x86: apic: Do not use stacked physid_mask_t

We should not use physid_mask_t as a stack based
variable in apic code. This type depends on MAX_APICS
parameter which may be huge enough.

Especially it became a problem with apic NOOP driver which
is portable between 32 bit and 64 bit environment
(where we have really huge MAX_APICS).

So apic driver should operate with pointers and a caller
in turn should aware of allocation physid_mask_t variable.

As a side (but positive) effect -- we may use already
implemented physid_set_mask_of_physid function eliminating
default_apicid_to_cpu_present completely.

Note that physids_coerce and physids_promote turned into static
inline from macro (since macro hides the fact that parameter is
being interpreted as unsigned long, make it explicit).

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <20091109220659.GA5568@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 16 insertions, 19 deletions

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 08a5f420e07b..b4ac2cdcb64f 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -297,20 +297,20 @@ struct apic {
 	int disable_esr;
 
 	int dest_logical;
-	unsigned long (*check_apicid_used)(physid_mask_t bitmap, int apicid);
+	unsigned long (*check_apicid_used)(physid_mask_t *map, int apicid);
 	unsigned long (*check_apicid_present)(int apicid);
 
 	void (*vector_allocation_domain)(int cpu, struct cpumask *retmask);
 	void (*init_apic_ldr)(void);
 
-	physid_mask_t (*ioapic_phys_id_map)(physid_mask_t map);
+	void (*ioapic_phys_id_map)(physid_mask_t *phys_map, physid_mask_t *retmap);
 
 	void (*setup_apic_routing)(void);
 	int (*multi_timer_check)(int apic, int irq);
 	int (*apicid_to_node)(int logical_apicid);
 	int (*cpu_to_logical_apicid)(int cpu);
 	int (*cpu_present_to_apicid)(int mps_cpu);
-	physid_mask_t (*apicid_to_cpu_present)(int phys_apicid);
+	void (*apicid_to_cpu_present)(int phys_apicid, physid_mask_t *retmap);
 	void (*setup_portio_remap)(void);
 	int (*check_phys_apicid_present)(int phys_apicid);
 	void (*enable_apic_mode)(void);
@@ -534,9 +534,9 @@ default_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
 	return (unsigned int)(mask1 & mask2 & mask3);
 }
 
-static inline unsigned long default_check_apicid_used(physid_mask_t bitmap, int apicid)
+static inline unsigned long default_check_apicid_used(physid_mask_t *map, int apicid)
 {
-	return physid_isset(apicid, bitmap);
+	return physid_isset(apicid, *map);
 }
 
 static inline unsigned long default_check_apicid_present(int bit)
@@ -544,9 +544,9 @@ static inline unsigned long default_check_apicid_present(int bit)
 	return physid_isset(bit, phys_cpu_present_map);
 }
 
-static inline physid_mask_t default_ioapic_phys_id_map(physid_mask_t phys_map)
+static inline void default_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap)
 {
-	return phys_map;
+	*retmap = *phys_map;
 }
 
 /* Mapping from cpu number to logical apicid */
@@ -585,11 +585,6 @@ extern int default_cpu_present_to_apicid(int mps_cpu);
 extern int default_check_phys_apicid_present(int phys_apicid);
 #endif
 
-static inline physid_mask_t default_apicid_to_cpu_present(int phys_apicid)
-{
-	return physid_mask_of_physid(phys_apicid);
-}
-
 #endif /* CONFIG_X86_LOCAL_APIC */
 
 #ifdef CONFIG_X86_32
diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h
index 79c94500c0bb..61d90b1331c3 100644
--- a/arch/x86/include/asm/mpspec.h
+++ b/arch/x86/include/asm/mpspec.h
@@ -163,14 +163,16 @@ typedef struct physid_mask physid_mask_t;
 #define physids_shift_left(d, s, n)				\
 	bitmap_shift_left((d).mask, (s).mask, n, MAX_APICS)
 
-#define physids_coerce(map)			((map).mask[0])
+static inline unsigned long physids_coerce(physid_mask_t *map)
+{
+	return map->mask[0];
+}
 
-#define physids_promote(physids)					\
-	({								\
-		physid_mask_t __physid_mask = PHYSID_MASK_NONE;		\
-		__physid_mask.mask[0] = physids;			\
-		__physid_mask;						\
-	})
+static inline void physids_promote(unsigned long physids, physid_mask_t *map)
+{
+	physids_clear(*map);
+	map->mask[0] = physids;
+}
 
 /* Note: will create very large stack frames if physid_mask_t is big */
 #define physid_mask_of_physid(physid)					\