Commit 56b3f3b8 authored by Tejun Heo's avatar Tejun Heo Committed by Greg Kroah-Hartman
Browse files

sysfs: merge sysfs_elem_bin_attr into sysfs_elem_attr 



3124eb16 ("sysfs: merge regular and bin file handling") folded bin
file handling into regular file handling.  Among other things, bin
file now shares the same open path including sysfs_open_dirent
association using sysfs_dirent->s_attr.open.  This is buggy because
->s_bin_attr lives in the same union and doesn't have the field.  This
bug doesn't trigger because sysfs_elem_bin_attr doesn't have an active
field at the conflicting position.  It does have a field "buffers" but
it isn't used anymore.

This patch collapses sysfs_elem_bin_attr into sysfs_elem_attr so that
the bin_attr is accessed through ->s_attr.bin_attr which lives with
->s_attr.attr in an anonymous union.  The code paths already assume
bin_attr contains attr as the first element, so this doesn't add any
more assumptions while making it explicit that the two types are
handled together.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 6fffcfa7

fs/sysfs/file.c

+4 −4
Original line number Diff line number Diff line
@@ -154,7 +154,7 @@ static ssize_t sysfs_bin_read(struct file *file, char __user *userbuf, 
			      size_t bytes, loff_t *off)

{

	struct sysfs_open_file *of = sysfs_of(file);

	struct bin_attribute *battr = of->sd->s_bin_attr.bin_attr;

	struct bin_attribute *battr = of->sd->s_attr.bin_attr;

	struct kobject *kobj = of->sd->s_parent->s_dir.kobj;

	loff_t size = file_inode(file)->i_size;

	int count = min_t(size_t, bytes, PAGE_SIZE);
@@ -236,7 +236,7 @@ static int flush_write_buffer(struct sysfs_open_file *of, char *buf, loff_t off, 
	}



	if (sysfs_is_bin(of->sd)) {

		struct bin_attribute *battr = of->sd->s_bin_attr.bin_attr;

		struct bin_attribute *battr = of->sd->s_attr.bin_attr;



		rc = -EIO;

		if (battr->write)
@@ -466,7 +466,7 @@ static const struct vm_operations_struct sysfs_bin_vm_ops = { 
static int sysfs_bin_mmap(struct file *file, struct vm_area_struct *vma)

{

	struct sysfs_open_file *of = sysfs_of(file);

	struct bin_attribute *battr = of->sd->s_bin_attr.bin_attr;

	struct bin_attribute *battr = of->sd->s_attr.bin_attr;

	struct kobject *kobj = of->sd->s_parent->s_dir.kobj;

	int rc;
@@ -618,7 +618,7 @@ static int sysfs_open_file(struct inode *inode, struct file *file) 
		return -ENODEV;



	if (sysfs_is_bin(attr_sd)) {

		struct bin_attribute *battr = attr_sd->s_bin_attr.bin_attr;

		struct bin_attribute *battr = attr_sd->s_attr.bin_attr;



		has_read = battr->read || battr->mmap;

		has_write = battr->write || battr->mmap;

fs/sysfs/inode.c

+1 −1
Original line number Diff line number Diff line
@@ -258,7 +258,7 @@ static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) 
		inode->i_fop = &sysfs_file_operations;

		break;

	case SYSFS_KOBJ_BIN_ATTR:

		bin_attr = sd->s_bin_attr.bin_attr;

		bin_attr = sd->s_attr.bin_attr;

		inode->i_size = bin_attr->size;

		inode->i_fop = &sysfs_bin_operations;

		break;

fs/sysfs/sysfs.h

+4 −7
Original line number Diff line number Diff line
@@ -29,13 +29,11 @@ struct sysfs_elem_symlink { 
};



struct sysfs_elem_attr {

	union {

		struct attribute	*attr;

	struct sysfs_open_dirent *open;

};



struct sysfs_elem_bin_attr {

		struct bin_attribute	*bin_attr;

	struct hlist_head	buffers;

	};

	struct sysfs_open_dirent *open;

};



struct sysfs_inode_attrs {
@@ -74,7 +72,6 @@ struct sysfs_dirent { 
		struct sysfs_elem_dir		s_dir;

		struct sysfs_elem_symlink	s_symlink;

		struct sysfs_elem_attr		s_attr;

		struct sysfs_elem_bin_attr	s_bin_attr;

	};



	unsigned short		s_flags;

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