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(+)
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);
--
2.45.2On 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...
--
Jens Axboe
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?
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.
--
Jens Axboe
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