From: Christoph Hellwig Subject: [PATCH 04/42] proc: simplify proc_register calling conventions Date: Wed, 16 May 2018 11:43:08 +0200 Message-ID: <20180516094346.20506-5-hch@lst.de> References: <20180516094346.20506-1-hch@lst.de> Cc: Alexey Dobriyan , Greg Kroah-Hartman , Jiri Slaby , Alessandro Zummo , Alexandre Belloni , linux-acpi@vger.kernel.org, drbd-dev@lists.linbit.com, linux-ide@vger.kernel.org, netdev@vger.kernel.org, linux-rtc@vger.kernel.org, megaraidlinux.pdl@broadcom.com, linux-scsi@vger.kernel.org, devel@driverdev.osuosl.org, linux-afs@lists.infradead.org, linux-ext4@vger.kernel.org, jfs-discussion@lists.sourceforge.net, netfilter-devel@vger.kernel.org, linux-kernel@vger.kernel.org To: Andrew Morton , Alexander Viro Return-path: In-Reply-To: <20180516094346.20506-1-hch@lst.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Return registered entry on success, return NULL on failure and free the passed in entry. Also expose it in internal.h as we'll start using it in proc_net.c soon. Signed-off-by: Christoph Hellwig --- fs/proc/generic.c | 44 ++++++++++++++++++-------------------------- fs/proc/internal.h | 2 ++ 2 files changed, 20 insertions(+), 26 deletions(-) diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 2078e70e1595..bd8480ff0d35 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -346,13 +346,12 @@ static const struct inode_operations proc_dir_inode_operations = { .setattr = proc_notify_change, }; -static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp) +/* returns the registered entry, or frees dp and returns NULL on failure */ +struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, + struct proc_dir_entry *dp) { - int ret; - - ret = proc_alloc_inum(&dp->low_ino); - if (ret) - return ret; + if (proc_alloc_inum(&dp->low_ino)) + goto out_free_entry; write_lock(&proc_subdir_lock); dp->parent = dir; @@ -360,12 +359,16 @@ static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp WARN(1, "proc_dir_entry '%s/%s' already registered\n", dir->name, dp->name); write_unlock(&proc_subdir_lock); - proc_free_inum(dp->low_ino); - return -EEXIST; + goto out_free_inum; } write_unlock(&proc_subdir_lock); - return 0; + return dp; +out_free_inum: + proc_free_inum(dp->low_ino); +out_free_entry: + pde_free(dp); + return NULL; } static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, @@ -443,10 +446,7 @@ struct proc_dir_entry *proc_symlink(const char *name, if (ent->data) { strcpy((char*)ent->data,dest); ent->proc_iops = &proc_link_inode_operations; - if (proc_register(parent, ent) < 0) { - pde_free(ent); - ent = NULL; - } + ent = proc_register(parent, ent); } else { pde_free(ent); ent = NULL; @@ -470,11 +470,9 @@ struct proc_dir_entry *proc_mkdir_data(const char *name, umode_t mode, ent->proc_fops = &proc_dir_operations; ent->proc_iops = &proc_dir_inode_operations; parent->nlink++; - if (proc_register(parent, ent) < 0) { - pde_free(ent); + ent = proc_register(parent, ent); + if (!ent) parent->nlink--; - ent = NULL; - } } return ent; } @@ -505,11 +503,9 @@ struct proc_dir_entry *proc_create_mount_point(const char *name) ent->proc_fops = NULL; ent->proc_iops = NULL; parent->nlink++; - if (proc_register(parent, ent) < 0) { - pde_free(ent); + ent = proc_register(parent, ent); + if (!ent) parent->nlink--; - ent = NULL; - } } return ent; } @@ -539,11 +535,7 @@ struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, pde->proc_fops = proc_fops; pde->data = data; pde->proc_iops = &proc_file_inode_operations; - if (proc_register(parent, pde) < 0) - goto out_free; - return pde; -out_free: - pde_free(pde); + return proc_register(parent, pde); out: return NULL; } diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 0f1692e63cb6..488e67490312 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -162,6 +162,8 @@ extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, i /* * generic.c */ +struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, + struct proc_dir_entry *dp); extern struct dentry *proc_lookup(struct inode *, struct dentry *, unsigned int); struct dentry *proc_lookup_de(struct inode *, struct dentry *, struct proc_dir_entry *); extern int proc_readdir(struct file *, struct dir_context *); -- 2.17.0