* [Patch V3 1/4] iommu/vt-d: replace *hdr with drhd[0] in struct dmar_drhd_unit
2016-03-23 14:15 [Patch V3 0/4] Code refine for Intel IOMMU Wei Yang
@ 2016-03-23 14:15 ` Wei Yang
2016-03-23 14:15 ` [Patch V3 2/4] iommu/vt-d: use zero-sized array in DMAR related ACPI structures Wei Yang
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Wei Yang @ 2016-03-23 14:15 UTC (permalink / raw)
To: joro, jiang.liu, tglx; +Cc: iommu, linux-kernel, Wei Yang
Before commit <6b1972493a84> ("iommu/vt-d: Implement DMAR unit hotplug
framework"),dmaru->hdr just points to the memory region of DMA remapping
hardware definition. In this case, it would have no difference to where we
put hdr.
After this commit, DMA remapping hardware definition is copied and
attach to the end of dmaru structure. By replacing a pointer with a
zero-sized array, that would save some space for this structure.
This patch replace *hdr with drhd[0] in struct dmar_drhd_unit and change
the type from acpi_dmar_header to acpi_dmar_hardware_unit. By doing so, it
reflects the real data type contained in dmar_drhd_unit and avoid some type
cast between them.
Besides this, this patch includes another change:
* remove redundant type cast to the same type in dmar_table_detect()
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
drivers/iommu/dmar.c | 17 +++++------------
drivers/iommu/intel_irq_remapping.c | 10 ++++------
include/linux/dmar.h | 3 ++-
3 files changed, 11 insertions(+), 19 deletions(-)
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 80e3c17..80199b3 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -292,8 +292,7 @@ static int dmar_pci_bus_add_dev(struct dmar_pci_notify_info *info)
if (dmaru->include_all)
continue;
- drhd = container_of(dmaru->hdr,
- struct acpi_dmar_hardware_unit, header);
+ drhd = dmaru->drhd;
ret = dmar_insert_dev_scope(info, (void *)(drhd + 1),
((void *)drhd) + drhd->header.length,
dmaru->segment,
@@ -390,8 +389,7 @@ static int dmar_parse_one_drhd(struct acpi_dmar_header *header, void *arg)
* If header is allocated from slab by ACPI _DSM method, we need to
* copy the content because the memory buffer will be freed on return.
*/
- dmaru->hdr = (void *)(dmaru + 1);
- memcpy(dmaru->hdr, header, header->length);
+ memcpy(dmaru->drhd, drhd, drhd->header.length);
dmaru->reg_base_addr = drhd->address;
dmaru->segment = drhd->segment;
dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
@@ -529,8 +527,7 @@ static int __init dmar_table_detect(void)
/* if we could find DMAR table, then there are DMAR devices */
status = acpi_get_table_with_size(ACPI_SIG_DMAR, 0,
- (struct acpi_table_header **)&dmar_tbl,
- &dmar_tbl_size);
+ &dmar_tbl, &dmar_tbl_size);
if (ACPI_SUCCESS(status) && !dmar_tbl) {
pr_warn("Unable to map DMAR\n");
@@ -663,9 +660,7 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev)
rcu_read_lock();
for_each_drhd_unit(dmaru) {
- drhd = container_of(dmaru->hdr,
- struct acpi_dmar_hardware_unit,
- header);
+ drhd = dmaru->drhd;
if (dmaru->include_all &&
drhd->segment == pci_domain_nr(dev->bus))
@@ -693,9 +688,7 @@ static void __init dmar_acpi_insert_dev_scope(u8 device_number,
struct acpi_dmar_pci_path *path;
for_each_drhd_unit(dmaru) {
- drhd = container_of(dmaru->hdr,
- struct acpi_dmar_hardware_unit,
- header);
+ drhd = dmaru->drhd;
for (scope = (void *)(drhd + 1);
(unsigned long)scope < ((unsigned long)drhd) + drhd->header.length;
diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 1fae188..e35062e 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -886,17 +886,15 @@ static int ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
return 0;
}
-static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_header *header,
+static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_hardware_unit *drhd,
struct intel_iommu *iommu)
{
int ret = 0;
- struct acpi_dmar_hardware_unit *drhd;
struct acpi_dmar_device_scope *scope;
void *start, *end;
- drhd = (struct acpi_dmar_hardware_unit *)header;
start = (void *)(drhd + 1);
- end = ((void *)drhd) + header->length;
+ end = ((void *)drhd) + drhd->header.length;
while (start < end && ret == 0) {
scope = start;
@@ -940,7 +938,7 @@ static int __init parse_ioapics_under_ir(void)
if (!ecap_ir_support(iommu->ecap))
continue;
- ret = ir_parse_ioapic_hpet_scope(drhd->hdr, iommu);
+ ret = ir_parse_ioapic_hpet_scope(drhd->drhd, iommu);
if (ret)
return ret;
@@ -1420,7 +1418,7 @@ static int dmar_ir_add(struct dmar_drhd_unit *dmaru, struct intel_iommu *iommu)
return -ENODEV;
}
- if (ir_parse_ioapic_hpet_scope(dmaru->hdr, iommu)) {
+ if (ir_parse_ioapic_hpet_scope(dmaru->drhd, iommu)) {
pr_warn("DRHD %Lx: failed to parse managed IOAPIC/HPET\n",
iommu->reg_phys);
return -ENODEV;
diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index e9bc929..70ef3cf 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -52,7 +52,6 @@ struct dmar_dev_scope {
extern struct acpi_table_header *dmar_tbl;
struct dmar_drhd_unit {
struct list_head list; /* list of drhd units */
- struct acpi_dmar_header *hdr; /* ACPI header */
u64 reg_base_addr; /* register base address*/
struct dmar_dev_scope *devices;/* target device array */
int devices_cnt; /* target device count */
@@ -60,6 +59,8 @@ struct dmar_drhd_unit {
u8 ignored:1; /* ignore drhd */
u8 include_all:1;
struct intel_iommu *iommu;
+ struct acpi_dmar_hardware_unit drhd[0];
+ /* ACPI Hardware Unit Definition */
};
struct dmar_pci_path {
--
1.7.9.5
^ permalink raw reply [flat|nested] 5+ messages in thread* [Patch V3 2/4] iommu/vt-d: use zero-sized array in DMAR related ACPI structures
2016-03-23 14:15 [Patch V3 0/4] Code refine for Intel IOMMU Wei Yang
2016-03-23 14:15 ` [Patch V3 1/4] iommu/vt-d: replace *hdr with drhd[0] in struct dmar_drhd_unit Wei Yang
@ 2016-03-23 14:15 ` Wei Yang
2016-03-23 14:15 ` [Patch V3 3/4] iommu/vt-d: check Register Base Address at the beginning of dmar_parse_one_drhd() Wei Yang
2016-03-23 14:15 ` [Patch V3 4/4] iommu/vt-d: refine dmar_acpi_dev_scope_init() with dmar_walk_dmar_table() Wei Yang
3 siblings, 0 replies; 5+ messages in thread
From: Wei Yang @ 2016-03-23 14:15 UTC (permalink / raw)
To: joro, jiang.liu, tglx; +Cc: iommu, linux-kernel, Wei Yang
1. DMAR table has variable number of remapping entries
2. DMAR hardware unit has variable number of device scope
3. DMAR device scope has variable number of pci path
In current implementation, we use (head + 1) to access these variable
number elements, which may not be obvious for audience. Zero-sized array is
usually used for this purpose.
This patch adds zero-sized array for variable elements in DMAR ACPI
structures, which tries to make the code more audience friendly.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
drivers/iommu/dmar.c | 22 ++++++++++------------
include/acpi/actbl2.h | 31 +++++++++++++++++--------------
2 files changed, 27 insertions(+), 26 deletions(-)
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 80199b3..6bff602 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -225,7 +225,6 @@ int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
int i, level;
struct device *tmp, *dev = &info->dev->dev;
struct acpi_dmar_device_scope *scope;
- struct acpi_dmar_pci_path *path;
if (segment != info->seg)
return 0;
@@ -236,9 +235,8 @@ int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
scope->entry_type != ACPI_DMAR_SCOPE_TYPE_BRIDGE)
continue;
- path = (struct acpi_dmar_pci_path *)(scope + 1);
- level = (scope->length - sizeof(*scope)) / sizeof(*path);
- if (!dmar_match_pci_path(info, scope->bus, path, level))
+ level = (scope->length - sizeof(*scope)) / sizeof(*scope->path);
+ if (!dmar_match_pci_path(info, scope->bus, scope->path, level))
continue;
if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT) ^
@@ -393,7 +391,7 @@ static int dmar_parse_one_drhd(struct acpi_dmar_header *header, void *arg)
dmaru->reg_base_addr = drhd->address;
dmaru->segment = drhd->segment;
dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
- dmaru->devices = dmar_alloc_dev_scope((void *)(drhd + 1),
+ dmaru->devices = dmar_alloc_dev_scope(drhd->dev_scope,
((void *)drhd) + drhd->header.length,
&dmaru->devices_cnt);
if (dmaru->devices_cnt && dmaru->devices == NULL) {
@@ -579,7 +577,7 @@ static int dmar_walk_remapping_entries(struct acpi_dmar_header *start,
static inline int dmar_walk_dmar_table(struct acpi_table_dmar *dmar,
struct dmar_res_callback *cb)
{
- return dmar_walk_remapping_entries((void *)(dmar + 1),
+ return dmar_walk_remapping_entries(dmar->remapping_entries,
dmar->header.length - sizeof(*dmar), cb);
}
@@ -685,12 +683,11 @@ static void __init dmar_acpi_insert_dev_scope(u8 device_number,
struct acpi_dmar_device_scope *scope;
struct device *tmp;
int i;
- struct acpi_dmar_pci_path *path;
for_each_drhd_unit(dmaru) {
drhd = dmaru->drhd;
- for (scope = (void *)(drhd + 1);
+ for (scope = drhd->dev_scope;
(unsigned long)scope < ((unsigned long)drhd) + drhd->header.length;
scope = ((void *)scope) + scope->length) {
if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_NAMESPACE)
@@ -698,15 +695,16 @@ static void __init dmar_acpi_insert_dev_scope(u8 device_number,
if (scope->enumeration_id != device_number)
continue;
- path = (void *)(scope + 1);
pr_info("ACPI device \"%s\" under DMAR at %llx as %02x:%02x.%d\n",
dev_name(&adev->dev), dmaru->reg_base_addr,
- scope->bus, path->device, path->function);
+ scope->bus, scope->path->device,
+ scope->path->function);
for_each_dev_scope(dmaru->devices, dmaru->devices_cnt, i, tmp)
if (tmp == NULL) {
dmaru->devices[i].bus = scope->bus;
- dmaru->devices[i].devfn = PCI_DEVFN(path->device,
- path->function);
+ dmaru->devices[i].devfn =
+ PCI_DEVFN(scope->path->device,
+ scope->path->function);
rcu_assign_pointer(dmaru->devices[i].dev,
get_device(&adev->dev));
return;
diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
index 6e28f54..fd5c615 100644
--- a/include/acpi/actbl2.h
+++ b/include/acpi/actbl2.h
@@ -403,17 +403,6 @@ struct acpi_table_dbgp {
*
******************************************************************************/
-struct acpi_table_dmar {
- struct acpi_table_header header; /* Common ACPI table header */
- u8 width; /* Host Address Width */
- u8 flags;
- u8 reserved[10];
-};
-
-/* Masks for Flags field above */
-
-#define ACPI_DMAR_INTR_REMAP (1)
-
/* DMAR subtable header */
struct acpi_dmar_header {
@@ -434,12 +423,18 @@ enum acpi_dmar_type {
/* DMAR Device Scope structure */
+struct acpi_dmar_pci_path {
+ u8 device;
+ u8 function;
+};
+
struct acpi_dmar_device_scope {
u8 entry_type;
u8 length;
u16 reserved;
u8 enumeration_id;
u8 bus;
+ struct acpi_dmar_pci_path path[0];
};
/* Values for entry_type in struct acpi_dmar_device_scope - device types */
@@ -454,11 +449,18 @@ enum acpi_dmar_scope_type {
ACPI_DMAR_SCOPE_TYPE_RESERVED = 6 /* 6 and greater are reserved */
};
-struct acpi_dmar_pci_path {
- u8 device;
- u8 function;
+struct acpi_table_dmar {
+ struct acpi_table_header header; /* Common ACPI table header */
+ u8 width; /* Host Address Width */
+ u8 flags;
+ u8 reserved[10];
+ struct acpi_dmar_header remapping_entries[0];
};
+/* Masks for Flags field above */
+
+#define ACPI_DMAR_INTR_REMAP (1)
+
/*
* DMAR Subtables, correspond to Type in struct acpi_dmar_header
*/
@@ -471,6 +473,7 @@ struct acpi_dmar_hardware_unit {
u8 reserved;
u16 segment;
u64 address; /* Register Base Address */
+ struct acpi_dmar_device_scope dev_scope[0];
};
/* Masks for Flags field above */
--
1.7.9.5
^ permalink raw reply [flat|nested] 5+ messages in thread* [Patch V3 3/4] iommu/vt-d: check Register Base Address at the beginning of dmar_parse_one_drhd()
2016-03-23 14:15 [Patch V3 0/4] Code refine for Intel IOMMU Wei Yang
2016-03-23 14:15 ` [Patch V3 1/4] iommu/vt-d: replace *hdr with drhd[0] in struct dmar_drhd_unit Wei Yang
2016-03-23 14:15 ` [Patch V3 2/4] iommu/vt-d: use zero-sized array in DMAR related ACPI structures Wei Yang
@ 2016-03-23 14:15 ` Wei Yang
2016-03-23 14:15 ` [Patch V3 4/4] iommu/vt-d: refine dmar_acpi_dev_scope_init() with dmar_walk_dmar_table() Wei Yang
3 siblings, 0 replies; 5+ messages in thread
From: Wei Yang @ 2016-03-23 14:15 UTC (permalink / raw)
To: joro, jiang.liu, tglx; +Cc: iommu, linux-kernel, Wei Yang
A NULL value of Register Base Address in a Hardware Unit Definition means
it is an invalid dmar. Current implementation checks this value in
alloc_iommu(), by when it has already allocated memory to store itself and
device scope.
This patch moves the check at the beginning of dmar_parse_one_drhd(), so
that it notices this is an invalid dmar and avoids related setup jobs.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
drivers/iommu/dmar.c | 34 +++++++++++++++++-----------------
1 file changed, 17 insertions(+), 17 deletions(-)
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 6bff602..35fc8fb 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -363,6 +363,18 @@ dmar_find_dmaru(struct acpi_dmar_hardware_unit *drhd)
return NULL;
}
+static void warn_invalid_dmar(u64 addr, const char *message)
+{
+ WARN_TAINT_ONCE(
+ 1, TAINT_FIRMWARE_WORKAROUND,
+ "Your BIOS is broken; DMAR reported at address %llx%s!\n"
+ "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+ addr, message,
+ dmi_get_system_info(DMI_BIOS_VENDOR),
+ dmi_get_system_info(DMI_BIOS_VERSION),
+ dmi_get_system_info(DMI_PRODUCT_VERSION));
+}
+
/**
* dmar_parse_one_drhd - parses exactly one DMA remapping hardware definition
* structure which uniquely represent one DMA remapping hardware unit
@@ -379,6 +391,11 @@ static int dmar_parse_one_drhd(struct acpi_dmar_header *header, void *arg)
if (dmaru)
goto out;
+ if (!drhd->address) {
+ warn_invalid_dmar(0, "");
+ return -EINVAL;
+ }
+
dmaru = kzalloc(sizeof(*dmaru) + header->length, GFP_KERNEL);
if (!dmaru)
return -ENOMEM;
@@ -808,18 +825,6 @@ int __init dmar_table_init(void)
return dmar_table_initialized < 0 ? dmar_table_initialized : 0;
}
-static void warn_invalid_dmar(u64 addr, const char *message)
-{
- WARN_TAINT_ONCE(
- 1, TAINT_FIRMWARE_WORKAROUND,
- "Your BIOS is broken; DMAR reported at address %llx%s!\n"
- "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
- addr, message,
- dmi_get_system_info(DMI_BIOS_VENDOR),
- dmi_get_system_info(DMI_BIOS_VERSION),
- dmi_get_system_info(DMI_PRODUCT_VERSION));
-}
-
static int __ref
dmar_validate_one_drhd(struct acpi_dmar_header *entry, void *arg)
{
@@ -995,11 +1000,6 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd)
int msagaw = 0;
int err;
- if (!drhd->reg_base_addr) {
- warn_invalid_dmar(0, "");
- return -EINVAL;
- }
-
iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
if (!iommu)
return -ENOMEM;
--
1.7.9.5
^ permalink raw reply [flat|nested] 5+ messages in thread* [Patch V3 4/4] iommu/vt-d: refine dmar_acpi_dev_scope_init() with dmar_walk_dmar_table()
2016-03-23 14:15 [Patch V3 0/4] Code refine for Intel IOMMU Wei Yang
` (2 preceding siblings ...)
2016-03-23 14:15 ` [Patch V3 3/4] iommu/vt-d: check Register Base Address at the beginning of dmar_parse_one_drhd() Wei Yang
@ 2016-03-23 14:15 ` Wei Yang
3 siblings, 0 replies; 5+ messages in thread
From: Wei Yang @ 2016-03-23 14:15 UTC (permalink / raw)
To: joro, jiang.liu, tglx; +Cc: iommu, linux-kernel, Wei Yang
dmar_acpi_dev_scope_init() iterates on the remapping structure and just do
proper job for ANDD structure. This is the what dmar_walk_dmar_table()
does.
This patch improves the code with dmar_walk_dmar_table().
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
drivers/iommu/dmar.c | 56 ++++++++++++++++++++++++++++----------------------
1 file changed, 32 insertions(+), 24 deletions(-)
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 35fc8fb..6281b45 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -733,36 +733,44 @@ static void __init dmar_acpi_insert_dev_scope(u8 device_number,
device_number, dev_name(&adev->dev));
}
-static int __init dmar_acpi_dev_scope_init(void)
+static int __dmar_acpi_dev_scope_init(struct acpi_dmar_header *header,
+ void *arg)
{
struct acpi_dmar_andd *andd;
+ acpi_handle h;
+ struct acpi_device *adev;
+
+ andd = (struct acpi_dmar_andd *)header;
+ if (!ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT,
+ andd->device_name,
+ &h))) {
+ pr_err("Failed to find handle for ACPI object %s\n",
+ andd->device_name);
+ return 0;
+ }
+ if (acpi_bus_get_device(h, &adev)) {
+ pr_err("Failed to get device for ACPI object %s\n",
+ andd->device_name);
+ return 0;
+ }
+ dmar_acpi_insert_dev_scope(andd->device_number, adev);
+ return 0;
+}
+
+static int __init dmar_acpi_dev_scope_init(void)
+{
+ struct acpi_table_dmar *dmar;
+ struct dmar_res_callback cb = {
+ .print_entry = false,
+ .ignore_unhandled = true,
+ .cb[ACPI_DMAR_TYPE_NAMESPACE] = &__dmar_acpi_dev_scope_init,
+ };
if (dmar_tbl == NULL)
return -ENODEV;
- for (andd = (void *)dmar_tbl + sizeof(struct acpi_table_dmar);
- ((unsigned long)andd) < ((unsigned long)dmar_tbl) + dmar_tbl->length;
- andd = ((void *)andd) + andd->header.length) {
- if (andd->header.type == ACPI_DMAR_TYPE_NAMESPACE) {
- acpi_handle h;
- struct acpi_device *adev;
-
- if (!ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT,
- andd->device_name,
- &h))) {
- pr_err("Failed to find handle for ACPI object %s\n",
- andd->device_name);
- continue;
- }
- if (acpi_bus_get_device(h, &adev)) {
- pr_err("Failed to get device for ACPI object %s\n",
- andd->device_name);
- continue;
- }
- dmar_acpi_insert_dev_scope(andd->device_number, adev);
- }
- }
- return 0;
+ dmar = (struct acpi_table_dmar *)dmar_tbl;
+ return dmar_walk_dmar_table(dmar, &cb);
}
int __init dmar_dev_scope_init(void)
--
1.7.9.5
^ permalink raw reply [flat|nested] 5+ messages in thread