Hi, All,
I am very sorry for my miss. Please cancel these two patches. I will send the
new patches.
Best Regards,
Jin Dongming.
(2010/09/02 11:31), Jin Dongming wrote:
> acpi_pre_map() is used for remapping the physical address of I/O, so
> it should be return NULL or remapped virtual address. The problem is
> that when (paddr - pg_off) equals 0, no matter whether I/O remapping is
> successful or not, the function returns NULL.
>
> In acpi_pre_map(), after the physical address is remapped sucessfully,
> it will check whether the physical address has been added into acpi_iomaps
> list again.
> - If the physical address has beed added into acpi_iomaps, the virtual
> address will be saved in vaddr.
> - Otherwise, NULL be saved in vaddr.
>
> So if the physical address is the first time to be remapped, vaddr will be
> NULL always.
>
> In many cases, (paddr - pg_off) may not equal 0. So the function could work
> well. In our machine, (paddr - pg_off) equals 0, so the return value of
> acpi_pre_map() is NULL.
>
> This patch fixed it and I confirmed it on x86_64 next-tree.
>
> Signed-off-by: Jin Dongming <jin.dongming@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/acpi/atomicio.c | 4 ++--
> 1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/acpi/atomicio.c b/drivers/acpi/atomicio.c
> index 8f8bd73..1bc2614 100644
> --- a/drivers/acpi/atomicio.c
> +++ b/drivers/acpi/atomicio.c
> @@ -133,7 +133,7 @@ static void __iomem *acpi_pre_map(phys_addr_t paddr,
>
> spin_lock_irqsave(&acpi_iomaps_lock, flags);
> vaddr = __acpi_try_ioremap(paddr, size);
> - if (vaddr) {
> + if (unlikely(vaddr)) {
> spin_unlock_irqrestore(&acpi_iomaps_lock, flags);
> iounmap(map->vaddr);
> kfree(map);
> @@ -142,7 +142,7 @@ static void __iomem *acpi_pre_map(phys_addr_t paddr,
> list_add_tail_rcu(&map->list, &acpi_iomaps);
> spin_unlock_irqrestore(&acpi_iomaps_lock, flags);
>
> - return vaddr + (paddr - pg_off);
> + return map->vaddr + (paddr - pg_off);
> err_unmap:
> iounmap(vaddr);
> return NULL;
> -- 1.7.1.1
>
> --
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