Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  x86: avoid high BIOS area when allocating address space
  x86: avoid E820 regions when allocating address space
  x86: avoid low BIOS area when allocating address space
  resources: add arch hook for preventing allocation in reserved areas
  Revert "resources: support allocating space within a region from the top down"
  Revert "PCI: allocate bus resources from the top down"
  Revert "x86/PCI: allocate space from the end of a region, not the beginning"
  Revert "x86: allocate space within a region top-down"
  Revert "PCI: fix pci_bus_alloc_resource() hang, prefer positive decode"
  PCI: Update MCP55 quirk to not affect non HyperTransport variants

Documentation/kernel-parameters.txt

@@ -2175,11 +2175,6 @@ and is between 256 and 4096 characters. It is defined in the file
 	reset_devices	[KNL] Force drivers to reset the underlying device
 			during initialization.
 
-	resource_alloc_from_bottom
-			Allocate new resources from the beginning of available
-			space, not the end.  If you need to use this, please
-			report a bug.
-
 	resume=		[SWSUSP]
 			Specify the partition device for software suspend
 

arch/x86/include/asm/e820.h

@@ -72,6 +72,9 @@ struct e820map {
 #define BIOS_BEGIN		0x000a0000
 #define BIOS_END		0x00100000
 
+#define BIOS_ROM_BASE		0xffe00000
+#define BIOS_ROM_END		0xffffffff
+
 #ifdef __KERNEL__
 /* see comment in arch/x86/kernel/e820.c */
 extern struct e820map e820;

arch/x86/kernel/Makefile

@@ -45,6 +45,7 @@ obj-y			+= pci-dma.o quirks.o i8237.o topology.o kdebugfs.o
 obj-y			+= alternative.o i8253.o pci-nommu.o hw_breakpoint.o
 obj-y			+= tsc.o io_delay.o rtc.o
 obj-y			+= pci-iommu_table.o
+obj-y			+= resource.o
 
 obj-$(CONFIG_X86_TRAMPOLINE)	+= trampoline.o
 obj-y				+= process.o

arch/x86/kernel/resource.c

+#include <linux/ioport.h>
+#include <asm/e820.h>
+
+static void resource_clip(struct resource *res, resource_size_t start,
+			  resource_size_t end)
+{
+	resource_size_t low = 0, high = 0;
+
+	if (res->end < start || res->start > end)
+		return;		/* no conflict */
+
+	if (res->start < start)
+		low = start - res->start;
+
+	if (res->end > end)
+		high = res->end - end;
+
+	/* Keep the area above or below the conflict, whichever is larger */
+	if (low > high)
+		res->end = start - 1;
+	else
+		res->start = end + 1;
+}
+
+static void remove_e820_regions(struct resource *avail)
+{
+	int i;
+	struct e820entry *entry;
+
+	for (i = 0; i < e820.nr_map; i++) {
+		entry = &e820.map[i];
+
+		resource_clip(avail, entry->addr,
+			      entry->addr + entry->size - 1);
+	}
+}
+
+void arch_remove_reservations(struct resource *avail)
+{
+	/* Trim out BIOS areas (low 1MB and high 2MB) and E820 regions */
+	if (avail->flags & IORESOURCE_MEM) {
+		if (avail->start < BIOS_END)
+			avail->start = BIOS_END;
+		resource_clip(avail, BIOS_ROM_BASE, BIOS_ROM_END);
+
+		remove_e820_regions(avail);
+	}
+}

arch/x86/kernel/setup.c

@@ -769,7 +769,6 @@ void __init setup_arch(char **cmdline_p)
 
 	x86_init.oem.arch_setup();
 
-	resource_alloc_from_bottom = 0;
 	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
 	setup_memory_map();
 	parse_setup_data();

arch/x86/pci/i386.c

@@ -65,21 +65,13 @@ pcibios_align_resource(void *data, const struct resource *res,
 			resource_size_t size, resource_size_t align)
 {
 	struct pci_dev *dev = data;
-	resource_size_t start = round_down(res->end - size + 1, align);
+	resource_size_t start = res->start;
 
 	if (res->flags & IORESOURCE_IO) {
-
-		/*
-		 * If we're avoiding ISA aliases, the largest contiguous I/O
-		 * port space is 256 bytes.  Clearing bits 9 and 10 preserves
-		 * all 256-byte and smaller alignments, so the result will
-		 * still be correctly aligned.
-		 */
-		if (!skip_isa_ioresource_align(dev))
-			start &= ~0x300;
-	} else if (res->flags & IORESOURCE_MEM) {
-		if (start < BIOS_END)
-			start = res->end;	/* fail; no space */
+		if (skip_isa_ioresource_align(dev))
+			return start;
+		if (start & 0x300)
+			start = (start + 0x3ff) & ~0x3ff;
 	}
 	return start;
 }

drivers/pci/bus.c

@@ -64,77 +64,6 @@ void pci_bus_remove_resources(struct pci_bus *bus)
 	}
 }
 
-static bool pci_bus_resource_better(struct resource *res1, bool pos1,
-				    struct resource *res2, bool pos2)
-{
-	/* If exactly one is positive decode, always prefer that one */
-	if (pos1 != pos2)
-		return pos1 ? true : false;
-
-	/* Prefer the one that contains the highest address */
-	if (res1->end != res2->end)
-		return (res1->end > res2->end) ? true : false;
-
-	/* Otherwise, prefer the one with highest "center of gravity" */
-	if (res1->start != res2->start)
-		return (res1->start > res2->start) ? true : false;
-
-	/* Otherwise, choose one arbitrarily (but consistently) */
-	return (res1 > res2) ? true : false;
-}
-
-static bool pci_bus_resource_positive(struct pci_bus *bus, struct resource *res)
-{
-	struct pci_bus_resource *bus_res;
-
-	/*
-	 * This relies on the fact that pci_bus.resource[] refers to P2P or
-	 * CardBus bridge base/limit registers, which are always positively
-	 * decoded.  The pci_bus.resources list contains host bridge or
-	 * subtractively decoded resources.
-	 */
-	list_for_each_entry(bus_res, &bus->resources, list) {
-		if (bus_res->res == res)
-			return (bus_res->flags & PCI_SUBTRACTIVE_DECODE) ?
-				false : true;
-	}
-	return true;
-}
-
-/*
- * Find the next-best bus resource after the cursor "res".  If the cursor is
- * NULL, return the best resource.  "Best" means that we prefer positive
- * decode regions over subtractive decode, then those at higher addresses.
- */
-static struct resource *pci_bus_find_resource_prev(struct pci_bus *bus,
-						   unsigned int type,
-						   struct resource *res)
-{
-	bool res_pos, r_pos, prev_pos = false;
-	struct resource *r, *prev = NULL;
-	int i;
-
-	res_pos = pci_bus_resource_positive(bus, res);
-	pci_bus_for_each_resource(bus, r, i) {
-		if (!r)
-			continue;
-
-		if ((r->flags & IORESOURCE_TYPE_BITS) != type)
-			continue;
-
-		r_pos = pci_bus_resource_positive(bus, r);
-		if (!res || pci_bus_resource_better(res, res_pos, r, r_pos)) {
-			if (!prev || pci_bus_resource_better(r, r_pos,
-							     prev, prev_pos)) {
-				prev = r;
-				prev_pos = r_pos;
-			}
-		}
-	}
-
-	return prev;
-}
-
 /**
  * pci_bus_alloc_resource - allocate a resource from a parent bus
  * @bus: PCI bus
@@ -160,10 +89,9 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
 					  resource_size_t),
 		void *alignf_data)
 {
-	int ret = -ENOMEM;
+	int i, ret = -ENOMEM;
 	struct resource *r;
 	resource_size_t max = -1;
-	unsigned int type = res->flags & IORESOURCE_TYPE_BITS;
 
 	type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
 
@@ -171,9 +99,10 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
 	if (!(res->flags & IORESOURCE_MEM_64))
 		max = PCIBIOS_MAX_MEM_32;
 
-	/* Look for space at highest addresses first */
-	r = pci_bus_find_resource_prev(bus, type, NULL);
-	for ( ; r; r = pci_bus_find_resource_prev(bus, type, r)) {
+	pci_bus_for_each_resource(bus, r, i) {
+		if (!r)
+			continue;
+
 		/* type_mask must match */
 		if ((res->flags ^ r->flags) & type_mask)
 			continue;

drivers/pci/quirks.c

@@ -2329,6 +2329,9 @@ static void __devinit nvbridge_check_legacy_irq_routing(struct pci_dev *dev)
 {
 	u32 cfg;
 
+	if (!pci_find_capability(dev, PCI_CAP_ID_HT))
+		return;
+
 	pci_read_config_dword(dev, 0x74, &cfg);
 
 	if (cfg & ((1 << 2) | (1 << 15))) {

include/linux/ioport.h

@@ -112,7 +112,6 @@ struct resource_list {
 /* PC/ISA/whatever - the normal PC address spaces: IO and memory */
 extern struct resource ioport_resource;
 extern struct resource iomem_resource;
-extern int resource_alloc_from_bottom;
 
 extern struct resource *request_resource_conflict(struct resource *root, struct resource *new);
 extern int request_resource(struct resource *root, struct resource *new);
@@ -124,6 +123,7 @@ extern void reserve_region_with_split(struct resource *root,
 extern struct resource *insert_resource_conflict(struct resource *parent, struct resource *new);
 extern int insert_resource(struct resource *parent, struct resource *new);
 extern void insert_resource_expand_to_fit(struct resource *root, struct resource *new);
+extern void arch_remove_reservations(struct resource *avail);
 extern int allocate_resource(struct resource *root, struct resource *new,
 			     resource_size_t size, resource_size_t min,
 			     resource_size_t max, resource_size_t align,

kernel/resource.c

@@ -40,23 +40,6 @@ EXPORT_SYMBOL(iomem_resource);
 
 static DEFINE_RWLOCK(resource_lock);
 
-/*
- * By default, we allocate free space bottom-up.  The architecture can request
- * top-down by clearing this flag.  The user can override the architecture's
- * choice with the "resource_alloc_from_bottom" kernel boot option, but that
- * should only be a debugging tool.
- */
-int resource_alloc_from_bottom = 1;
-
-static __init int setup_alloc_from_bottom(char *s)
-{
-	printk(KERN_INFO
-	       "resource: allocating from bottom-up; please report a bug\n");
-	resource_alloc_from_bottom = 1;
-	return 0;
-}
-early_param("resource_alloc_from_bottom", setup_alloc_from_bottom);
-
 static void *r_next(struct seq_file *m, void *v, loff_t *pos)
 {
 	struct resource *p = v;
@@ -374,6 +357,10 @@ int __weak page_is_ram(unsigned long pfn)
 	return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
 }
 
+void __weak arch_remove_reservations(struct resource *avail)
+{
+}
+
 static resource_size_t simple_align_resource(void *data,
 					     const struct resource *avail,
 					     resource_size_t size,
@@ -396,75 +383,8 @@ static bool resource_contains(struct resource *res1, struct resource *res2)
 	return res1->start <= res2->start && res1->end >= res2->end;
 }
 
-/*
- * Find the resource before "child" in the sibling list of "root" children.
- */
-static struct resource *find_sibling_prev(struct resource *root, struct resource *child)
-{
-	struct resource *this;
-
-	for (this = root->child; this; this = this->sibling)
-		if (this->sibling == child)
-			return this;
-
-	return NULL;
-}
-
 /*
  * Find empty slot in the resource tree given range and alignment.
- * This version allocates from the end of the root resource first.
- */
-static int find_resource_from_top(struct resource *root, struct resource *new,
-				  resource_size_t size, resource_size_t min,
-				  resource_size_t max, resource_size_t align,
-				  resource_size_t (*alignf)(void *,
-						   const struct resource *,
-						   resource_size_t,
-						   resource_size_t),
-				  void *alignf_data)
-{
-	struct resource *this;
-	struct resource tmp, avail, alloc;
-
-	tmp.start = root->end;
-	tmp.end = root->end;
-
-	this = find_sibling_prev(root, NULL);
-	for (;;) {
-		if (this) {
-			if (this->end < root->end)
-				tmp.start = this->end + 1;
-		} else
-			tmp.start = root->start;
-
-		resource_clip(&tmp, min, max);
-
-		/* Check for overflow after ALIGN() */
-		avail = *new;
-		avail.start = ALIGN(tmp.start, align);
-		avail.end = tmp.end;
-		if (avail.start >= tmp.start) {
-			alloc.start = alignf(alignf_data, &avail, size, align);
-			alloc.end = alloc.start + size - 1;
-			if (resource_contains(&avail, &alloc)) {
-				new->start = alloc.start;
-				new->end = alloc.end;
-				return 0;
-			}
-		}
-
-		if (!this || this->start == root->start)
-			break;
-
-		tmp.end = this->start - 1;
-		this = find_sibling_prev(root, this);
-	}
-	return -EBUSY;
-}
-
-/*
- * Find empty slot in the resource tree given range and alignment.
- * This version allocates from the beginning of the root resource first.
  */
 static int find_resource(struct resource *root, struct resource *new,
 			 resource_size_t size, resource_size_t min,
@@ -478,23 +398,24 @@ static int find_resource(struct resource *root, struct resource *new,
 	struct resource *this = root->child;
 	struct resource tmp = *new, avail, alloc;
 
+	tmp.flags = new->flags;
 	tmp.start = root->start;
 	/*
-	 * Skip past an allocated resource that starts at 0, since the
-	 * assignment of this->start - 1 to tmp->end below would cause an
-	 * underflow.
+	 * Skip past an allocated resource that starts at 0, since the assignment
+	 * of this->start - 1 to tmp->end below would cause an underflow.
 	 */
 	if (this && this->start == 0) {
 		tmp.start = this->end + 1;
 		this = this->sibling;
 	}
-	for (;;) {
+	for(;;) {
 		if (this)
 			tmp.end = this->start - 1;
 		else
 			tmp.end = root->end;
 
 		resource_clip(&tmp, min, max);
+		arch_remove_reservations(&tmp);
 
 		/* Check for overflow after ALIGN() */
 		avail = *new;
@@ -509,10 +430,8 @@ static int find_resource(struct resource *root, struct resource *new,
 				return 0;
 			}
 		}
-
 		if (!this)
 			break;
-
 		tmp.start = this->end + 1;
 		this = this->sibling;
 	}
@@ -545,10 +464,7 @@ int allocate_resource(struct resource *root, struct resource *new,
 		alignf = simple_align_resource;
 
 	write_lock(&resource_lock);
-	if (resource_alloc_from_bottom)
 	err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
-	else
-		err = find_resource_from_top(root, new, size, min, max, align, alignf, alignf_data);
 	if (err >= 0 && __request_resource(root, new))
 		err = -EBUSY;
 	write_unlock(&resource_lock);