Messages in this thread | | | Subject | Re: [PATCH V7 1/8] ACPI: I/O Remapping Table (IORT) initial support | From | Tomasz Nowicki <> | Date | Wed, 22 Jun 2016 13:06:05 +0200 |
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On 22.06.2016 12:50, Marc Zyngier wrote: > On 21/06/16 08:12, Hanjun Guo wrote: >> Hi Tomasz, >> >> Sorry for jumping out late, just one comment below. >> >> On 2016/6/20 19:02, Tomasz Nowicki wrote: >>> IORT shows representation of IO topology for ARM based systems. >>> It describes how various components are connected together on >>> parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec. >>> >>> Initial support allows to detect IORT table presence and save its >>> root pointer obtained through acpi_get_table(). The pointer validity >>> depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap >>> is not set while using IORT nodes we would dereference unmapped pointers. >>> >>> For the aforementioned reason call iort_table_detect() from acpi_init() >>> which guarantees acpi_gbl_permanent_mmap to be set at that point. >>> >>> Add generic helpers which are helpful for scanning and retrieving >>> information from IORT table content. List of the most important helpers: >>> - iort_find_dev_node() finds IORT node for a given device >>> - iort_node_map_rid() maps device RID and returns IORT node which provides >>> final translation >>> >>> Signed-off-by: Tomasz Nowicki <tn@semihalf.com> >>> --- >>> drivers/acpi/Kconfig | 3 + >>> drivers/acpi/Makefile | 1 + >>> drivers/acpi/bus.c | 2 + >>> drivers/acpi/iort.c | 220 ++++++++++++++++++++++++++++++++++++++++++++++++++ >>> include/linux/iort.h | 30 +++++++ >> >> [...] >> >>> +static acpi_status >>> +iort_match_node_callback(struct acpi_iort_node *node, void *context) >>> +{ >>> + struct device *dev = context; >>> + >>> + switch (node->type) { >>> + case ACPI_IORT_NODE_NAMED_COMPONENT: { >>> + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; >> >> ACPI_ALLOCATE_BUFFER is used here, so ... >> >>> + struct acpi_device *adev = to_acpi_device_node(dev->fwnode); >>> + struct acpi_iort_named_component *ncomp; >>> + >>> + if (!adev) >>> + break; >>> + >>> + ncomp = (struct acpi_iort_named_component *)node->node_data; >>> + >>> + if (ACPI_FAILURE(acpi_get_name(adev->handle, >>> + ACPI_FULL_PATHNAME, &buffer))) { >>> + dev_warn(dev, "Can't get device full path name\n"); >>> + break; >>> + } >>> + >>> + if (!strcmp(ncomp->device_name, (char *)buffer.pointer)) >>> + return AE_OK; >> >> ... we need to kfree(buffer.pointer) before we return or break. > > For the record, I've queued this patch on top: > > diff --git a/drivers/acpi/iort.c b/drivers/acpi/iort.c > index 496dcf6..3b9e55b 100644 > --- a/drivers/acpi/iort.c > +++ b/drivers/acpi/iort.c > @@ -158,11 +158,15 @@ iort_match_node_callback(struct acpi_iort_node *node, void *context) > if (ACPI_FAILURE(acpi_get_name(adev->handle, > ACPI_FULL_PATHNAME, &buffer))) { > dev_warn(dev, "Can't get device full path name\n"); > - break; > - } > + } else { > + int match; > > - if (!strcmp(ncomp->device_name, (char *)buffer.pointer)) > - return AE_OK; > + match = !strcmp(ncomp->device_name, buffer.pointer); > + acpi_os_free(&buffer); > + > + if (match) > + return AE_OK; > + } > > break; > } > > > assuming that Rafael is OK with the general approach, of course. >
Thanks Marc. As Lorenzo pointed out, we need another fix for iort_node_map_rid(). Do you want me to refresh the whole series or this patch only?
Tomasz
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