From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263062AbTL2JhR (ORCPT ); Mon, 29 Dec 2003 04:37:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263178AbTL2JhR (ORCPT ); Mon, 29 Dec 2003 04:37:17 -0500 Received: from e32.co.us.ibm.com ([32.97.110.130]:29345 "EHLO e32.co.us.ibm.com") by vger.kernel.org with ESMTP id S263062AbTL2JgA (ORCPT ); Mon, 29 Dec 2003 04:36:00 -0500 Date: Mon, 29 Dec 2003 15:05:19 +0530 From: Maneesh Soni To: LKML Cc: Greg KH , Al Viro , Patrick Mochel , Dipankar Sarma Subject: [RFC 3/5] sysfs backing store (leaves only) - sysfs-leaves-file.patch Message-ID: <20031229093519.GD1649@in.ibm.com> Reply-To: maneesh@in.ibm.com References: <20031229093213.GA1649@in.ibm.com> <20031229093354.GB1649@in.ibm.com> <20031229093434.GC1649@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20031229093434.GC1649@in.ibm.com> User-Agent: Mutt/1.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org o sysfs_create_file() will just link a new sysfs_dirent() structure representing the attribute file to the kobject's s_children list. o in sysfs_create() we take extra ref. only for dentries corresponding to non-regular files or in other words pin only non-leaf dentries. fs/sysfs/file.c | 63 +++++++++++++++++++++++++------------------------------ fs/sysfs/inode.c | 19 +++++++++++++--- 2 files changed, 45 insertions(+), 37 deletions(-) diff -puN fs/sysfs/file.c~sysfs-leaves-file fs/sysfs/file.c --- linux-2.6.0/fs/sysfs/file.c~sysfs-leaves-file 2003-12-29 12:43:44.000000000 +0530 +++ linux-2.6.0-maneesh/fs/sysfs/file.c 2003-12-29 12:43:44.000000000 +0530 @@ -9,14 +9,6 @@ #include "sysfs.h" -static struct file_operations sysfs_file_operations; - -static int init_file(struct inode * inode) -{ - inode->i_size = PAGE_SIZE; - inode->i_fop = &sysfs_file_operations; - return 0; -} #define to_subsys(k) container_of(k,struct subsystem,kset.kobj) #define to_sattr(a) container_of(a,struct subsys_attribute,attr) @@ -77,8 +69,10 @@ struct sysfs_buffer { */ static int fill_read_buffer(struct file * file, struct sysfs_buffer * buffer) { - struct attribute * attr = file->f_dentry->d_fsdata; - struct kobject * kobj = file->f_dentry->d_parent->d_fsdata; + struct sysfs_dirent * sd_attr = file->f_dentry->d_fsdata; + struct attribute * attr = sd_attr->s_element; + struct sysfs_dirent * sd_kobj = file->f_dentry->d_parent->d_fsdata; + struct kobject * kobj = sd_kobj->s_element; struct sysfs_ops * ops = buffer->ops; int ret = 0; ssize_t count; @@ -198,8 +192,10 @@ fill_write_buffer(struct sysfs_buffer * static int flush_write_buffer(struct file * file, struct sysfs_buffer * buffer, size_t count) { - struct attribute * attr = file->f_dentry->d_fsdata; - struct kobject * kobj = file->f_dentry->d_parent->d_fsdata; + struct sysfs_dirent * sd_attr = file->f_dentry->d_fsdata; + struct attribute * attr = sd_attr->s_element; + struct sysfs_dirent * sd_kobj = file->f_dentry->d_parent->d_fsdata; + struct kobject * kobj = sd_kobj->s_element; struct sysfs_ops * ops = buffer->ops; return ops->store(kobj,attr,buffer->page,count); @@ -238,8 +234,10 @@ sysfs_write_file(struct file *file, cons static int check_perm(struct inode * inode, struct file * file) { - struct kobject * kobj = kobject_get(file->f_dentry->d_parent->d_fsdata); - struct attribute * attr = file->f_dentry->d_fsdata; + struct sysfs_dirent * sd_attr = file->f_dentry->d_fsdata; + struct attribute * attr = sd_attr->s_element; + struct sysfs_dirent * sd_kobj = file->f_dentry->d_parent->d_fsdata; + struct kobject * kobj = kobject_get(sd_kobj->s_element); struct sysfs_buffer * buffer; struct sysfs_ops * ops = NULL; int error = 0; @@ -320,8 +318,10 @@ static int sysfs_open_file(struct inode static int sysfs_release(struct inode * inode, struct file * filp) { - struct kobject * kobj = filp->f_dentry->d_parent->d_fsdata; - struct attribute * attr = filp->f_dentry->d_fsdata; + struct sysfs_dirent * sd_attr = filp->f_dentry->d_fsdata; + struct attribute * attr = sd_attr->s_element; + struct sysfs_dirent * sd_kobj = filp->f_dentry->d_parent->d_fsdata; + struct kobject * kobj = kobject_get(sd_kobj->s_element); struct sysfs_buffer * buffer = filp->private_data; if (kobj) @@ -336,7 +336,7 @@ static int sysfs_release(struct inode * return 0; } -static struct file_operations sysfs_file_operations = { +struct file_operations sysfs_file_operations = { .read = sysfs_read_file, .write = sysfs_write_file, .llseek = generic_file_llseek, @@ -345,23 +345,18 @@ static struct file_operations sysfs_file }; -int sysfs_add_file(struct dentry * dir, const struct attribute * attr) +int sysfs_add_file(struct dentry * parent, int t, const struct attribute * attr) { - struct dentry * dentry; - int error; + struct sysfs_dirent * sd; + struct sysfs_dirent * parent_sd = parent->d_fsdata; + int error = 0; - down(&dir->d_inode->i_sem); - dentry = sysfs_get_dentry(dir,attr->name); - if (!IS_ERR(dentry)) { - error = sysfs_create(dentry, - (attr->mode & S_IALLUGO) | S_IFREG, - init_file); - if (!error) - dentry->d_fsdata = (void *)attr; - dput(dentry); - } else - error = PTR_ERR(dentry); - up(&dir->d_inode->i_sem); + down(&parent->d_inode->i_sem); + sd = sysfs_new_dirent(parent_sd, (void *) attr, t); + if (!sd) + error = -ENOMEM; + up(&parent->d_inode->i_sem); + return error; } @@ -374,8 +369,8 @@ int sysfs_add_file(struct dentry * dir, int sysfs_create_file(struct kobject * kobj, const struct attribute * attr) { - if (kobj && attr) - return sysfs_add_file(kobj->dentry,attr); + if (kobj && kobj->dentry && attr) + return sysfs_add_file(kobj->dentry, SYSFS_KOBJ_ATTR, attr); return -EINVAL; } diff -puN fs/sysfs/inode.c~sysfs-leaves-file fs/sysfs/inode.c --- linux-2.6.0/fs/sysfs/inode.c~sysfs-leaves-file 2003-12-29 12:43:44.000000000 +0530 +++ linux-2.6.0-maneesh/fs/sysfs/inode.c 2003-12-29 12:43:44.000000000 +0530 @@ -11,6 +11,8 @@ #include #include #include +#include "sysfs.h" + extern struct super_block * sysfs_sb; static struct address_space_operations sysfs_aops = { @@ -61,7 +63,8 @@ int sysfs_create(struct dentry * dentry, error = init(inode); if (!error) { d_instantiate(dentry, inode); - dget(dentry); /* Extra count - pin the dentry in core */ + if (!S_ISREG(inode->i_mode)) + dget(dentry); /* pin non-leaf dentry in core */ } else iput(inode); Done: @@ -96,14 +99,24 @@ void sysfs_hash_and_remove(struct dentry pr_debug("sysfs: Removing %s (%d)\n", victim->d_name.name, atomic_read(&victim->d_count)); - d_delete(victim); - simple_unlink(dir->d_inode,victim); + if (S_ISREG(victim->d_inode->i_mode)) { + spin_lock(&dcache_lock); + spin_lock(&victim->d_lock); + __d_drop(victim); + spin_unlock(&dcache_lock); + spin_unlock(&victim->d_lock); + } + else { + d_delete(victim); + simple_unlink(dir->d_inode,victim); + } } /* * Drop reference from sysfs_get_dentry() above. */ dput(victim); } + sysfs_remove_attr_dirent(dir->d_fsdata, name); up(&dir->d_inode->i_sem); } _ -- Maneesh Soni Linux Technology Center, IBM Software Lab, Bangalore, India email: maneesh@in.ibm.com Phone: 91-80-5044999 Fax: 91-80-5268553 T/L : 9243696