[PATCH 1/2] powerpc: Add spinlock to request_phb_iospace()

From: Benjamin Herrenschmidt
Date: Tue May 15 2007 - 00:04:32 EST


request_phb_iospace() can be called from different CPUs at init
time (at least with my next patch) and thus needs a spinlock. As
for the next patch, this is a temporary workaround for 2.6.22
issues until my rewrite of IO mappings is ready (for 2.6.23)

Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>

arch/powerpc/mm/pgtable_64.c | 4 ++++
1 file changed, 4 insertions(+)

Index: linux-cell/arch/powerpc/mm/pgtable_64.c
===================================================================
--- linux-cell.orig/arch/powerpc/mm/pgtable_64.c 2007-05-15 13:17:59.000000000 +1000
+++ linux-cell/arch/powerpc/mm/pgtable_64.c 2007-05-15 13:18:32.000000000 +1000
@@ -322,6 +322,8 @@ EXPORT_SYMBOL(__ioremap);
EXPORT_SYMBOL(iounmap);
EXPORT_SYMBOL(__iounmap);

+static DEFINE_SPINLOCK(phb_io_lock);
+
void __iomem * reserve_phb_iospace(unsigned long size)
{
void __iomem *virt_addr;
@@ -329,8 +331,10 @@ void __iomem * reserve_phb_iospace(unsig
if (phbs_io_bot >= IMALLOC_BASE)
panic("reserve_phb_iospace(): phb io space overflow\n");

+ spin_lock(&phb_io_lock);
virt_addr = (void __iomem *) phbs_io_bot;
phbs_io_bot += size;
+ spin_unlock(&phb_io_lock);

return virt_addr;
}
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/