diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/eventpoll.c | 172 |
1 files changed, 3 insertions, 169 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c index b5c7ca5..2831c8f 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -34,6 +34,7 @@ #include <linux/mount.h> #include <linux/bitops.h> #include <linux/mutex.h> +#include <linux/anon_inodes.h> #include <asm/uaccess.h> #include <asm/system.h> #include <asm/io.h> @@ -75,8 +76,6 @@ */ -#define EVENTPOLLFS_MAGIC 0x03111965 /* My birthday should work for this :) */ - #define DEBUG_EPOLL 0 #if DEBUG_EPOLL > 0 @@ -228,8 +227,6 @@ struct ep_pqueue { static void ep_poll_safewake_init(struct poll_safewake *psw); static void ep_poll_safewake(struct poll_safewake *psw, wait_queue_head_t *wq); -static int ep_getfd(int *efd, struct inode **einode, struct file **efile, - struct eventpoll *ep); static int ep_alloc(struct eventpoll **pep); static void ep_free(struct eventpoll *ep); static struct epitem *ep_find(struct eventpoll *ep, struct file *file, int fd); @@ -255,11 +252,6 @@ static int ep_events_transfer(struct eventpoll *ep, int maxevents); static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events, int maxevents, long timeout); -static int eventpollfs_delete_dentry(struct dentry *dentry); -static struct inode *ep_eventpoll_inode(void); -static int eventpollfs_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *data, struct vfsmount *mnt); /* * This semaphore is used to serialize ep_free() and eventpoll_release_file(). @@ -275,30 +267,12 @@ static struct kmem_cache *epi_cache __read_mostly; /* Slab cache used to allocate "struct eppoll_entry" */ static struct kmem_cache *pwq_cache __read_mostly; -/* Virtual fs used to allocate inodes for eventpoll files */ -static struct vfsmount *eventpoll_mnt __read_mostly; - /* File callbacks that implement the eventpoll file behaviour */ static const struct file_operations eventpoll_fops = { .release = ep_eventpoll_close, .poll = ep_eventpoll_poll }; -/* - * This is used to register the virtual file system from where - * eventpoll inodes are allocated. - */ -static struct file_system_type eventpoll_fs_type = { - .name = "eventpollfs", - .get_sb = eventpollfs_get_sb, - .kill_sb = kill_anon_super, -}; - -/* Very basic directory entry operations for the eventpoll virtual file system */ -static struct dentry_operations eventpollfs_dentry_operations = { - .d_delete = eventpollfs_delete_dentry, -}; - /* Fast test to see if the file is an evenpoll file */ @@ -495,7 +469,8 @@ asmlinkage long sys_epoll_create(int size) * Creates all the items needed to setup an eventpoll file. That is, * a file structure, and inode and a free file descriptor. */ - error = ep_getfd(&fd, &inode, &file, ep); + error = anon_inode_getfd(&fd, &inode, &file, "[eventpoll]", + &eventpoll_fops, ep); if (error) goto eexit_2; @@ -725,82 +700,6 @@ asmlinkage long sys_epoll_pwait(int epfd, struct epoll_event __user *events, #endif /* #ifdef TIF_RESTORE_SIGMASK */ -/* - * Creates the file descriptor to be used by the epoll interface. - */ -static int ep_getfd(int *efd, struct inode **einode, struct file **efile, - struct eventpoll *ep) -{ - struct qstr this; - char name[32]; - struct dentry *dentry; - struct inode *inode; - struct file *file; - int error, fd; - - /* Get an ready to use file */ - error = -ENFILE; - file = get_empty_filp(); - if (!file) - goto eexit_1; - - /* Allocates an inode from the eventpoll file system */ - inode = ep_eventpoll_inode(); - if (IS_ERR(inode)) { - error = PTR_ERR(inode); - goto eexit_2; - } - - /* Allocates a free descriptor to plug the file onto */ - error = get_unused_fd(); - if (error < 0) - goto eexit_3; - fd = error; - - /* - * Link the inode to a directory entry by creating a unique name - * using the inode number. - */ - error = -ENOMEM; - sprintf(name, "[%lu]", inode->i_ino); - this.name = name; - this.len = strlen(name); - this.hash = inode->i_ino; - dentry = d_alloc(eventpoll_mnt->mnt_sb->s_root, &this); - if (!dentry) - goto eexit_4; - dentry->d_op = &eventpollfs_dentry_operations; - d_add(dentry, inode); - file->f_path.mnt = mntget(eventpoll_mnt); - file->f_path.dentry = dentry; - file->f_mapping = inode->i_mapping; - - file->f_pos = 0; - file->f_flags = O_RDONLY; - file->f_op = &eventpoll_fops; - file->f_mode = FMODE_READ; - file->f_version = 0; - file->private_data = ep; - - /* Install the new setup file into the allocated fd. */ - fd_install(fd, file); - - *efd = fd; - *einode = inode; - *efile = file; - return 0; - -eexit_4: - put_unused_fd(fd); -eexit_3: - iput(inode); -eexit_2: - put_filp(file); -eexit_1: - return error; -} - - static int ep_alloc(struct eventpoll **pep) { struct eventpoll *ep = kzalloc(sizeof(*ep), GFP_KERNEL); @@ -1553,52 +1452,8 @@ retry: return res; } -static int eventpollfs_delete_dentry(struct dentry *dentry) -{ - - return 1; -} - -static struct inode *ep_eventpoll_inode(void) -{ - int error = -ENOMEM; - struct inode *inode = new_inode(eventpoll_mnt->mnt_sb); - - if (!inode) - goto eexit_1; - - inode->i_fop = &eventpoll_fops; - - /* - * Mark the inode dirty from the very beginning, - * that way it will never be moved to the dirty - * list because mark_inode_dirty() will think - * that it already _is_ on the dirty list. - */ - inode->i_state = I_DIRTY; - inode->i_mode = S_IRUSR | S_IWUSR; - inode->i_uid = current->fsuid; - inode->i_gid = current->fsgid; - inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; - return inode; - -eexit_1: - return ERR_PTR(error); -} - -static int -eventpollfs_get_sb(struct file_system_type *fs_type, int flags, - const char *dev_name, void *data, struct vfsmount *mnt) -{ - return get_sb_pseudo(fs_type, "eventpoll:", NULL, EVENTPOLLFS_MAGIC, - mnt); -} - - static int __init eventpoll_init(void) { - int error; - mutex_init(&epmutex); /* Initialize the structure used to perform safe poll wait head wake ups */ @@ -1614,34 +1469,13 @@ static int __init eventpoll_init(void) sizeof(struct eppoll_entry), 0, EPI_SLAB_DEBUG|SLAB_PANIC, NULL, NULL); - /* - * Register the virtual file system that will be the source of inodes - * for the eventpoll files - */ - error = register_filesystem(&eventpoll_fs_type); - if (error) - goto epanic; - - /* Mount the above commented virtual file system */ - eventpoll_mnt = kern_mount(&eventpoll_fs_type); - error = PTR_ERR(eventpoll_mnt); - if (IS_ERR(eventpoll_mnt)) - goto epanic; - - DNPRINTK(3, (KERN_INFO "[%p] eventpoll: successfully initialized.\n", - current)); return 0; - -epanic: - panic("eventpoll_init() failed\n"); } static void __exit eventpoll_exit(void) { /* Undo all operations done inside eventpoll_init() */ - unregister_filesystem(&eventpoll_fs_type); - mntput(eventpoll_mnt); kmem_cache_destroy(pwq_cache); kmem_cache_destroy(epi_cache); } |