This patch introduces two new interfaces, pci_mmconfig_insert() and
pci_mmconfig_delete(), to support PCI host bridge hotplug on x86 platforms.
Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx>
---
arch/x86/include/asm/pci_x86.h | 4 +
arch/x86/pci/mmconfig-shared.c | 186 +++++++++++++++++++++++++++++++---------
arch/x86/pci/mmconfig_32.c | 28 ++++++-
arch/x86/pci/mmconfig_64.c | 35 +++++++-
4 files changed, 206 insertions(+), 47 deletions(-)
diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index b3a5317..ba8570c 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -135,6 +135,10 @@ struct pci_mmcfg_region {
extern int __init pci_mmcfg_arch_init(void);
extern void __init pci_mmcfg_arch_free(void);
+extern int __devinit pci_mmcfg_arch_map(struct pci_mmcfg_region *cfg);
+extern void __devinit pci_mmcfg_arch_unmap(struct pci_mmcfg_region *cfg);
+extern int __devinit pci_mmconfig_insert(int seg, int start, int end, u64 addr);
+extern int __devinit pci_mmconfig_delete(int seg, int start, int end, u64 addr);
extern struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus);
extern struct list_head pci_mmcfg_list;
diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 301e325..dda9470 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -17,6 +17,8 @@
#include <linux/bitmap.h>
#include <linux/dmi.h>
#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/rculist.h>
#include <asm/e820.h>
#include <asm/pci_x86.h>
#include <asm/acpi.h>
@@ -45,24 +47,25 @@ static __init void free_all_mmcfg(void)
pci_mmconfig_remove(cfg);
}
-static __init void list_add_sorted(struct pci_mmcfg_region *new)
+static __devinit void list_add_sorted(struct pci_mmcfg_region *new)
{
struct pci_mmcfg_region *cfg;
/* keep list sorted by segment and starting bus number */
- list_for_each_entry(cfg, &pci_mmcfg_list, list) {
+ list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) {
if (cfg->segment > new->segment ||
(cfg->segment == new->segment &&
cfg->start_bus >= new->start_bus)) {
- list_add_tail(&new->list, &cfg->list);
+ list_add_tail_rcu(&new->list, &cfg->list);
return;
}
}
- list_add_tail(&new->list, &pci_mmcfg_list);
+ list_add_tail_rcu(&new->list, &pci_mmcfg_list);
}
-static __init struct pci_mmcfg_region *pci_mmconfig_add(int segment, int start,
- int end, u64 addr)
+static __devinit struct pci_mmcfg_region *pci_mmconfig_alloc(int segment,
+ int start,
+ int end, u64 addr)
{
struct pci_mmcfg_region *new;
struct resource *res;
@@ -79,8 +82,6 @@ static __init struct pci_mmcfg_region *pci_mmconfig_add(int segment, int start,
new->start_bus = start;
new->end_bus = end;
- list_add_sorted(new);
-
res = &new->res;
res->start = addr + PCI_MMCFG_BUS_OFFSET(start);
res->end = addr + PCI_MMCFG_BUS_OFFSET(end + 1) - 1;
@@ -96,11 +97,23 @@ static __init struct pci_mmcfg_region *pci_mmconfig_add(int segment, int start,
return new;
}
+static __init struct pci_mmcfg_region *pci_mmconfig_add(int segment, int start,
+ int end, u64 addr)
+{
+ struct pci_mmcfg_region *new;
+
+ new = pci_mmconfig_alloc(segment, start, end, addr);
+ if (new)
+ list_add_sorted(new);
+
+ return new;
+}
+
struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus)
{
struct pci_mmcfg_region *cfg;
- list_for_each_entry(cfg, &pci_mmcfg_list, list)
+ list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list)
if (cfg->segment == segment &&
cfg->start_bus <= bus && bus <= cfg->end_bus)
return cfg;
@@ -364,8 +377,8 @@ static void __init pci_mmcfg_insert_resources(void)
pci_mmcfg_resources_inserted = 1;
}
-static acpi_status __init check_mcfg_resource(struct acpi_resource *res,
- void *data)
+static acpi_status __devinit check_mcfg_resource(struct acpi_resource *res,
+ void *data)
{
struct resource *mcfg_res = data;
struct acpi_resource_address64 address;
@@ -401,8 +414,8 @@ static acpi_status __init check_mcfg_resource(struct acpi_resource *res,
return AE_OK;
}
-static acpi_status __init find_mboard_resource(acpi_handle handle, u32 lvl,
- void *context, void **rv)
+static acpi_status __devinit find_mboard_resource(acpi_handle handle, u32 lvl,
+ void *context, void **rv)
{
struct resource *mcfg_res = context;
@@ -415,7 +428,7 @@ static acpi_status __init find_mboard_resource(acpi_handle handle, u32 lvl,
return AE_OK;
}
-static int __init is_acpi_reserved(u64 start, u64 end, unsigned not_used)
+static int __devinit is_acpi_reserved(u64 start, u64 end, unsigned not_used)
{
struct resource mcfg_res;
@@ -434,8 +447,9 @@ static int __init is_acpi_reserved(u64 start, u64 end, unsigned not_used)
typedef int (*check_reserved_t)(u64 start, u64 end, unsigned type);
-static int __init is_mmconf_reserved(check_reserved_t is_reserved,
- struct pci_mmcfg_region *cfg, int with_e820)
+static int __devinit is_mmconf_reserved(check_reserved_t is_reserved,
+ struct pci_mmcfg_region *cfg,
+ int with_e820)
{
u64 addr = cfg->res.start;
u64 size = resource_size(&cfg->res);
@@ -474,39 +488,38 @@ static int __init is_mmconf_reserved(check_reserved_t is_reserved,
return valid;
}
+static int __devinit pci_mmcfg_check_reserved(struct pci_mmcfg_region *cfg,
+ int early)
+{
+ if (!early && !acpi_disabled) {
+ if (is_mmconf_reserved(is_acpi_reserved, cfg, 0))
+ return 1;
+ else
+ printk(KERN_ERR FW_BUG PREFIX
+ "MMCONFIG at %pR not reserved in "
+ "ACPI motherboard resources\n",
+ &cfg->res);
+ }
+
+ /* Don't try to do this check unless configuration
+ type 1 is available. how about type 2 ?*/
+ if (raw_pci_ops)
+ return is_mmconf_reserved(e820_all_mapped, cfg, 1);
+
+ return 0;
+}
+
static void __init pci_mmcfg_reject_broken(int early)
{
struct pci_mmcfg_region *cfg;
list_for_each_entry(cfg, &pci_mmcfg_list, list) {
- int valid = 0;
-
- if (!early && !acpi_disabled) {
- valid = is_mmconf_reserved(is_acpi_reserved, cfg, 0);
-
- if (valid)
- continue;
- else
- printk(KERN_ERR FW_BUG PREFIX
- "MMCONFIG at %pR not reserved in "
- "ACPI motherboard resources\n",
- &cfg->res);
+ if (pci_mmcfg_check_reserved(cfg, early) == 0) {
+ printk(KERN_INFO PREFIX "not using MMCONFIG\n");
+ free_all_mmcfg();
+ return;
}
-
- /* Don't try to do this check unless configuration
- type 1 is available. how about type 2 ?*/
- if (raw_pci_ops)
- valid = is_mmconf_reserved(e820_all_mapped, cfg, 1);
-
- if (!valid)
- goto reject;
}
-
- return;
-
-reject:
- printk(KERN_INFO PREFIX "not using MMCONFIG\n");
- free_all_mmcfg();
}
static int __initdata known_bridge;
@@ -665,3 +678,92 @@ static int __init pci_mmcfg_late_insert_resources(void)
* with other system resources.
*/
late_initcall(pci_mmcfg_late_insert_resources);
+
+static DEFINE_MUTEX(pci_mmcfg_lock);
+
+/* Add MMCFG information for hot-added host bridges at runtime */
+int __devinit pci_mmconfig_insert(int segment, int start, int end, u64 addr)
+{
+ int rc;
+ struct pci_mmcfg_region *cfg = NULL;
+
+ if (addr == 0 || segment < 0 || segment > USHRT_MAX ||
+ start < 0 || start > 255 || end < start || end > 255)
+ return -EINVAL;
+
+ mutex_lock(&pci_mmcfg_lock);
+ cfg = pci_mmconfig_lookup(segment, start);
+ if (cfg) {
+ if (cfg->start_bus == start && cfg->end_bus == end &&
+ cfg->address == addr) {
+ rc = -EEXIST;
+ } else {
+ rc = -EINVAL;
+ printk(KERN_WARNING PREFIX
+ "MMCONFIG for domain %04x [bus %02x-%02x] "
+ "conflicts with domain %04x [bus %02x-%02x]\n",
+ segment, start, end,
+ cfg->segment, cfg->start_bus, cfg->end_bus);
+ }
+ goto out;
+ }
+
+ cfg = pci_mmconfig_alloc(segment, start, end, addr);
+ if (cfg == NULL) {
+ rc = -ENOMEM;
+ } else if (!pci_mmcfg_check_reserved(cfg, 0)) {
+ rc = -EINVAL;
+ printk(KERN_WARNING PREFIX
+ "MMCONFIG for domain %04x [bus %02x-%02x] "
+ "isn't reserved\n", segment, start, end);
+ } else if (insert_resource(&iomem_resource, &cfg->res)) {
+ rc = -EBUSY;
+ printk(KERN_WARNING PREFIX
+ "failed to insert resource for domain "
+ "%04x [bus %02x-%02x]\n", segment, start, end);
+ } else if (pci_mmcfg_arch_map(cfg)) {
+ rc = -EBUSY;
+ printk(KERN_WARNING PREFIX
+ "failed to map resource for domain "
+ "%04x [bus %02x-%02x]\n", segment, start, end);
+ } else {
+ list_add_sorted(cfg);
+ cfg = NULL;
+ rc = 0;
+ }
+
+ if (cfg) {
+ if (cfg->res.parent)
+ release_resource(&cfg->res);
+ kfree(cfg);
+ }
+
+out:
+ mutex_unlock(&pci_mmcfg_lock);
+
+ return rc;
+}
+
+/* Delete MMCFG information at runtime */
+int __devinit pci_mmconfig_delete(int segment, int start, int end, u64 addr)
+{
+ struct pci_mmcfg_region *cfg;
+
+ mutex_lock(&pci_mmcfg_lock);
+ list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) {
+ if (cfg->segment == segment && cfg->start_bus == start &&
+ cfg->end_bus == end && cfg->address == addr) {
+ list_del_rcu(&cfg->list);
+ synchronize_rcu();
+ pci_mmcfg_arch_unmap(cfg);
+ if (cfg->res.parent)
+ release_resource(&cfg->res);
+ mutex_unlock(&pci_mmcfg_lock);
+ kfree(cfg);
+ return 0;
+ }
+ }
+ mutex_unlock(&pci_mmcfg_lock);
+
+ return -ENOENT;
+}
diff --git a/arch/x86/pci/mmconfig_32.c b/arch/x86/pci/mmconfig_32.c
index 5372e86..c2756de 100644
--- a/arch/x86/pci/mmconfig_32.c
+++ b/arch/x86/pci/mmconfig_32.c
@@ -11,6 +11,7 @@
#include <linux/pci.h>
#include <linux/init.h>
+#include <linux/rcupdate.h>
#include <asm/e820.h>
#include <asm/pci_x86.h>
#include <acpi/acpi.h>
@@ -60,9 +61,12 @@ err: *value = -1;
return -EINVAL;
}
+ rcu_read_lock();
base = get_base_addr(seg, bus, devfn);
- if (!base)
+ if (!base) {
+ rcu_read_unlock();
goto err;
+ }
raw_spin_lock_irqsave(&pci_config_lock, flags);
@@ -80,6 +84,7 @@ err: *value = -1;
break;
}
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
+ rcu_read_unlock();
return 0;
}
@@ -93,9 +98,12 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
if ((bus > 255) || (devfn > 255) || (reg > 4095))
return -EINVAL;
+ rcu_read_lock();
base = get_base_addr(seg, bus, devfn);
- if (!base)
+ if (!base) {
+ rcu_read_unlock();
return -EINVAL;
+ }
raw_spin_lock_irqsave(&pci_config_lock, flags);
@@ -113,6 +121,7 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
break;
}
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
+ rcu_read_unlock();
return 0;
}
@@ -132,3 +141,18 @@ int __init pci_mmcfg_arch_init(void)
void __init pci_mmcfg_arch_free(void)
{
}
+
+int __devinit pci_mmcfg_arch_map(struct pci_mmcfg_region *cfg)
+{
+ return 0;
+}
+
+void __devinit pci_mmcfg_arch_unmap(struct pci_mmcfg_region *cfg)
+{
+ unsigned long flags;
+
+ /* Invalidate the cached mmcfg map entry. */
+ raw_spin_lock_irqsave(&pci_config_lock, flags);
+ mmcfg_last_accessed_device = 0;
+ raw_spin_unlock_irqrestore(&pci_config_lock, flags);
+}
diff --git a/arch/x86/pci/mmconfig_64.c b/arch/x86/pci/mmconfig_64.c
index 915a493..6822dd6 100644
--- a/arch/x86/pci/mmconfig_64.c
+++ b/arch/x86/pci/mmconfig_64.c
@@ -9,6 +9,7 @@
#include <linux/init.h>
#include <linux/acpi.h>
#include <linux/bitmap.h>
+#include <linux/rcupdate.h>
#include <asm/e820.h>
#include <asm/pci_x86.h>
@@ -34,9 +35,12 @@ err: *value = -1;
return -EINVAL;
}
+ rcu_read_lock();
addr = pci_dev_base(seg, bus, devfn);
- if (!addr)
+ if (!addr) {
+ rcu_read_unlock();
goto err;
+ }
switch (len) {
case 1:
@@ -49,6 +53,7 @@ err: *value = -1;
*value = mmio_config_readl(addr + reg);
break;
}
+ rcu_read_unlock();
return 0;
}
@@ -62,9 +67,12 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
return -EINVAL;
+ rcu_read_lock();
addr = pci_dev_base(seg, bus, devfn);
- if (!addr)
+ if (!addr) {
+ rcu_read_unlock();
return -EINVAL;
+ }
switch (len) {
case 1:
@@ -77,6 +85,7 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
mmio_config_writel(addr + reg, value);
break;
}
+ rcu_read_unlock();
return 0;
}
@@ -86,7 +95,7 @@ static const struct pci_raw_ops pci_mmcfg = {
.write = pci_mmcfg_write,
};
-static void __iomem * __init mcfg_ioremap(struct pci_mmcfg_region *cfg)
+static void __iomem * __devinit mcfg_ioremap(struct pci_mmcfg_region *cfg)
{
void __iomem *addr;
u64 start, size;
@@ -129,3 +138,23 @@ void __init pci_mmcfg_arch_free(void)
}
}
}
+
+int __devinit pci_mmcfg_arch_map(struct pci_mmcfg_region *cfg)
+{
+ cfg->virt = mcfg_ioremap(cfg);
+ if (!cfg->virt) {
+ printk(KERN_ERR PREFIX "can't map MMCONFIG at %pR\n",
+ &cfg->res);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+void __devinit pci_mmcfg_arch_unmap(struct pci_mmcfg_region *cfg)
+{
+ if (cfg && cfg->virt) {
+ iounmap(cfg->virt + PCI_MMCFG_BUS_OFFSET(cfg->start_bus));
+ cfg->virt = NULL;
+ }
+}
--
1.7.5.4
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