diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/sysfs/bin.c | 1 | ||||
| -rw-r--r-- | fs/sysfs/dir.c | 1 | ||||
| -rw-r--r-- | fs/sysfs/file.c | 67 | ||||
| -rw-r--r-- | fs/sysfs/group.c | 1 | ||||
| -rw-r--r-- | fs/sysfs/inode.c | 24 | ||||
| -rw-r--r-- | fs/sysfs/mount.c | 9 | ||||
| -rw-r--r-- | fs/sysfs/symlink.c | 1 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 16 |
8 files changed, 103 insertions, 17 deletions
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c index e8f540d..9ec1c85 100644 --- a/fs/sysfs/bin.c +++ b/fs/sysfs/bin.c @@ -16,6 +16,7 @@ #include <linux/slab.h> #include <asm/uaccess.h> +#include <asm/semaphore.h> #include "sysfs.h" diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 2bab1b4..9ff0449 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -9,6 +9,7 @@ #include <linux/module.h> #include <linux/kobject.h> #include <linux/namei.h> +#include <asm/semaphore.h> #include "sysfs.h" DECLARE_RWSEM(sysfs_rename_sem); diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 9cfe53e..cba4c1c 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -7,6 +7,7 @@ #include <linux/kobject.h> #include <linux/namei.h> #include <linux/poll.h> +#include <linux/list.h> #include <asm/uaccess.h> #include <asm/semaphore.h> @@ -50,17 +51,29 @@ static struct sysfs_ops subsys_sysfs_ops = { .store = subsys_attr_store, }; +/** + * add_to_collection - add buffer to a collection + * @buffer: buffer to be added + * @node inode of set to add to + */ -struct sysfs_buffer { - size_t count; - loff_t pos; - char * page; - struct sysfs_ops * ops; - struct semaphore sem; - int needs_read_fill; - int event; -}; +static inline void +add_to_collection(struct sysfs_buffer *buffer, struct inode *node) +{ + struct sysfs_buffer_collection *set = node->i_private; + mutex_lock(&node->i_mutex); + list_add(&buffer->associates, &set->associates); + mutex_unlock(&node->i_mutex); +} + +static inline void +remove_from_collection(struct sysfs_buffer *buffer, struct inode *node) +{ + mutex_lock(&node->i_mutex); + list_del(&buffer->associates); + mutex_unlock(&node->i_mutex); +} /** * fill_read_buffer - allocate and fill buffer from object. @@ -153,6 +166,10 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos) ssize_t retval = 0; down(&buffer->sem); + if (buffer->orphaned) { + retval = -ENODEV; + goto out; + } if (buffer->needs_read_fill) { if ((retval = fill_read_buffer(file->f_path.dentry,buffer))) goto out; @@ -165,7 +182,6 @@ out: return retval; } - /** * fill_write_buffer - copy buffer from userspace. * @buffer: data buffer for file. @@ -243,19 +259,25 @@ sysfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t ssize_t len; down(&buffer->sem); + if (buffer->orphaned) { + len = -ENODEV; + goto out; + } len = fill_write_buffer(buffer, buf, count); if (len > 0) len = flush_write_buffer(file->f_path.dentry, buffer, len); if (len > 0) *ppos += len; +out: up(&buffer->sem); return len; } -static int check_perm(struct inode * inode, struct file * file) +static int sysfs_open_file(struct inode *inode, struct file *file) { struct kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent); struct attribute * attr = to_attr(file->f_path.dentry); + struct sysfs_buffer_collection *set; struct sysfs_buffer * buffer; struct sysfs_ops * ops = NULL; int error = 0; @@ -285,6 +307,18 @@ static int check_perm(struct inode * inode, struct file * file) if (!ops) goto Eaccess; + /* make sure we have a collection to add our buffers to */ + mutex_lock(&inode->i_mutex); + if (!(set = inode->i_private)) { + if (!(set = inode->i_private = kmalloc(sizeof(struct sysfs_buffer_collection), GFP_KERNEL))) { + error = -ENOMEM; + goto Done; + } else { + INIT_LIST_HEAD(&set->associates); + } + } + mutex_unlock(&inode->i_mutex); + /* File needs write support. * The inode's perms must say it's ok, * and we must have a store method. @@ -310,9 +344,11 @@ static int check_perm(struct inode * inode, struct file * file) */ buffer = kzalloc(sizeof(struct sysfs_buffer), GFP_KERNEL); if (buffer) { + INIT_LIST_HEAD(&buffer->associates); init_MUTEX(&buffer->sem); buffer->needs_read_fill = 1; buffer->ops = ops; + add_to_collection(buffer, inode); file->private_data = buffer; } else error = -ENOMEM; @@ -330,11 +366,6 @@ static int check_perm(struct inode * inode, struct file * file) return error; } -static int sysfs_open_file(struct inode * inode, struct file * filp) -{ - return check_perm(inode,filp); -} - static int sysfs_release(struct inode * inode, struct file * filp) { struct kobject * kobj = to_kobj(filp->f_path.dentry->d_parent); @@ -342,6 +373,8 @@ static int sysfs_release(struct inode * inode, struct file * filp) struct module * owner = attr->owner; struct sysfs_buffer * buffer = filp->private_data; + if (buffer) + remove_from_collection(buffer, inode); if (kobj) kobject_put(kobj); /* After this point, attr should not be accessed. */ @@ -548,7 +581,7 @@ EXPORT_SYMBOL_GPL(sysfs_chmod_file); void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr) { - sysfs_hash_and_remove(kobj->dentry,attr->name); + sysfs_hash_and_remove(kobj->dentry, attr->name); } diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c index 122145b..46a277b 100644 --- a/fs/sysfs/group.c +++ b/fs/sysfs/group.c @@ -13,6 +13,7 @@ #include <linux/dcache.h> #include <linux/namei.h> #include <linux/err.h> +#include <asm/semaphore.h> #include "sysfs.h" diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c index e79e38d..1a81ebc 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -13,6 +13,7 @@ #include <linux/backing-dev.h> #include <linux/capability.h> #include <linux/errno.h> +#include <asm/semaphore.h> #include "sysfs.h" extern struct super_block * sysfs_sb; @@ -209,6 +210,22 @@ const unsigned char * sysfs_get_name(struct sysfs_dirent *sd) return NULL; } +static inline void orphan_all_buffers(struct inode *node) +{ + struct sysfs_buffer_collection *set = node->i_private; + struct sysfs_buffer *buf; + + mutex_lock(&node->i_mutex); + if (node->i_private) { + list_for_each_entry(buf, &set->associates, associates) { + down(&buf->sem); + buf->orphaned = 1; + up(&buf->sem); + } + } + mutex_unlock(&node->i_mutex); +} + /* * Unhashes the dentry corresponding to given sysfs_dirent @@ -217,16 +234,23 @@ const unsigned char * sysfs_get_name(struct sysfs_dirent *sd) void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent) { struct dentry * dentry = sd->s_dentry; + struct inode *inode; if (dentry) { spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (!(d_unhashed(dentry) && dentry->d_inode)) { + inode = dentry->d_inode; + spin_lock(&inode->i_lock); + __iget(inode); + spin_unlock(&inode->i_lock); dget_locked(dentry); __d_drop(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); simple_unlink(parent->d_inode, dentry); + orphan_all_buffers(inode); + iput(inode); } else { spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index e503f85..a1a58b9 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -8,6 +8,7 @@ #include <linux/mount.h> #include <linux/pagemap.h> #include <linux/init.h> +#include <asm/semaphore.h> #include "sysfs.h" @@ -18,9 +19,12 @@ struct vfsmount *sysfs_mount; struct super_block * sysfs_sb = NULL; struct kmem_cache *sysfs_dir_cachep; +static void sysfs_clear_inode(struct inode *inode); + static struct super_operations sysfs_ops = { .statfs = simple_statfs, .drop_inode = generic_delete_inode, + .clear_inode = sysfs_clear_inode, }; static struct sysfs_dirent sysfs_root = { @@ -31,6 +35,11 @@ static struct sysfs_dirent sysfs_root = { .s_iattr = NULL, }; +static void sysfs_clear_inode(struct inode *inode) +{ + kfree(inode->i_private); +} + static int sysfs_fill_super(struct super_block *sb, void *data, int silent) { struct inode *inode; diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index f50e3cc..4869f61 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -7,6 +7,7 @@ #include <linux/module.h> #include <linux/kobject.h> #include <linux/namei.h> +#include <asm/semaphore.h> #include "sysfs.h" diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index bd7cec2..39c623f 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -33,6 +33,22 @@ struct sysfs_symlink { struct kobject * target_kobj; }; +struct sysfs_buffer { + struct list_head associates; + size_t count; + loff_t pos; + char * page; + struct sysfs_ops * ops; + struct semaphore sem; + int orphaned; + int needs_read_fill; + int event; +}; + +struct sysfs_buffer_collection { + struct list_head associates; +}; + static inline struct kobject * to_kobj(struct dentry * dentry) { struct sysfs_dirent * sd = dentry->d_fsdata; |
