[PATCH v5 1/4] resource: Move reparent_resources() to kernel/resource.c and make it public

Baoquan He
2018-06-12T03:29:27Z

reparent_resources() is duplicated in arch/microblaze/pci/pci-common.c
and arch/powerpc/kernel/pci-common.c, so move it to kernel/resource.c
so that it's shared. Later its code also need be updated using list_head
to replace singly linked list.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
---
v4->v5:
Fix several code bugs reported by test robot on ARCH powerpc and
microblaze.

v3->v4:
Fix several bugs test robot reported. And change patch log.

v2->v3:
Rename resource functions first_child() and sibling() to
resource_first_chils() and resource_sibling(). Dan suggested this.

Move resource_first_chils() and resource_sibling() to linux/ioport.h
and make them as inline function. Rob suggested this. Accordingly add
linux/list.h including in linux/ioport.h, please help review if this
bring efficiency degradation or code redundancy.

The change on struct resource {} bring two pointers of size increase,
mention this in git log to make it more specifically, Rob suggested
this.

arch/microblaze/pci/pci-common.c | 37 -------------------------------------
arch/powerpc/kernel/pci-common.c | 35 -----------------------------------
include/linux/ioport.h | 1 +
kernel/resource.c | 36 ++++++++++++++++++++++++++++++++++++
4 files changed, 37 insertions(+), 72 deletions(-)

diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index f34346d56095..7899bafab064 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -619,43 +619,6 @@ int pcibios_add_device(struct pci_dev *dev)
EXPORT_SYMBOL(pcibios_add_device);

/*
- * Reparent resource children of pr that conflict with res
- * under res, and make res replace those children.
- */
-static int __init reparent_resources(struct resource *parent,
- struct resource *res)
-{
- struct resource *p, **pp;
- struct resource **firstpp = NULL;
-
- for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
- if (p->end < res->start)
- continue;
- if (res->end < p->start)
- break;
- if (p->start < res->start || p->end > res->end)
- return -1; /* not completely contained */
- if (firstpp == NULL)
- firstpp = pp;
- }
- if (firstpp == NULL)
- return -1; /* didn't find any conflicting entries? */
- res->parent = parent;
- res->child = *firstpp;
- res->sibling = *pp;
- *firstpp = res;
- *pp = NULL;
- for (p = res->child; p != NULL; p = p->sibling) {
- p->parent = res;
- pr_debug("PCI: Reparented %s [%llx..%llx] under %s\n",
- p->name,
- (unsigned long long)p->start,
- (unsigned long long)p->end, res->name);
- }
- return 0;
-}
-
-/*
* Handle resources of PCI devices. If the world were perfect, we could
* just allocate all the resource regions and do nothing more. It isn't.
* On the other hand, we cannot just re-allocate all devices, as it would
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index fe9733ffffaa..926035bb378d 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -1088,41 +1088,6 @@ resource_size_t pcibios_align_resource(void *data, const struct resource *res,
EXPORT_SYMBOL(pcibios_align_resource);

/*
- * Reparent resource children of pr that conflict with res
- * under res, and make res replace those children.
- */
-static int reparent_resources(struct resource *parent,
- struct resource *res)
-{
- struct resource *p, **pp;
- struct resource **firstpp = NULL;
-
- for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
- if (p->end < res->start)
- continue;
- if (res->end < p->start)
- break;
- if (p->start < res->start || p->end > res->end)
- return -1; /* not completely contained */
- if (firstpp == NULL)
- firstpp = pp;
- }
- if (firstpp == NULL)
- return -1; /* didn't find any conflicting entries? */
- res->parent = parent;
- res->child = *firstpp;
- res->sibling = *pp;
- *firstpp = res;
- *pp = NULL;
- for (p = res->child; p != NULL; p = p->sibling) {
- p->parent = res;
- pr_debug("PCI: Reparented %s %pR under %s\n",
- p->name, p, res->name);
- }
- return 0;
-}
-
-/*
* Handle resources of PCI devices. If the world were perfect, we could
* just allocate all the resource regions and do nothing more. It isn't.
* On the other hand, we cannot just re-allocate all devices, as it would
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index da0ebaec25f0..dfdcd0bfe54e 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -192,6 +192,7 @@ extern int allocate_resource(struct resource *root, struct resource *new,
struct resource *lookup_resource(struct resource *root, resource_size_t start);
int adjust_resource(struct resource *res, resource_size_t start,
resource_size_t size);
+int reparent_resources(struct resource *parent, struct resource *res);
resource_size_t resource_alignment(struct resource *res);
static inline resource_size_t resource_size(const struct resource *res)
{
diff --git a/kernel/resource.c b/kernel/resource.c
index 30e1bc68503b..5e7c56d5d838 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -983,6 +983,42 @@ int adjust_resource(struct resource *res, resource_size_t start,
}
EXPORT_SYMBOL(adjust_resource);

+/*
+ * Reparent resource children of pr that conflict with res
+ * under res, and make res replace those children.
+ */
+static int reparent_resources(struct resource *parent,
+ struct resource *res)
+{
+ struct resource *p, **pp;
+ struct resource **firstpp = NULL;
+
+ for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
+ if (p->end < res->start)
+ continue;
+ if (res->end < p->start)
+ break;
+ if (p->start < res->start || p->end > res->end)
+ return -1; /* not completely contained */
+ if (firstpp == NULL)
+ firstpp = pp;
+ }
+ if (firstpp == NULL)
+ return -1; /* didn't find any conflicting entries? */
+ res->parent = parent;
+ res->child = *firstpp;
+ res->sibling = *pp;
+ *firstpp = res;
+ *pp = NULL;
+ for (p = res->child; p != NULL; p = p->sibling) {
+ p->parent = res;
+ pr_debug("PCI: Reparented %s %pR under %s\n",
+ p->name, p, res->name);
+ }
+ return 0;
+}
+EXPORT_SYMBOL(reparent_resources);
+
static void __init __reserve_region_with_split(struct resource *root,
resource_size_t start, resource_size_t end,
const char *name)
--
2.13.6