Commit 471bd7b7 authored by Tejun Heo's avatar Tejun Heo Committed by Greg Kroah-Hartman
Browse files

sysfs, kernfs: add sysfs_dirent->s_attr.size 



sysfs sets the size of regular files unconditionally at PAGE_SIZE and
takes the size of bin files from bin_attribute.  The latter is a
pretty bad interface which forces bin_attribute users to create a
separate copy of bin_attribute for each instance of the file -
e.g. pci resource files.

Add sysfs_dirent->s_attr.size so that the size can be specified
separately.  This unifies inode init paths of ATTR and BIN_ATTR
identical and allows for generic size handling for kernfs.

Unfortunately, this grows the size of sysfs_dirent by sizeof(loff_t).

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f6acf8bb

fs/sysfs/file.c

+6 −0
Original line number Diff line number Diff line
@@ -923,6 +923,7 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd, 
	const struct kernfs_ops *ops;

	struct sysfs_addrm_cxt acxt;

	struct sysfs_dirent *sd;

	loff_t size;

	int rc;



	if (type == SYSFS_KOBJ_ATTR) {
@@ -943,6 +944,8 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd, 
			ops = &sysfs_file_kfops_wo;

		else

			ops = &sysfs_file_kfops_empty;



		size = PAGE_SIZE;

	} else {

		struct bin_attribute *battr = (void *)attr;
@@ -954,6 +957,8 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd, 
			ops = &sysfs_bin_kfops_wo;

		else

			ops = &sysfs_file_kfops_empty;



		size = battr->size;

	}



	sd = sysfs_new_dirent(attr->name, mode, type);
@@ -961,6 +966,7 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd, 
		return -ENOMEM;



	sd->s_attr.ops = ops;

	sd->s_attr.size = size;

	sd->s_ns = ns;

	sd->priv = (void *)attr;

	sysfs_dirent_init_lockdep(sd);

fs/sysfs/inode.c

+1 −7
Original line number Diff line number Diff line
@@ -254,8 +254,6 @@ int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, 


static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)

{

	struct bin_attribute *bin_attr;



	inode->i_private = sysfs_get(sd);

	inode->i_mapping->a_ops = &sysfs_aops;

	inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
@@ -271,12 +269,8 @@ static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) 
		inode->i_fop = &sysfs_dir_operations;

		break;

	case SYSFS_KOBJ_ATTR:

		inode->i_size = PAGE_SIZE;

		inode->i_fop = &kernfs_file_operations;

		break;

	case SYSFS_KOBJ_BIN_ATTR:

		bin_attr = sd->priv;

		inode->i_size = bin_attr->size;

		inode->i_size = sd->s_attr.size;

		inode->i_fop = &kernfs_file_operations;

		break;

	case SYSFS_KOBJ_LINK:

fs/sysfs/sysfs.h

+1 −0
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ struct sysfs_elem_symlink { 
struct sysfs_elem_attr {

	const struct kernfs_ops	*ops;

	struct sysfs_open_dirent *open;

	loff_t			size;

};



struct sysfs_inode_attrs {

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