sysfs, kernfs: move mount core code to fs/kernfs/mount.c (fa736a95) · Commits · e / devices / android_kernel_oneplus_sm8150

fs/kernfs/kernfs-internal.h

+22 −0

Original line number	Diff line number	Diff line
		@@ -133,6 +133,28 @@ struct sysfs_addrm_cxt {

		#include "../sysfs/sysfs.h"

		/*
		* mount.c
		*/
		struct sysfs_super_info {
		/*
		* The root associated with this super_block. Each super_block is
		* identified by the root and ns it's associated with.
		*/
		struct kernfs_root *root;

		/*
		* Each sb is associated with one namespace tag, currently the network
		* namespace of the task which mounted this sysfs instance. If multiple
		* tags become necessary, make the following an array and compare
		* sysfs_dirent tag against every entry.
		*/
		const void *ns;
		};
		#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))

		extern struct kmem_cache *sysfs_dir_cachep;

		/*
		* inode.c
		*/

fs/kernfs/mount.c

+156 −0

Original line number	Diff line number	Diff line
		@@ -7,3 +7,159 @@
		*
		* This file is released under the GPLv2.
		*/

		#include <linux/fs.h>
		#include <linux/mount.h>
		#include <linux/init.h>
		#include <linux/magic.h>
		#include <linux/slab.h>
		#include <linux/pagemap.h>

		#include "kernfs-internal.h"

		struct kmem_cache *sysfs_dir_cachep;

		static const struct super_operations sysfs_ops = {
		.statfs = simple_statfs,
		.drop_inode = generic_delete_inode,
		.evict_inode = sysfs_evict_inode,
		};

		static int sysfs_fill_super(struct super_block *sb)
		{
		struct sysfs_super_info *info = sysfs_info(sb);
		struct inode *inode;
		struct dentry *root;

		sb->s_blocksize = PAGE_CACHE_SIZE;
		sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
		sb->s_magic = SYSFS_MAGIC;
		sb->s_op = &sysfs_ops;
		sb->s_time_gran = 1;

		/* get root inode, initialize and unlock it */
		mutex_lock(&sysfs_mutex);
		inode = sysfs_get_inode(sb, info->root->sd);
		mutex_unlock(&sysfs_mutex);
		if (!inode) {
		pr_debug("sysfs: could not get root inode\n");
		return -ENOMEM;
		}

		/* instantiate and link root dentry */
		root = d_make_root(inode);
		if (!root) {
		pr_debug("%s: could not get root dentry!\n", __func__);
		return -ENOMEM;
		}
		kernfs_get(info->root->sd);
		root->d_fsdata = info->root->sd;
		sb->s_root = root;
		sb->s_d_op = &sysfs_dentry_ops;
		return 0;
		}

		static int sysfs_test_super(struct super_block sb, void data)
		{
		struct sysfs_super_info *sb_info = sysfs_info(sb);
		struct sysfs_super_info *info = data;

		return sb_info->root == info->root && sb_info->ns == info->ns;
		}

		static int sysfs_set_super(struct super_block sb, void data)
		{
		int error;
		error = set_anon_super(sb, data);
		if (!error)
		sb->s_fs_info = data;
		return error;
		}

		/**
		* kernfs_super_ns - determine the namespace tag of a kernfs super_block
		* @sb: super_block of interest
		*
		* Return the namespace tag associated with kernfs super_block @sb.
		*/
		const void kernfs_super_ns(struct super_block sb)
		{
		struct sysfs_super_info *info = sysfs_info(sb);

		return info->ns;
		}

		/**
		* kernfs_mount_ns - kernfs mount helper
		* @fs_type: file_system_type of the fs being mounted
		* @flags: mount flags specified for the mount
		* @root: kernfs_root of the hierarchy being mounted
		* @ns: optional namespace tag of the mount
		*
		* This is to be called from each kernfs user's file_system_type->mount()
		* implementation, which should pass through the specified @fs_type and
		* @flags, and specify the hierarchy and namespace tag to mount via @root
		* and @ns, respectively.
		*
		* The return value can be passed to the vfs layer verbatim.
		*/
		struct dentry kernfs_mount_ns(struct file_system_type fs_type, int flags,
		struct kernfs_root root, const void ns)
		{
		struct super_block *sb;
		struct sysfs_super_info *info;
		int error;

		info = kzalloc(sizeof(*info), GFP_KERNEL);
		if (!info)
		return ERR_PTR(-ENOMEM);

		info->root = root;
		info->ns = ns;

		sb = sget(fs_type, sysfs_test_super, sysfs_set_super, flags, info);
		if (IS_ERR(sb) \|\| sb->s_fs_info != info)
		kfree(info);
		if (IS_ERR(sb))
		return ERR_CAST(sb);
		if (!sb->s_root) {
		error = sysfs_fill_super(sb);
		if (error) {
		deactivate_locked_super(sb);
		return ERR_PTR(error);
		}
		sb->s_flags \|= MS_ACTIVE;
		}

		return dget(sb->s_root);
		}

		/**
		* kernfs_kill_sb - kill_sb for kernfs
		* @sb: super_block being killed
		*
		* This can be used directly for file_system_type->kill_sb(). If a kernfs
		* user needs extra cleanup, it can implement its own kill_sb() and call
		* this function at the end.
		*/
		void kernfs_kill_sb(struct super_block *sb)
		{
		struct sysfs_super_info *info = sysfs_info(sb);
		struct sysfs_dirent *root_sd = sb->s_root->d_fsdata;

		/*
		* Remove the superblock from fs_supers/s_instances
		* so we can't find it, before freeing sysfs_super_info.
		*/
		kill_anon_super(sb);
		kfree(info);
		kernfs_put(root_sd);
		}

		void __init kernfs_init(void)
		{
		sysfs_dir_cachep = kmem_cache_create("sysfs_dir_cache",
		sizeof(struct sysfs_dirent),
		0, SLAB_PANIC, NULL);
		sysfs_inode_init();
		}

fs/sysfs/mount.c

+0 −152

Original line number	Diff line number	Diff line
		@@ -14,91 +14,14 @@

		#include <linux/fs.h>
		#include <linux/mount.h>
		#include <linux/pagemap.h>
		#include <linux/init.h>
		#include <linux/module.h>
		#include <linux/magic.h>
		#include <linux/slab.h>
		#include <linux/user_namespace.h>

		#include "sysfs.h"


		struct kmem_cache *sysfs_dir_cachep;

		static const struct super_operations sysfs_ops = {
		.statfs = simple_statfs,
		.drop_inode = generic_delete_inode,
		.evict_inode = sysfs_evict_inode,
		};

		static struct kernfs_root *sysfs_root;
		struct sysfs_dirent *sysfs_root_sd;

		static int sysfs_fill_super(struct super_block *sb)
		{
		struct sysfs_super_info *info = sysfs_info(sb);
		struct inode *inode;
		struct dentry *root;

		sb->s_blocksize = PAGE_CACHE_SIZE;
		sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
		sb->s_magic = SYSFS_MAGIC;
		sb->s_op = &sysfs_ops;
		sb->s_time_gran = 1;

		/* get root inode, initialize and unlock it */
		mutex_lock(&sysfs_mutex);
		inode = sysfs_get_inode(sb, info->root->sd);
		mutex_unlock(&sysfs_mutex);
		if (!inode) {
		pr_debug("sysfs: could not get root inode\n");
		return -ENOMEM;
		}

		/* instantiate and link root dentry */
		root = d_make_root(inode);
		if (!root) {
		pr_debug("%s: could not get root dentry!\n", __func__);
		return -ENOMEM;
		}
		kernfs_get(info->root->sd);
		root->d_fsdata = info->root->sd;
		sb->s_root = root;
		sb->s_d_op = &sysfs_dentry_ops;
		return 0;
		}

		static int sysfs_test_super(struct super_block sb, void data)
		{
		struct sysfs_super_info *sb_info = sysfs_info(sb);
		struct sysfs_super_info *info = data;

		return sb_info->root == info->root && sb_info->ns == info->ns;
		}

		static int sysfs_set_super(struct super_block sb, void data)
		{
		int error;
		error = set_anon_super(sb, data);
		if (!error)
		sb->s_fs_info = data;
		return error;
		}

		/**
		* kernfs_super_ns - determine the namespace tag of a kernfs super_block
		* @sb: super_block of interest
		*
		* Return the namespace tag associated with kernfs super_block @sb.
		*/
		const void kernfs_super_ns(struct super_block sb)
		{
		struct sysfs_super_info *info = sysfs_info(sb);

		return info->ns;
		}

		static struct dentry sysfs_mount(struct file_system_type fs_type,
		int flags, const char dev_name, void data)
		{
		@@ -120,79 +43,12 @@ static struct dentry sysfs_mount(struct file_system_type fs_type,
		return root;
		}

		/**
		* kernfs_mount_ns - kernfs mount helper
		* @fs_type: file_system_type of the fs being mounted
		* @flags: mount flags specified for the mount
		* @root: kernfs_root of the hierarchy being mounted
		* @ns: optional namespace tag of the mount
		*
		* This is to be called from each kernfs user's file_system_type->mount()
		* implementation, which should pass through the specified @fs_type and
		* @flags, and specify the hierarchy and namespace tag to mount via @root
		* and @ns, respectively.
		*
		* The return value can be passed to the vfs layer verbatim.
		*/
		struct dentry kernfs_mount_ns(struct file_system_type fs_type, int flags,
		struct kernfs_root root, const void ns)
		{
		struct super_block *sb;
		struct sysfs_super_info *info;
		int error;

		info = kzalloc(sizeof(*info), GFP_KERNEL);
		if (!info)
		return ERR_PTR(-ENOMEM);

		info->root = root;
		info->ns = ns;

		sb = sget(fs_type, sysfs_test_super, sysfs_set_super, flags, info);
		if (IS_ERR(sb) \|\| sb->s_fs_info != info)
		kfree(info);
		if (IS_ERR(sb))
		return ERR_CAST(sb);
		if (!sb->s_root) {
		error = sysfs_fill_super(sb);
		if (error) {
		deactivate_locked_super(sb);
		return ERR_PTR(error);
		}
		sb->s_flags \|= MS_ACTIVE;
		}

		return dget(sb->s_root);
		}

		static void sysfs_kill_sb(struct super_block *sb)
		{
		kernfs_kill_sb(sb);
		kobj_ns_drop(KOBJ_NS_TYPE_NET, (void *)kernfs_super_ns(sb));
		}

		/**
		* kernfs_kill_sb - kill_sb for kernfs
		* @sb: super_block being killed
		*
		* This can be used directly for file_system_type->kill_sb(). If a kernfs
		* user needs extra cleanup, it can implement its own kill_sb() and call
		* this function at the end.
		*/
		void kernfs_kill_sb(struct super_block *sb)
		{
		struct sysfs_super_info *info = sysfs_info(sb);
		struct sysfs_dirent *root_sd = sb->s_root->d_fsdata;

		/*
		* Remove the superblock from fs_supers/s_instances
		* so we can't find it, before freeing sysfs_super_info.
		*/
		kill_anon_super(sb);
		kfree(info);
		kernfs_put(root_sd);
		}

		static struct file_system_type sysfs_fs_type = {
		.name = "sysfs",
		.mount = sysfs_mount,
		@@ -200,14 +56,6 @@ static struct file_system_type sysfs_fs_type = {
		.fs_flags = FS_USERNS_MOUNT,
		};

		void __init kernfs_init(void)
		{
		sysfs_dir_cachep = kmem_cache_create("sysfs_dir_cache",
		sizeof(struct sysfs_dirent),
		0, SLAB_PANIC, NULL);
		sysfs_inode_init();
		}

		int __init sysfs_init(void)
		{
		int err;

fs/sysfs/sysfs.h

+0 −18

Original line number	Diff line number	Diff line
		@@ -17,25 +17,7 @@
		/*
		* mount.c
		*/

		struct sysfs_super_info {
		/*
		* The root associated with this super_block. Each super_block is
		* identified by the root and ns it's associated with.
		*/
		struct kernfs_root *root;

		/*
		* Each sb is associated with one namespace tag, currently the network
		* namespace of the task which mounted this sysfs instance. If multiple
		* tags become necessary, make the following an array and compare
		* sysfs_dirent tag against every entry.
		*/
		const void *ns;
		};
		#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
		extern struct sysfs_dirent *sysfs_root_sd;
		extern struct kmem_cache *sysfs_dir_cachep;

		/*
		* dir.c