From d635711daa98be86d4c7fd01499c34f566b54ccb Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Fri, 10 Jun 2016 05:30:17 -0300 Subject: Linux-libre 4.6.2-gnu --- fs/devpts/inode.c | 100 +++++++++++++++++++----------------------------------- 1 file changed, 35 insertions(+), 65 deletions(-) (limited to 'fs/devpts') diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c index 655f21f99..0b2954d71 100644 --- a/fs/devpts/inode.c +++ b/fs/devpts/inode.c @@ -128,6 +128,7 @@ static const match_table_t tokens = { struct pts_fs_info { struct ida allocated_ptys; struct pts_mount_opts mount_opts; + struct super_block *sb; struct dentry *ptmx_dentry; }; @@ -358,7 +359,7 @@ static const struct super_operations devpts_sops = { .show_options = devpts_show_options, }; -static void *new_pts_fs_info(void) +static void *new_pts_fs_info(struct super_block *sb) { struct pts_fs_info *fsi; @@ -369,6 +370,7 @@ static void *new_pts_fs_info(void) ida_init(&fsi->allocated_ptys); fsi->mount_opts.mode = DEVPTS_DEFAULT_MODE; fsi->mount_opts.ptmxmode = DEVPTS_DEFAULT_PTMX_MODE; + fsi->sb = sb; return fsi; } @@ -384,7 +386,7 @@ devpts_fill_super(struct super_block *s, void *data, int silent) s->s_op = &devpts_sops; s->s_time_gran = 1; - s->s_fs_info = new_pts_fs_info(); + s->s_fs_info = new_pts_fs_info(s); if (!s->s_fs_info) goto fail; @@ -524,17 +526,14 @@ static struct file_system_type devpts_fs_type = { * to the System V naming convention */ -int devpts_new_index(struct inode *ptmx_inode) +int devpts_new_index(struct pts_fs_info *fsi) { - struct super_block *sb = pts_sb_from_inode(ptmx_inode); - struct pts_fs_info *fsi; int index; int ida_ret; - if (!sb) + if (!fsi) return -ENODEV; - fsi = DEVPTS_SB(sb); retry: if (!ida_pre_get(&fsi->allocated_ptys, GFP_KERNEL)) return -ENOMEM; @@ -564,11 +563,8 @@ retry: return index; } -void devpts_kill_index(struct inode *ptmx_inode, int idx) +void devpts_kill_index(struct pts_fs_info *fsi, int idx) { - struct super_block *sb = pts_sb_from_inode(ptmx_inode); - struct pts_fs_info *fsi = DEVPTS_SB(sb); - mutex_lock(&allocated_ptys_lock); ida_remove(&fsi->allocated_ptys, idx); pty_count--; @@ -578,21 +574,25 @@ void devpts_kill_index(struct inode *ptmx_inode, int idx) /* * pty code needs to hold extra references in case of last /dev/tty close */ - -void devpts_add_ref(struct inode *ptmx_inode) +struct pts_fs_info *devpts_get_ref(struct inode *ptmx_inode, struct file *file) { - struct super_block *sb = pts_sb_from_inode(ptmx_inode); + struct super_block *sb; + struct pts_fs_info *fsi; + + sb = pts_sb_from_inode(ptmx_inode); + if (!sb) + return NULL; + fsi = DEVPTS_SB(sb); + if (!fsi) + return NULL; atomic_inc(&sb->s_active); - ihold(ptmx_inode); + return fsi; } -void devpts_del_ref(struct inode *ptmx_inode) +void devpts_put_ref(struct pts_fs_info *fsi) { - struct super_block *sb = pts_sb_from_inode(ptmx_inode); - - iput(ptmx_inode); - deactivate_super(sb); + deactivate_super(fsi->sb); } /** @@ -604,22 +604,20 @@ void devpts_del_ref(struct inode *ptmx_inode) * * The created inode is returned. Remove it from /dev/pts/ by devpts_pty_kill. */ -struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index, - void *priv) +struct dentry *devpts_pty_new(struct pts_fs_info *fsi, int index, void *priv) { struct dentry *dentry; - struct super_block *sb = pts_sb_from_inode(ptmx_inode); + struct super_block *sb; struct inode *inode; struct dentry *root; - struct pts_fs_info *fsi; struct pts_mount_opts *opts; char s[12]; - if (!sb) + if (!fsi) return ERR_PTR(-ENODEV); + sb = fsi->sb; root = sb->s_root; - fsi = DEVPTS_SB(sb); opts = &fsi->mount_opts; inode = new_inode(sb); @@ -630,25 +628,21 @@ struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index, inode->i_uid = opts->setuid ? opts->uid : current_fsuid(); inode->i_gid = opts->setgid ? opts->gid : current_fsgid(); inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; - init_special_inode(inode, S_IFCHR|opts->mode, device); - inode->i_private = priv; + init_special_inode(inode, S_IFCHR|opts->mode, MKDEV(UNIX98_PTY_SLAVE_MAJOR, index)); sprintf(s, "%d", index); - inode_lock(d_inode(root)); - dentry = d_alloc_name(root, s); if (dentry) { + dentry->d_fsdata = priv; d_add(dentry, inode); fsnotify_create(d_inode(root), dentry); } else { iput(inode); - inode = ERR_PTR(-ENOMEM); + dentry = ERR_PTR(-ENOMEM); } - inode_unlock(d_inode(root)); - - return inode; + return dentry; } /** @@ -657,24 +651,10 @@ struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index, * * Returns whatever was passed as priv in devpts_pty_new for a given inode. */ -void *devpts_get_priv(struct inode *pts_inode) +void *devpts_get_priv(struct dentry *dentry) { - struct dentry *dentry; - void *priv = NULL; - - BUG_ON(pts_inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR)); - - /* Ensure dentry has not been deleted by devpts_pty_kill() */ - dentry = d_find_alias(pts_inode); - if (!dentry) - return NULL; - - if (pts_inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC) - priv = pts_inode->i_private; - - dput(dentry); - - return priv; + WARN_ON_ONCE(dentry->d_sb->s_magic != DEVPTS_SUPER_MAGIC); + return dentry->d_fsdata; } /** @@ -683,24 +663,14 @@ void *devpts_get_priv(struct inode *pts_inode) * * This is an inverse operation of devpts_pty_new. */ -void devpts_pty_kill(struct inode *inode) +void devpts_pty_kill(struct dentry *dentry) { - struct super_block *sb = pts_sb_from_inode(inode); - struct dentry *root = sb->s_root; - struct dentry *dentry; + WARN_ON_ONCE(dentry->d_sb->s_magic != DEVPTS_SUPER_MAGIC); - BUG_ON(inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR)); - - inode_lock(d_inode(root)); - - dentry = d_find_alias(inode); - - drop_nlink(inode); + dentry->d_fsdata = NULL; + drop_nlink(dentry->d_inode); d_delete(dentry); dput(dentry); /* d_alloc_name() in devpts_pty_new() */ - dput(dentry); /* d_find_alias above */ - - inode_unlock(d_inode(root)); } static int __init init_devpts_fs(void) -- cgit v1.2.3-54-g00ecf