Use the relatively new scope based of_node_put() cleanup to simplify
function exit handling. Doing so reduces the chances of forgetting an
of_node_put() and simplifies error paths by avoiding the need for goto
statements.
Signed-off-by: Rob Herring <[email protected]>
---
drivers/of/address.c | 60 ++++++++++++++++-----------------------------------
drivers/of/property.c | 22 ++++++-------------
2 files changed, 26 insertions(+), 56 deletions(-)
diff --git a/drivers/of/address.c b/drivers/of/address.c
index ae46a3605904..f7b2d535a6d1 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -491,7 +491,6 @@ static u64 __of_translate_address(struct device_node *dev,
const __be32 *in_addr, const char *rprop,
struct device_node **host)
{
- struct device_node *parent = NULL;
struct of_bus *bus, *pbus;
__be32 addr[OF_MAX_ADDR_CELLS];
int na, ns, pna, pns;
@@ -504,7 +503,7 @@ static u64 __of_translate_address(struct device_node *dev,
*host = NULL;
/* Get parent & match bus type */
- parent = get_parent(dev);
+ struct device_node *parent __free(device_node) = get_parent(dev);
if (parent == NULL)
goto bail;
bus = of_match_bus(parent);
@@ -573,7 +572,6 @@ static u64 __of_translate_address(struct device_node *dev,
of_dump_addr("one level translation:", addr, na);
}
bail:
- of_node_put(parent);
of_node_put(dev);
return result;
@@ -654,19 +652,16 @@ EXPORT_SYMBOL(of_translate_dma_address);
const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop,
phys_addr_t *start, size_t *length)
{
- struct device_node *parent;
+ struct device_node *parent __free(device_node) = __of_get_dma_parent(dev);
u64 address, size;
int na, ns;
- parent = __of_get_dma_parent(dev);
if (!parent)
return NULL;
na = of_bus_n_addr_cells(parent);
ns = of_bus_n_size_cells(parent);
- of_node_put(parent);
-
address = of_translate_dma_address(dev, prop);
if (address == OF_BAD_ADDR)
return NULL;
@@ -688,21 +683,19 @@ const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no,
{
const __be32 *prop;
unsigned int psize;
- struct device_node *parent;
+ struct device_node *parent __free(device_node) = of_get_parent(dev);
struct of_bus *bus;
int onesize, i, na, ns;
- /* Get parent & match bus type */
- parent = of_get_parent(dev);
if (parent == NULL)
return NULL;
+
+ /* match the parent's bus type */
bus = of_match_bus(parent);
- if (strcmp(bus->name, "pci") && (bar_no >= 0)) {
- of_node_put(parent);
+ if (strcmp(bus->name, "pci") && (bar_no >= 0))
return NULL;
- }
+
bus->count_cells(dev, &na, &ns);
- of_node_put(parent);
if (!OF_CHECK_ADDR_COUNT(na))
return NULL;
@@ -888,14 +881,13 @@ static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
*/
int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
{
- struct device_node *node = of_node_get(np);
+ struct device_node *node __free(device_node) = of_node_get(np);
const __be32 *ranges = NULL;
bool found_dma_ranges = false;
struct of_range_parser parser;
struct of_range range;
struct bus_dma_region *r;
int len, num_ranges = 0;
- int ret = 0;
while (node) {
ranges = of_get_property(node, "dma-ranges", &len);
@@ -905,10 +897,9 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
break;
/* Once we find 'dma-ranges', then a missing one is an error */
- if (found_dma_ranges && !ranges) {
- ret = -ENODEV;
- goto out;
- }
+ if (found_dma_ranges && !ranges)
+ return -ENODEV;
+
found_dma_ranges = true;
node = of_get_next_dma_parent(node);
@@ -916,10 +907,8 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
if (!node || !ranges) {
pr_debug("no dma-ranges found for node(%pOF)\n", np);
- ret = -ENODEV;
- goto out;
+ return -ENODEV;
}
-
of_dma_range_parser_init(&parser, node);
for_each_of_range(&parser, &range) {
if (range.cpu_addr == OF_BAD_ADDR) {
@@ -930,16 +919,12 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
num_ranges++;
}
- if (!num_ranges) {
- ret = -EINVAL;
- goto out;
- }
+ if (!num_ranges)
+ return -EINVAL;
r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
- if (!r) {
- ret = -ENOMEM;
- goto out;
- }
+ if (!r)
+ return -ENOMEM;
/*
* Record all info in the generic DMA ranges array for struct device,
@@ -957,9 +942,7 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
r->size = range.size;
r++;
}
-out:
- of_node_put(node);
- return ret;
+ return 0;
}
#endif /* CONFIG_HAS_DMA */
@@ -1016,11 +999,9 @@ phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np)
*/
bool of_dma_is_coherent(struct device_node *np)
{
- struct device_node *node;
+ struct device_node *node __free(device_node) = of_node_get(np);
bool is_coherent = dma_default_coherent;
- node = of_node_get(np);
-
while (node) {
if (of_property_read_bool(node, "dma-coherent")) {
is_coherent = true;
@@ -1032,7 +1013,6 @@ bool of_dma_is_coherent(struct device_node *np)
}
node = of_get_next_dma_parent(node);
}
- of_node_put(node);
return is_coherent;
}
EXPORT_SYMBOL_GPL(of_dma_is_coherent);
@@ -1049,19 +1029,17 @@ EXPORT_SYMBOL_GPL(of_dma_is_coherent);
*/
static bool of_mmio_is_nonposted(struct device_node *np)
{
- struct device_node *parent;
bool nonposted;
if (!IS_ENABLED(CONFIG_ARCH_APPLE))
return false;
- parent = of_get_parent(np);
+ struct device_node *parent __free(device_node) = of_get_parent(np);
if (!parent)
return false;
nonposted = of_property_read_bool(parent, "nonposted-mmio");
- of_node_put(parent);
return nonposted;
}
diff --git a/drivers/of/property.c b/drivers/of/property.c
index a6358ee99b74..b73daf81c99d 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -40,15 +40,12 @@
*/
bool of_graph_is_present(const struct device_node *node)
{
- struct device_node *ports, *port;
+ struct device_node *ports __free(device_node) = of_get_child_by_name(node, "ports");
- ports = of_get_child_by_name(node, "ports");
if (ports)
node = ports;
- port = of_get_child_by_name(node, "port");
- of_node_put(ports);
- of_node_put(port);
+ struct device_node *port __free(device_node) = of_get_child_by_name(node, "port");
return !!port;
}
@@ -610,9 +607,9 @@ EXPORT_SYMBOL(of_graph_parse_endpoint);
*/
struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
{
- struct device_node *node, *port;
+ struct device_node *port;
+ struct device_node *node __free(device_node) = of_get_child_by_name(parent, "ports");
- node = of_get_child_by_name(parent, "ports");
if (node)
parent = node;
@@ -626,8 +623,6 @@ struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
break;
}
- of_node_put(node);
-
return port;
}
EXPORT_SYMBOL(of_graph_get_port_by_id);
@@ -655,14 +650,13 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
* parent port node.
*/
if (!prev) {
- struct device_node *node;
+ struct device_node *node __free(device_node) =
+ of_get_child_by_name(parent, "ports");
- node = of_get_child_by_name(parent, "ports");
if (node)
parent = node;
port = of_get_child_by_name(parent, "port");
- of_node_put(node);
if (!port) {
pr_debug("graph: no port node found in %pOF\n", parent);
@@ -1052,15 +1046,13 @@ static int of_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
struct fwnode_endpoint *endpoint)
{
const struct device_node *node = to_of_node(fwnode);
- struct device_node *port_node = of_get_parent(node);
+ struct device_node *port_node __free(device_node) = of_get_parent(node);
endpoint->local_fwnode = fwnode;
of_property_read_u32(port_node, "reg", &endpoint->port);
of_property_read_u32(node, "reg", &endpoint->id);
- of_node_put(port_node);
-
return 0;
}
--
2.43.0
On Thu, Apr 4, 2024 at 7:15 AM Rob Herring <[email protected]> wrote:
>
> Use the relatively new scope based of_node_put() cleanup to simplify
> function exit handling. Doing so reduces the chances of forgetting an
> of_node_put() and simplifies error paths by avoiding the need for goto
> statements.
>
> Signed-off-by: Rob Herring <[email protected]>
> ---
> drivers/of/address.c | 60 ++++++++++++++++-----------------------------------
> drivers/of/property.c | 22 ++++++-------------
> 2 files changed, 26 insertions(+), 56 deletions(-)
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index ae46a3605904..f7b2d535a6d1 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -491,7 +491,6 @@ static u64 __of_translate_address(struct device_node *dev,
> const __be32 *in_addr, const char *rprop,
> struct device_node **host)
> {
> - struct device_node *parent = NULL;
> struct of_bus *bus, *pbus;
> __be32 addr[OF_MAX_ADDR_CELLS];
> int na, ns, pna, pns;
> @@ -504,7 +503,7 @@ static u64 __of_translate_address(struct device_node *dev,
>
> *host = NULL;
> /* Get parent & match bus type */
> - parent = get_parent(dev);
> + struct device_node *parent __free(device_node) = get_parent(dev);
Can we leave the variable definition where it was? We generally define
all the variables up top. So, defining the one variable in the middle
feels weird. I at least get when we do this inside for/if blocks. But
randomly in the middle feels weird.
Similar comments in other places. Since both kfree() and of_put() can
both handle NULL pointers, I'd be surprised if we HAVE to combine
these lines.
Not a very strong position, but I'd rather we didn't. So,
Reviewed-by: Saravana Kannan <[email protected]>
-Saravana
> if (parent == NULL)
> goto bail;
> bus = of_match_bus(parent);
> @@ -573,7 +572,6 @@ static u64 __of_translate_address(struct device_node *dev,
> of_dump_addr("one level translation:", addr, na);
> }
> bail:
> - of_node_put(parent);
> of_node_put(dev);
>
> return result;
> @@ -654,19 +652,16 @@ EXPORT_SYMBOL(of_translate_dma_address);
> const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop,
> phys_addr_t *start, size_t *length)
> {
> - struct device_node *parent;
> + struct device_node *parent __free(device_node) = __of_get_dma_parent(dev);
> u64 address, size;
> int na, ns;
>
> - parent = __of_get_dma_parent(dev);
> if (!parent)
> return NULL;
>
> na = of_bus_n_addr_cells(parent);
> ns = of_bus_n_size_cells(parent);
>
> - of_node_put(parent);
> -
> address = of_translate_dma_address(dev, prop);
> if (address == OF_BAD_ADDR)
> return NULL;
> @@ -688,21 +683,19 @@ const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no,
> {
> const __be32 *prop;
> unsigned int psize;
> - struct device_node *parent;
> + struct device_node *parent __free(device_node) = of_get_parent(dev);
> struct of_bus *bus;
> int onesize, i, na, ns;
>
> - /* Get parent & match bus type */
> - parent = of_get_parent(dev);
> if (parent == NULL)
> return NULL;
> +
> + /* match the parent's bus type */
> bus = of_match_bus(parent);
> - if (strcmp(bus->name, "pci") && (bar_no >= 0)) {
> - of_node_put(parent);
> + if (strcmp(bus->name, "pci") && (bar_no >= 0))
> return NULL;
> - }
> +
> bus->count_cells(dev, &na, &ns);
> - of_node_put(parent);
> if (!OF_CHECK_ADDR_COUNT(na))
> return NULL;
>
> @@ -888,14 +881,13 @@ static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
> */
> int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
> {
> - struct device_node *node = of_node_get(np);
> + struct device_node *node __free(device_node) = of_node_get(np);
> const __be32 *ranges = NULL;
> bool found_dma_ranges = false;
> struct of_range_parser parser;
> struct of_range range;
> struct bus_dma_region *r;
> int len, num_ranges = 0;
> - int ret = 0;
>
> while (node) {
> ranges = of_get_property(node, "dma-ranges", &len);
> @@ -905,10 +897,9 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
> break;
>
> /* Once we find 'dma-ranges', then a missing one is an error */
> - if (found_dma_ranges && !ranges) {
> - ret = -ENODEV;
> - goto out;
> - }
> + if (found_dma_ranges && !ranges)
> + return -ENODEV;
> +
> found_dma_ranges = true;
>
> node = of_get_next_dma_parent(node);
> @@ -916,10 +907,8 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
>
> if (!node || !ranges) {
> pr_debug("no dma-ranges found for node(%pOF)\n", np);
> - ret = -ENODEV;
> - goto out;
> + return -ENODEV;
> }
> -
> of_dma_range_parser_init(&parser, node);
> for_each_of_range(&parser, &range) {
> if (range.cpu_addr == OF_BAD_ADDR) {
> @@ -930,16 +919,12 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
> num_ranges++;
> }
>
> - if (!num_ranges) {
> - ret = -EINVAL;
> - goto out;
> - }
> + if (!num_ranges)
> + return -EINVAL;
>
> r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
> - if (!r) {
> - ret = -ENOMEM;
> - goto out;
> - }
> + if (!r)
> + return -ENOMEM;
>
> /*
> * Record all info in the generic DMA ranges array for struct device,
> @@ -957,9 +942,7 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
> r->size = range.size;
> r++;
> }
> -out:
> - of_node_put(node);
> - return ret;
> + return 0;
> }
> #endif /* CONFIG_HAS_DMA */
>
> @@ -1016,11 +999,9 @@ phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np)
> */
> bool of_dma_is_coherent(struct device_node *np)
> {
> - struct device_node *node;
> + struct device_node *node __free(device_node) = of_node_get(np);
> bool is_coherent = dma_default_coherent;
>
> - node = of_node_get(np);
> -
> while (node) {
> if (of_property_read_bool(node, "dma-coherent")) {
> is_coherent = true;
> @@ -1032,7 +1013,6 @@ bool of_dma_is_coherent(struct device_node *np)
> }
> node = of_get_next_dma_parent(node);
> }
> - of_node_put(node);
> return is_coherent;
> }
> EXPORT_SYMBOL_GPL(of_dma_is_coherent);
> @@ -1049,19 +1029,17 @@ EXPORT_SYMBOL_GPL(of_dma_is_coherent);
> */
> static bool of_mmio_is_nonposted(struct device_node *np)
> {
> - struct device_node *parent;
> bool nonposted;
>
> if (!IS_ENABLED(CONFIG_ARCH_APPLE))
> return false;
>
> - parent = of_get_parent(np);
> + struct device_node *parent __free(device_node) = of_get_parent(np);
> if (!parent)
> return false;
>
> nonposted = of_property_read_bool(parent, "nonposted-mmio");
>
> - of_node_put(parent);
> return nonposted;
> }
>
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index a6358ee99b74..b73daf81c99d 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -40,15 +40,12 @@
> */
> bool of_graph_is_present(const struct device_node *node)
> {
> - struct device_node *ports, *port;
> + struct device_node *ports __free(device_node) = of_get_child_by_name(node, "ports");
>
> - ports = of_get_child_by_name(node, "ports");
> if (ports)
> node = ports;
>
> - port = of_get_child_by_name(node, "port");
> - of_node_put(ports);
> - of_node_put(port);
> + struct device_node *port __free(device_node) = of_get_child_by_name(node, "port");
>
> return !!port;
> }
> @@ -610,9 +607,9 @@ EXPORT_SYMBOL(of_graph_parse_endpoint);
> */
> struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
> {
> - struct device_node *node, *port;
> + struct device_node *port;
> + struct device_node *node __free(device_node) = of_get_child_by_name(parent, "ports");
>
> - node = of_get_child_by_name(parent, "ports");
> if (node)
> parent = node;
>
> @@ -626,8 +623,6 @@ struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
> break;
> }
>
> - of_node_put(node);
> -
> return port;
> }
> EXPORT_SYMBOL(of_graph_get_port_by_id);
> @@ -655,14 +650,13 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
> * parent port node.
> */
> if (!prev) {
> - struct device_node *node;
> + struct device_node *node __free(device_node) =
> + of_get_child_by_name(parent, "ports");
>
> - node = of_get_child_by_name(parent, "ports");
> if (node)
> parent = node;
>
> port = of_get_child_by_name(parent, "port");
> - of_node_put(node);
>
> if (!port) {
> pr_debug("graph: no port node found in %pOF\n", parent);
> @@ -1052,15 +1046,13 @@ static int of_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
> struct fwnode_endpoint *endpoint)
> {
> const struct device_node *node = to_of_node(fwnode);
> - struct device_node *port_node = of_get_parent(node);
> + struct device_node *port_node __free(device_node) = of_get_parent(node);
>
> endpoint->local_fwnode = fwnode;
>
> of_property_read_u32(port_node, "reg", &endpoint->port);
> of_property_read_u32(node, "reg", &endpoint->id);
>
> - of_node_put(port_node);
> -
> return 0;
> }
>
>
> --
> 2.43.0
>
On Thu, Apr 4, 2024 at 6:22 PM Saravana Kannan <[email protected]> wrote:
>
> On Thu, Apr 4, 2024 at 7:15 AM Rob Herring <[email protected]> wrote:
> >
> > Use the relatively new scope based of_node_put() cleanup to simplify
> > function exit handling. Doing so reduces the chances of forgetting an
> > of_node_put() and simplifies error paths by avoiding the need for goto
> > statements.
> >
> > Signed-off-by: Rob Herring <[email protected]>
> > ---
> > drivers/of/address.c | 60 ++++++++++++++++-----------------------------------
> > drivers/of/property.c | 22 ++++++-------------
> > 2 files changed, 26 insertions(+), 56 deletions(-)
> >
> > diff --git a/drivers/of/address.c b/drivers/of/address.c
> > index ae46a3605904..f7b2d535a6d1 100644
> > --- a/drivers/of/address.c
> > +++ b/drivers/of/address.c
> > @@ -491,7 +491,6 @@ static u64 __of_translate_address(struct device_node *dev,
> > const __be32 *in_addr, const char *rprop,
> > struct device_node **host)
> > {
> > - struct device_node *parent = NULL;
> > struct of_bus *bus, *pbus;
> > __be32 addr[OF_MAX_ADDR_CELLS];
> > int na, ns, pna, pns;
> > @@ -504,7 +503,7 @@ static u64 __of_translate_address(struct device_node *dev,
> >
> > *host = NULL;
> > /* Get parent & match bus type */
> > - parent = get_parent(dev);
> > + struct device_node *parent __free(device_node) = get_parent(dev);
>
> Can we leave the variable definition where it was? We generally define
> all the variables up top. So, defining the one variable in the middle
> feels weird. I at least get when we do this inside for/if blocks. But
> randomly in the middle feels weird.
There's an 'of_node_get(dev);' before this. Ordering wise, we need to
hold the ref on the child before we get its parent. I suppose I can
also convert that to use the cleanups. I'll have to add another local
ptr to do that though.
>
> Similar comments in other places. Since both kfree() and of_put() can
> both handle NULL pointers, I'd be surprised if we HAVE to combine
> these lines.
https://lore.kernel.org/all/CAHk-=wgRHiV5VSxtfXA4S6aLUmcQYEuB67u3BJPJPtuESs1JyA@mail.gmail.com/
On Fri, Apr 5, 2024 at 6:01 AM Rob Herring <[email protected]> wrote:
>
> On Thu, Apr 4, 2024 at 6:22 PM Saravana Kannan <[email protected]> wrote:
> >
> > On Thu, Apr 4, 2024 at 7:15 AM Rob Herring <[email protected]> wrote:
> > >
> > > Use the relatively new scope based of_node_put() cleanup to simplify
> > > function exit handling. Doing so reduces the chances of forgetting an
> > > of_node_put() and simplifies error paths by avoiding the need for goto
> > > statements.
> > >
> > > Signed-off-by: Rob Herring <[email protected]>
> > > ---
> > > drivers/of/address.c | 60 ++++++++++++++++-----------------------------------
> > > drivers/of/property.c | 22 ++++++-------------
> > > 2 files changed, 26 insertions(+), 56 deletions(-)
> > >
> > > diff --git a/drivers/of/address.c b/drivers/of/address.c
> > > index ae46a3605904..f7b2d535a6d1 100644
> > > --- a/drivers/of/address.c
> > > +++ b/drivers/of/address.c
> > > @@ -491,7 +491,6 @@ static u64 __of_translate_address(struct device_node *dev,
> > > const __be32 *in_addr, const char *rprop,
> > > struct device_node **host)
> > > {
> > > - struct device_node *parent = NULL;
> > > struct of_bus *bus, *pbus;
> > > __be32 addr[OF_MAX_ADDR_CELLS];
> > > int na, ns, pna, pns;
> > > @@ -504,7 +503,7 @@ static u64 __of_translate_address(struct device_node *dev,
> > >
> > > *host = NULL;
> > > /* Get parent & match bus type */
> > > - parent = get_parent(dev);
> > > + struct device_node *parent __free(device_node) = get_parent(dev);
> >
> > Can we leave the variable definition where it was? We generally define
> > all the variables up top. So, defining the one variable in the middle
> > feels weird. I at least get when we do this inside for/if blocks. But
> > randomly in the middle feels weird.
>
> There's an 'of_node_get(dev);' before this. Ordering wise, we need to
> hold the ref on the child before we get its parent. I suppose I can
> also convert that to use the cleanups. I'll have to add another local
> ptr to do that though.
>
> >
> > Similar comments in other places. Since both kfree() and of_put() can
> > both handle NULL pointers, I'd be surprised if we HAVE to combine
> > these lines.
>
> https://lore.kernel.org/all/CAHk-=wgRHiV5VSxtfXA4S6aLUmcQYEuB67u3BJPJPtuESs1JyA@mail.gmail.com/
Review-by without reservations.
-Saravana
On Thu, 04 Apr 2024 09:15:12 -0500
Rob Herring <[email protected]> wrote:
> Use the relatively new scope based of_node_put() cleanup to simplify
> function exit handling. Doing so reduces the chances of forgetting an
> of_node_put() and simplifies error paths by avoiding the need for goto
> statements.
>
> Signed-off-by: Rob Herring <[email protected]>
Hi Rob,
Looks good in general. A few suggestions inline.
First one is a little more complex, but I think will give you a better end result
The others are readability improvements enabled by the changes you've made
that I think you could validly change in this same patch.
Jonathan
> ---
> drivers/of/address.c | 60 ++++++++++++++++-----------------------------------
> drivers/of/property.c | 22 ++++++-------------
> 2 files changed, 26 insertions(+), 56 deletions(-)
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index ae46a3605904..f7b2d535a6d1 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -491,7 +491,6 @@ static u64 __of_translate_address(struct device_node *dev,
> const __be32 *in_addr, const char *rprop,
> struct device_node **host)
> {
> - struct device_node *parent = NULL;
> struct of_bus *bus, *pbus;
> __be32 addr[OF_MAX_ADDR_CELLS];
> int na, ns, pna, pns;
> @@ -504,7 +503,7 @@ static u64 __of_translate_address(struct device_node *dev,
>
> *host = NULL;
> /* Get parent & match bus type */
> - parent = get_parent(dev);
> + struct device_node *parent __free(device_node) = get_parent(dev);
This is an order change as we'll put this node after dev
Whilst probably fine, I'd call that out in the patch description or just throw
in an earlier
struct device_node *dev_node __free(device_node) = of_node_get(dev);
Obviously the release order doesn't actually matter but a reader has to think
about it briefly to be sure.
Bonus if you do that is that you get to do direct returns at the error condition
and potentially in the breaks out of the loop. To my eye that's a readability
advantage.
In at least one place you could also steal the pointer rather than
getting another reference to dev (taking it to at least 2) then dropping
one of them in the exit path. Can use no_free_ptr() for that.
From readability point of view you'd only want to do that with a direct return.
*host = no_free_ptr(dev_node);
return result;
}
> if (parent == NULL)
> goto bail;
> bus = of_match_bus(parent);
> @@ -573,7 +572,6 @@ static u64 __of_translate_address(struct device_node *dev,
> of_dump_addr("one level translation:", addr, na);
> }
> bail:
> - of_node_put(parent);
> of_node_put(dev);
>
> @@ -1016,11 +999,9 @@ phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np)
> */
> bool of_dma_is_coherent(struct device_node *np)
> {
> - struct device_node *node;
> + struct device_node *node __free(device_node) = of_node_get(np);
> bool is_coherent = dma_default_coherent;
>
> - node = of_node_get(np);
> -
> while (node) {
> if (of_property_read_bool(node, "dma-coherent")) {
> is_coherent = true;
return true;
and same in the other branch given you break out the loop and return it directly.
> @@ -1032,7 +1013,6 @@ bool of_dma_is_coherent(struct device_node *np)
> }
> node = of_get_next_dma_parent(node);
> }
> - of_node_put(node);
> return is_coherent;
With above early returns
return dma_default_coherent;
and drop the is_coherent variable as no longer used.
This sort of related cleanup is one reason I really like the cleanup.h magic.
> }
> EXPORT_SYMBOL_GPL(of_dma_is_coherent);
> @@ -1049,19 +1029,17 @@ EXPORT_SYMBOL_GPL(of_dma_is_coherent);
> */
> static bool of_mmio_is_nonposted(struct device_node *np)
> {
> - struct device_node *parent;
> bool nonposted;
>
> if (!IS_ENABLED(CONFIG_ARCH_APPLE))
> return false;
>
> - parent = of_get_parent(np);
> + struct device_node *parent __free(device_node) = of_get_parent(np);
> if (!parent)
> return false;
>
> nonposted = of_property_read_bool(parent, "nonposted-mmio");
>
> - of_node_put(parent);
> return nonposted;
return of_property_read_bool()
> }
>