Commit 0f423895 authored by James Bottomley's avatar James Bottomley
Browse files

[SCSI] sysfs: make group is_valid return a mode_t 



We have a problem in scsi_transport_spi in that we need to customise
not only the visibility of the attributes, but also their mode.  Fix
this by making the is_visible() callback return a mode, with 0
indicating is not visible.

Also add a sysfs_update_group() API to allow us to change either the
visibility or mode of the files at any time on the fly.

Acked-by: default avatarKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
parent bbd1ae41

fs/sysfs/file.c

+10 −4
Original line number Diff line number Diff line
@@ -477,11 +477,10 @@ const struct file_operations sysfs_file_operations = { 
	.poll		= sysfs_poll,

};





int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr,

		   int type)

int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,

			const struct attribute *attr, int type, mode_t amode)

{

	umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;

	umode_t mode = (amode & S_IALLUGO) | S_IFREG;

	struct sysfs_addrm_cxt acxt;

	struct sysfs_dirent *sd;

	int rc;
@@ -502,6 +501,13 @@ int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr, 
}





int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr,

		   int type)

{

	return sysfs_add_file_mode(dir_sd, attr, type, attr->mode);

}





/**

 *	sysfs_create_file - create an attribute file for an object.

 *	@kobj:	object we're creating for.

fs/sysfs/group.c

+70 −13
Original line number Diff line number Diff line
@@ -23,35 +23,50 @@ static void remove_files(struct sysfs_dirent *dir_sd, struct kobject *kobj, 
	int i;



	for (i = 0, attr = grp->attrs; *attr; i++, attr++)

		if (!grp->is_visible ||

		    grp->is_visible(kobj, *attr, i))

		sysfs_hash_and_remove(dir_sd, (*attr)->name);

}



static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,

			const struct attribute_group *grp)

			const struct attribute_group *grp, int update)

{

	struct attribute *const* attr;

	int error = 0, i;



	for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++)

		if (!grp->is_visible ||

		    grp->is_visible(kobj, *attr, i))

			error |=

				sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR);

	for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) {

		mode_t mode = 0;



		/* in update mode, we're changing the permissions or

		 * visibility.  Do this by first removing then

		 * re-adding (if required) the file */

		if (update)

			sysfs_hash_and_remove(dir_sd, (*attr)->name);

		if (grp->is_visible) {

			mode = grp->is_visible(kobj, *attr, i);

			if (!mode)

				continue;

		}

		error = sysfs_add_file_mode(dir_sd, *attr, SYSFS_KOBJ_ATTR,

					    (*attr)->mode | mode);

		if (unlikely(error))

			break;

	}

	if (error)

		remove_files(dir_sd, kobj, grp);

	return error;

}





int sysfs_create_group(struct kobject * kobj, 

static int internal_create_group(struct kobject *kobj, int update,

				 const struct attribute_group *grp)

{

	struct sysfs_dirent *sd;

	int error;



	BUG_ON(!kobj || !kobj->sd);

	BUG_ON(!kobj || (!update && !kobj->sd));



	/* Updates may happen before the object has been instantiated */

	if (unlikely(update && !kobj->sd))

		return -EINVAL;



	if (grp->name) {

		error = sysfs_create_subdir(kobj, grp->name, &sd);
@@ -60,7 +75,7 @@ int sysfs_create_group(struct kobject * kobj, 
	} else

		sd = kobj->sd;

	sysfs_get(sd);

	error = create_files(sd, kobj, grp);

	error = create_files(sd, kobj, grp, update);

	if (error) {

		if (grp->name)

			sysfs_remove_subdir(sd);
@@ -69,6 +84,47 @@ int sysfs_create_group(struct kobject * kobj, 
	return error;

}



/**

 * sysfs_create_group - given a directory kobject, create an attribute group

 * @kobj:	The kobject to create the group on

 * @grp:	The attribute group to create

 *

 * This function creates a group for the first time.  It will explicitly

 * warn and error if any of the attribute files being created already exist.

 *

 * Returns 0 on success or error.

 */

int sysfs_create_group(struct kobject *kobj,

		       const struct attribute_group *grp)

{

	return internal_create_group(kobj, 0, grp);

}



/**

 * sysfs_update_group - given a directory kobject, create an attribute group

 * @kobj:	The kobject to create the group on

 * @grp:	The attribute group to create

 *

 * This function updates an attribute group.  Unlike

 * sysfs_create_group(), it will explicitly not warn or error if any

 * of the attribute files being created already exist.  Furthermore,

 * if the visibility of the files has changed through the is_visible()

 * callback, it will update the permissions and add or remove the

 * relevant files.

 *

 * The primary use for this function is to call it after making a change

 * that affects group visibility.

 *

 * Returns 0 on success or error.

 */

int sysfs_update_group(struct kobject *kobj,

		       const struct attribute_group *grp)

{

	return internal_create_group(kobj, 1, grp);

}







void sysfs_remove_group(struct kobject * kobj, 

			const struct attribute_group * grp)

{
@@ -95,4 +151,5 @@ void sysfs_remove_group(struct kobject * kobj, 




EXPORT_SYMBOL_GPL(sysfs_create_group);

EXPORT_SYMBOL_GPL(sysfs_update_group);

EXPORT_SYMBOL_GPL(sysfs_remove_group);

fs/sysfs/sysfs.h

+2 −0
Original line number Diff line number Diff line
@@ -154,6 +154,8 @@ extern const struct file_operations sysfs_file_operations; 
int sysfs_add_file(struct sysfs_dirent *dir_sd,

		   const struct attribute *attr, int type);



int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,

			const struct attribute *attr, int type, mode_t amode);

/*

 * bin.c

 */

include/linux/sysfs.h

+3 −1
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ struct attribute { 


struct attribute_group {

	const char		*name;

	int			(*is_visible)(struct kobject *,

	mode_t			(*is_visible)(struct kobject *,

					      struct attribute *, int);

	struct attribute	**attrs;

};
@@ -105,6 +105,8 @@ void sysfs_remove_link(struct kobject *kobj, const char *name); 


int __must_check sysfs_create_group(struct kobject *kobj,

				    const struct attribute_group *grp);

int sysfs_update_group(struct kobject *kobj,

		       const struct attribute_group *grp);

void sysfs_remove_group(struct kobject *kobj,

			const struct attribute_group *grp);

int sysfs_add_file_to_group(struct kobject *kobj,

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