Commit 3ca5999f authored by Patrick Mochel's avatar Patrick Mochel

sysfs: further localize file creation.

- reanme sysfs_get_inode() to sysfs_create().
- Assume we're using the single sysfs superblock when creating something.
- move file object-specific init commands to callbacks.
- streamline file and directory creation to remove duplicate checks.
- clean up sysfs_fill_super() a bit. 
parent f7a5d012
......@@ -10,16 +10,15 @@
#include <linux/kobject.h>
#include "sysfs.h"
static int sysfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
static int init_dir(struct inode * inode)
{
int res;
mode = (mode & (S_IRWXUGO|S_ISVTX)) | S_IFDIR;
res = sysfs_mknod(dir, dentry, mode, 0);
if (!res)
dir->i_nlink++;
return res;
}
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inode->i_nlink++;
return 0;
}
/**
* sysfs_create_dir - create a directory for an object.
......@@ -48,8 +47,10 @@ int sysfs_create_dir(struct kobject * kobj)
if (!IS_ERR(dentry)) {
dentry->d_fsdata = (void *)kobj;
kobj->dentry = dentry;
error = sysfs_mkdir(parent->d_inode,dentry,
(S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO));
error = sysfs_create(dentry,(S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO),
init_dir);
if (!error)
parent->d_inode->i_nlink++;
} else
error = PTR_ERR(dentry);
up(&parent->d_inode->i_sem);
......
......@@ -8,12 +8,13 @@
#include "sysfs.h"
static int sysfs_create(struct inode *dir, struct dentry *dentry, int mode)
static struct file_operations sysfs_file_operations;
static int init_file(struct inode * inode)
{
int res;
mode = (mode & S_IALLUGO) | S_IFREG;
res = sysfs_mknod(dir, dentry, mode, 0);
return res;
inode->i_size = PAGE_SIZE;
inode->i_fop = &sysfs_file_operations;
return 0;
}
#define to_subsys(k) container_of(k,struct subsystem,kset.kobj)
......@@ -325,7 +326,7 @@ static int sysfs_release(struct inode * inode, struct file * filp)
return 0;
}
struct file_operations sysfs_file_operations = {
static struct file_operations sysfs_file_operations = {
.read = sysfs_read_file,
.write = sysfs_write_file,
.llseek = generic_file_llseek,
......@@ -354,7 +355,7 @@ int sysfs_create_file(struct kobject * kobj, struct attribute * attr)
dentry = sysfs_get_dentry(parent,attr->name);
if (!IS_ERR(dentry)) {
dentry->d_fsdata = (void *)attr;
error = sysfs_create(parent->d_inode,dentry,attr->mode);
error = sysfs_create(dentry,(attr->mode & S_IALLUGO) | S_IFREG,init_file);
} else
error = PTR_ERR(dentry);
up(&parent->d_inode->i_sem);
......
......@@ -12,7 +12,7 @@
#include <linux/namei.h>
#include <linux/backing-dev.h>
extern struct file_operations sysfs_file_operations;
extern struct super_block * sysfs_sb;
static struct address_space_operations sysfs_aops = {
.readpage = simple_readpage,
......@@ -20,17 +20,14 @@ static struct address_space_operations sysfs_aops = {
.commit_write = simple_commit_write
};
static struct backing_dev_info sysfs_backing_dev_info = {
.ra_pages = 0, /* No readahead */
.memory_backed = 1, /* Does not contribute to dirty memory */
};
struct inode *sysfs_get_inode(struct super_block *sb, int mode, int dev)
struct inode * sysfs_new_inode(mode_t mode)
{
struct inode *inode = new_inode(sb);
struct inode * inode = new_inode(sysfs_sb);
if (inode) {
inode->i_mode = mode;
inode->i_uid = current->fsuid;
......@@ -41,46 +38,44 @@ struct inode *sysfs_get_inode(struct super_block *sb, int mode, int dev)
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_mapping->a_ops = &sysfs_aops;
inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
switch (mode & S_IFMT) {
default:
init_special_inode(inode, mode, dev);
break;
case S_IFREG:
inode->i_size = PAGE_SIZE;
inode->i_fop = &sysfs_file_operations;
break;
case S_IFDIR:
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inode->i_nlink++;
break;
case S_IFLNK:
inode->i_op = &page_symlink_inode_operations;
break;
}
}
return inode;
}
int sysfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
int sysfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *))
{
struct inode *inode;
int error = 0;
struct inode * inode = NULL;
if (dentry) {
if (!dentry->d_inode) {
inode = sysfs_get_inode(dir->i_sb, mode, dev);
if (inode) {
if ((inode = sysfs_new_inode(mode)))
goto Proceed;
else
error = -ENOMEM;
} else
error = -EEXIST;
} else
error = -ENOENT;
goto Done;
Proceed:
if (init)
error = init(inode);
if (!error) {
d_instantiate(dentry, inode);
dget(dentry);
} else
error = -ENOSPC;
} else
error = -EEXIST;
iput(inode);
Done:
return error;
}
int sysfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
return sysfs_create(dentry, mode, NULL);
}
struct dentry * sysfs_get_dentry(struct dentry * parent, const char * name)
{
struct qstr qstr;
......
......@@ -2,6 +2,8 @@
* mount.c - operations for initializing and mounting sysfs.
*/
#define DEBUG
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/pagemap.h>
......@@ -12,6 +14,7 @@
#define SYSFS_MAGIC 0x62656572
struct vfsmount *sysfs_mount;
struct super_block * sysfs_sb = NULL;
static struct super_operations sysfs_ops = {
.statfs = simple_statfs,
......@@ -27,10 +30,16 @@ static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
sb->s_magic = SYSFS_MAGIC;
sb->s_op = &sysfs_ops;
inode = sysfs_get_inode(sb, S_IFDIR | 0755, 0);
sysfs_sb = sb;
if (!inode) {
pr_debug("%s: could not get inode!\n",__FUNCTION__);
inode = sysfs_new_inode(S_IFDIR | S_IRUGO | S_IWUSR);
if (inode) {
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inode->i_nlink++;
} else {
pr_debug("sysfs: could not get root inode\n");
return -ENOMEM;
}
......
......@@ -9,23 +9,22 @@
#include "sysfs.h"
static int sysfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
static int init_symlink(struct inode * inode)
{
struct inode *inode;
int error = -ENOSPC;
inode->i_op = &page_symlink_inode_operations;
return 0;
}
if (dentry->d_inode)
return -EEXIST;
static int sysfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
{
int error;
inode = sysfs_get_inode(dir->i_sb, S_IFLNK|S_IRWXUGO, 0);
if (inode) {
int l = strlen(symname)+1;
error = page_symlink(inode, symname, l);
error = sysfs_create(dentry, S_IFLNK|S_IRWXUGO, init_symlink);
if (!error) {
d_instantiate(dentry, inode);
dget(dentry);
} else
iput(inode);
int l = strlen(symname)+1;
error = page_symlink(dentry->d_inode, symname, l);
if (error)
iput(dentry->d_inode);
}
return error;
}
......
extern struct vfsmount * sysfs_mount;
extern struct inode *sysfs_get_inode(struct super_block *sb, int mode, int dev);
extern int sysfs_mknod(struct inode *, struct dentry *, int, dev_t);
extern struct inode * sysfs_new_inode(mode_t mode);
extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
extern struct dentry * sysfs_get_dentry(struct dentry *, char *);
......
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