(&rtc_lock, flags); \
- val = CMOS_READ(0x10) & 15; \
- spin_unlock_irqrestore(&rtc_lock, flags); \
- val; \
-})
-
-#define N_FDC 2
-#define N_DRIVE 8
-
-#define FLOPPY_MOTOR_MASK 0xf0
-
-#define EXTRA_FLOPPY_PARAMS
-
-#endif /* __ASM_XEN_X86_64_FLOPPY_H */
Index: head-2007-08-07/include/asm-x86_64/mach-xen/asm/io.h
==================================================================---
head-2007-08-07.orig/include/asm-x86_64/mach-xen/asm/io.h 2007-08-07
10:20:55.000000000 +0200
+++ head-2007-08-07/include/asm-x86_64/mach-xen/asm/io.h 2007-08-07
10:40:43.000000000 +0200
@@ -164,7 +164,7 @@ extern void iounmap(volatile void __iome
* ISA I/O bus memory addresses are 1:1 with the physical address.
*/
-#define isa_virt_to_bus(_x) isa_virt_to_bus_is_UNSUPPORTED->x
+#define isa_virt_to_bus(_x) ({ BUG(); virt_to_bus(_x); })
#define isa_page_to_bus(_x) isa_page_to_bus_is_UNSUPPORTED->x
#define isa_bus_to_virt(_x) (void *)(__fix_to_virt(FIX_ISAMAP_BEGIN) + (_x))
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel