Revision fea6d607e154cf96ab22254ccb48addfd43d4cb5 authored by Alan Stern on 17 February 2012, 21:25:08 UTC, committed by James Bottomley on 18 February 2012, 14:54:19 UTC
This patch (as1520) fixes a bug in the SCSI layer's power management implementation. LUN scanning can be carried out asynchronously in do_scan_async(), and sd uses an asynchronous thread for the time-consuming parts of disk probing in sd_probe_async(). Currently nothing coordinates these async threads with system sleep transitions; they can and do attempt to continue scanning/probing SCSI devices even after the host adapter has been suspended. As one might expect, the outcome is not ideal. This is what the "prepare" stage of system suspend was created for. After the prepare callback has been called for a host, target, or device, drivers are not allowed to register any children underneath them. Currently the SCSI prepare callback is not implemented; this patch rectifies that omission. For SCSI hosts, the prepare routine calls scsi_complete_async_scans() to wait until async scanning is finished. It might be slightly more efficient to wait only until the host in question has been scanned, but there's currently no way to do that. Besides, during a sleep transition we will ultimately have to wait until all the host scanning has finished anyway. For SCSI devices, the prepare routine calls async_synchronize_full() to wait until sd probing is finished. The routine does nothing for SCSI targets, because asynchronous target scanning is done only as part of host scanning. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: <stable@kernel.org> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
1 parent 267a6ad
iomap.c
/*
* Implement the default iomap interfaces
*
* (C) Copyright 2004 Linus Torvalds
*/
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/module.h>
/*
* Read/write from/to an (offsettable) iomem cookie. It might be a PIO
* access or a MMIO access, these functions don't care. The info is
* encoded in the hardware mapping set up by the mapping functions
* (or the cookie itself, depending on implementation and hw).
*
* The generic routines don't assume any hardware mappings, and just
* encode the PIO/MMIO as part of the cookie. They coldly assume that
* the MMIO IO mappings are not in the low address range.
*
* Architectures for which this is not true can't use this generic
* implementation and should do their own copy.
*/
#ifndef HAVE_ARCH_PIO_SIZE
/*
* We encode the physical PIO addresses (0-0xffff) into the
* pointer by offsetting them with a constant (0x10000) and
* assuming that all the low addresses are always PIO. That means
* we can do some sanity checks on the low bits, and don't
* need to just take things for granted.
*/
#define PIO_OFFSET 0x10000UL
#define PIO_MASK 0x0ffffUL
#define PIO_RESERVED 0x40000UL
#endif
static void bad_io_access(unsigned long port, const char *access)
{
static int count = 10;
if (count) {
count--;
WARN(1, KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);
}
}
/*
* Ugly macros are a way of life.
*/
#define IO_COND(addr, is_pio, is_mmio) do { \
unsigned long port = (unsigned long __force)addr; \
if (port >= PIO_RESERVED) { \
is_mmio; \
} else if (port > PIO_OFFSET) { \
port &= PIO_MASK; \
is_pio; \
} else \
bad_io_access(port, #is_pio ); \
} while (0)
#ifndef pio_read16be
#define pio_read16be(port) swab16(inw(port))
#define pio_read32be(port) swab32(inl(port))
#endif
#ifndef mmio_read16be
#define mmio_read16be(addr) be16_to_cpu(__raw_readw(addr))
#define mmio_read32be(addr) be32_to_cpu(__raw_readl(addr))
#endif
unsigned int ioread8(void __iomem *addr)
{
IO_COND(addr, return inb(port), return readb(addr));
return 0xff;
}
unsigned int ioread16(void __iomem *addr)
{
IO_COND(addr, return inw(port), return readw(addr));
return 0xffff;
}
unsigned int ioread16be(void __iomem *addr)
{
IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
return 0xffff;
}
unsigned int ioread32(void __iomem *addr)
{
IO_COND(addr, return inl(port), return readl(addr));
return 0xffffffff;
}
unsigned int ioread32be(void __iomem *addr)
{
IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
return 0xffffffff;
}
EXPORT_SYMBOL(ioread8);
EXPORT_SYMBOL(ioread16);
EXPORT_SYMBOL(ioread16be);
EXPORT_SYMBOL(ioread32);
EXPORT_SYMBOL(ioread32be);
#ifndef pio_write16be
#define pio_write16be(val,port) outw(swab16(val),port)
#define pio_write32be(val,port) outl(swab32(val),port)
#endif
#ifndef mmio_write16be
#define mmio_write16be(val,port) __raw_writew(be16_to_cpu(val),port)
#define mmio_write32be(val,port) __raw_writel(be32_to_cpu(val),port)
#endif
void iowrite8(u8 val, void __iomem *addr)
{
IO_COND(addr, outb(val,port), writeb(val, addr));
}
void iowrite16(u16 val, void __iomem *addr)
{
IO_COND(addr, outw(val,port), writew(val, addr));
}
void iowrite16be(u16 val, void __iomem *addr)
{
IO_COND(addr, pio_write16be(val,port), mmio_write16be(val, addr));
}
void iowrite32(u32 val, void __iomem *addr)
{
IO_COND(addr, outl(val,port), writel(val, addr));
}
void iowrite32be(u32 val, void __iomem *addr)
{
IO_COND(addr, pio_write32be(val,port), mmio_write32be(val, addr));
}
EXPORT_SYMBOL(iowrite8);
EXPORT_SYMBOL(iowrite16);
EXPORT_SYMBOL(iowrite16be);
EXPORT_SYMBOL(iowrite32);
EXPORT_SYMBOL(iowrite32be);
/*
* These are the "repeat MMIO read/write" functions.
* Note the "__raw" accesses, since we don't want to
* convert to CPU byte order. We write in "IO byte
* order" (we also don't have IO barriers).
*/
#ifndef mmio_insb
static inline void mmio_insb(void __iomem *addr, u8 *dst, int count)
{
while (--count >= 0) {
u8 data = __raw_readb(addr);
*dst = data;
dst++;
}
}
static inline void mmio_insw(void __iomem *addr, u16 *dst, int count)
{
while (--count >= 0) {
u16 data = __raw_readw(addr);
*dst = data;
dst++;
}
}
static inline void mmio_insl(void __iomem *addr, u32 *dst, int count)
{
while (--count >= 0) {
u32 data = __raw_readl(addr);
*dst = data;
dst++;
}
}
#endif
#ifndef mmio_outsb
static inline void mmio_outsb(void __iomem *addr, const u8 *src, int count)
{
while (--count >= 0) {
__raw_writeb(*src, addr);
src++;
}
}
static inline void mmio_outsw(void __iomem *addr, const u16 *src, int count)
{
while (--count >= 0) {
__raw_writew(*src, addr);
src++;
}
}
static inline void mmio_outsl(void __iomem *addr, const u32 *src, int count)
{
while (--count >= 0) {
__raw_writel(*src, addr);
src++;
}
}
#endif
void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
}
void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
}
void ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
}
EXPORT_SYMBOL(ioread8_rep);
EXPORT_SYMBOL(ioread16_rep);
EXPORT_SYMBOL(ioread32_rep);
void iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
{
IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
}
void iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
{
IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
}
void iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
{
IO_COND(addr, outsl(port, src,count), mmio_outsl(addr, src, count));
}
EXPORT_SYMBOL(iowrite8_rep);
EXPORT_SYMBOL(iowrite16_rep);
EXPORT_SYMBOL(iowrite32_rep);
#ifdef CONFIG_HAS_IOPORT
/* Create a virtual mapping cookie for an IO port range */
void __iomem *ioport_map(unsigned long port, unsigned int nr)
{
if (port > PIO_MASK)
return NULL;
return (void __iomem *) (unsigned long) (port + PIO_OFFSET);
}
void ioport_unmap(void __iomem *addr)
{
/* Nothing to do */
}
EXPORT_SYMBOL(ioport_map);
EXPORT_SYMBOL(ioport_unmap);
#endif /* CONFIG_HAS_IOPORT */
#ifdef CONFIG_PCI
/* Hide the details if this is a MMIO or PIO address space and just do what
* you expect in the correct way. */
void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
{
IO_COND(addr, /* nothing */, iounmap(addr));
}
EXPORT_SYMBOL(pci_iounmap);
#endif /* CONFIG_PCI */
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...