diff mbox series

[v3,2/4] block: partitions: populate fwnode

Message ID afa870ec6ac1027561d1c002205ab1e05358a46c.1719368448.git.daniel@makrotopia.org (mailing list archive)
State Superseded
Headers show
Series block: preparations for NVMEM provider | expand

Commit Message

Daniel Golle June 26, 2024, 2:50 a.m. UTC 
Let block partitions to be represented by a firmware node and hence
allow them to being referenced e.g. for use with blk-nvmem.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
 block/partitions/core.c | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

Comments

Jens Axboe June 26, 2024, 7:43 p.m. UTC | #1 
On 6/25/24 8:50 PM, Daniel Golle wrote:
> diff --git a/block/partitions/core.c b/block/partitions/core.c
> index ab76e64f0f6c..f88829e254e6 100644
> --- a/block/partitions/core.c
> +++ b/block/partitions/core.c
> @@ -10,6 +10,8 @@
>  #include <linux/ctype.h>
>  #include <linux/vmalloc.h>
>  #include <linux/raid/detect.h>
> +#include <linux/property.h>
> +
>  #include "check.h"
>  
>  static int (*const check_part[])(struct parsed_partitions *) = {
> @@ -281,6 +283,42 @@ static ssize_t whole_disk_show(struct device *dev,
>  }
>  static const DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL);
>  
> +static struct fwnode_handle *find_partition_fwnode(struct block_device *bdev)
> +{
> +	struct fwnode_handle *fw_parts, *fw_part;
> +	struct device *ddev = disk_to_dev(bdev->bd_disk);
> +	const char *partname, *uuid;
> +	u32 partno;
> +
> +	fw_parts = device_get_named_child_node(ddev, "partitions");
> +	if (!fw_parts)
> +		fw_parts = device_get_named_child_node(ddev->parent, "partitions");
> +
> +	if (!fw_parts)
> +		return NULL;

That last if check should to inside the previous one.

> +	fwnode_for_each_child_node(fw_parts, fw_part) {
> +		if (!fwnode_property_read_string(fw_part, "uuid", &uuid) &&
> +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_UUIDLTH ||
> +		     strncmp(uuid, bdev->bd_meta_info->uuid, PARTITION_META_INFO_UUIDLTH)))
> +			continue;
> +
> +		if (!fwnode_property_read_string(fw_part, "partname", &partname) &&
> +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_VOLNAMELTH ||
> +		     strncmp(partname, bdev->bd_meta_info->volname,
> +			     PARTITION_META_INFO_VOLNAMELTH)))
> +			continue;

This is pretty hard to make sense of...
Daniel Golle June 26, 2024, 7:58 p.m. UTC | #2 
On Wed, Jun 26, 2024 at 01:43:49PM -0600, Jens Axboe wrote:
> On 6/25/24 8:50 PM, Daniel Golle wrote:
> > diff --git a/block/partitions/core.c b/block/partitions/core.c
> > index ab76e64f0f6c..f88829e254e6 100644
> > --- a/block/partitions/core.c
> > +++ b/block/partitions/core.c
> > @@ -10,6 +10,8 @@
> >  #include <linux/ctype.h>
> >  #include <linux/vmalloc.h>
> >  #include <linux/raid/detect.h>
> > +#include <linux/property.h>
> > +
> >  #include "check.h"
> >  
> >  static int (*const check_part[])(struct parsed_partitions *) = {
> > @@ -281,6 +283,42 @@ static ssize_t whole_disk_show(struct device *dev,
> >  }
> >  static const DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL);
> >  
> > +static struct fwnode_handle *find_partition_fwnode(struct block_device *bdev)
> > +{
> > +	struct fwnode_handle *fw_parts, *fw_part;
> > +	struct device *ddev = disk_to_dev(bdev->bd_disk);
> > +	const char *partname, *uuid;
> > +	u32 partno;
> > +
> > +	fw_parts = device_get_named_child_node(ddev, "partitions");
> > +	if (!fw_parts)
> > +		fw_parts = device_get_named_child_node(ddev->parent, "partitions");
> > +
> > +	if (!fw_parts)
> > +		return NULL;
> 
> That last if check should to inside the previous one.

Actually the previous one should have been removed entirely. I somehow
forgot to 'git add' that change.

> 
> > +	fwnode_for_each_child_node(fw_parts, fw_part) {
> > +		if (!fwnode_property_read_string(fw_part, "uuid", &uuid) &&
> > +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_UUIDLTH ||
> > +		     strncmp(uuid, bdev->bd_meta_info->uuid, PARTITION_META_INFO_UUIDLTH)))
> > +			continue;
> > +
> > +		if (!fwnode_property_read_string(fw_part, "partname", &partname) &&
> > +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_VOLNAMELTH ||
> > +		     strncmp(partname, bdev->bd_meta_info->volname,
> > +			     PARTITION_META_INFO_VOLNAMELTH)))
> > +			continue;
> 
> This is pretty hard to make sense of...

I'll add comments explaining it. Or should I use another syntax, e.g. several
nested if-clauses, instead?
Jens Axboe June 26, 2024, 8:09 p.m. UTC | #3 
On 6/26/24 1:58 PM, Daniel Golle wrote:
> On Wed, Jun 26, 2024 at 01:43:49PM -0600, Jens Axboe wrote:
>> On 6/25/24 8:50 PM, Daniel Golle wrote:
>>> diff --git a/block/partitions/core.c b/block/partitions/core.c
>>> index ab76e64f0f6c..f88829e254e6 100644
>>> --- a/block/partitions/core.c
>>> +++ b/block/partitions/core.c
>>> @@ -10,6 +10,8 @@
>>>  #include <linux/ctype.h>
>>>  #include <linux/vmalloc.h>
>>>  #include <linux/raid/detect.h>
>>> +#include <linux/property.h>
>>> +
>>>  #include "check.h"
>>>  
>>>  static int (*const check_part[])(struct parsed_partitions *) = {
>>> @@ -281,6 +283,42 @@ static ssize_t whole_disk_show(struct device *dev,
>>>  }
>>>  static const DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL);
>>>  
>>> +static struct fwnode_handle *find_partition_fwnode(struct block_device *bdev)
>>> +{
>>> +	struct fwnode_handle *fw_parts, *fw_part;
>>> +	struct device *ddev = disk_to_dev(bdev->bd_disk);
>>> +	const char *partname, *uuid;
>>> +	u32 partno;
>>> +
>>> +	fw_parts = device_get_named_child_node(ddev, "partitions");
>>> +	if (!fw_parts)
>>> +		fw_parts = device_get_named_child_node(ddev->parent, "partitions");
>>> +
>>> +	if (!fw_parts)
>>> +		return NULL;
>>
>> That last if check should to inside the previous one.
> 
> Actually the previous one should have been removed entirely. I somehow
> forgot to 'git add' that change.
> 
>>
>>> +	fwnode_for_each_child_node(fw_parts, fw_part) {
>>> +		if (!fwnode_property_read_string(fw_part, "uuid", &uuid) &&
>>> +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_UUIDLTH ||
>>> +		     strncmp(uuid, bdev->bd_meta_info->uuid, PARTITION_META_INFO_UUIDLTH)))
>>> +			continue;
>>> +
>>> +		if (!fwnode_property_read_string(fw_part, "partname", &partname) &&
>>> +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_VOLNAMELTH ||
>>> +		     strncmp(partname, bdev->bd_meta_info->volname,
>>> +			     PARTITION_META_INFO_VOLNAMELTH)))
>>> +			continue;
>>
>> This is pretty hard to make sense of...
> 
> I'll add comments explaining it. Or should I use another syntax, e.g. several
> nested if-clauses, instead?

Maybe some kind of helpers for these instead, with comments? Nobody can
read the above.
diff mbox series

Patch

diff --git a/block/partitions/core.c b/block/partitions/core.c
index ab76e64f0f6c..f88829e254e6 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -10,6 +10,8 @@ 
 #include <linux/ctype.h>
 #include <linux/vmalloc.h>
 #include <linux/raid/detect.h>
+#include <linux/property.h>
+
 #include "check.h"
 
 static int (*const check_part[])(struct parsed_partitions *) = {
@@ -281,6 +283,42 @@  static ssize_t whole_disk_show(struct device *dev,
 }
 static const DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL);
 
+static struct fwnode_handle *find_partition_fwnode(struct block_device *bdev)
+{
+	struct fwnode_handle *fw_parts, *fw_part;
+	struct device *ddev = disk_to_dev(bdev->bd_disk);
+	const char *partname, *uuid;
+	u32 partno;
+
+	fw_parts = device_get_named_child_node(ddev, "partitions");
+	if (!fw_parts)
+		fw_parts = device_get_named_child_node(ddev->parent, "partitions");
+
+	if (!fw_parts)
+		return NULL;
+
+	fwnode_for_each_child_node(fw_parts, fw_part) {
+		if (!fwnode_property_read_string(fw_part, "uuid", &uuid) &&
+		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_UUIDLTH ||
+		     strncmp(uuid, bdev->bd_meta_info->uuid, PARTITION_META_INFO_UUIDLTH)))
+			continue;
+
+		if (!fwnode_property_read_string(fw_part, "partname", &partname) &&
+		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_VOLNAMELTH ||
+		     strncmp(partname, bdev->bd_meta_info->volname,
+			     PARTITION_META_INFO_VOLNAMELTH)))
+			continue;
+
+		if (!fwnode_property_read_u32(fw_part, "partno", &partno) &&
+		    bdev_partno(bdev) != partno)
+			continue;
+
+		return fw_part;
+	}
+
+	return NULL;
+}
+
 /*
  * Must be called either with open_mutex held, before a disk can be opened or
  * after all disk users are gone.
@@ -355,6 +393,8 @@  static struct block_device *add_partition(struct gendisk *disk, int partno,
 			goto out_put;
 	}
 
+	device_set_node(pdev, find_partition_fwnode(bdev));
+
 	/* delay uevent until 'holders' subdir is created */
 	dev_set_uevent_suppress(pdev, 1);
 	err = device_add(pdev);