This is a note to let you know that I've just added the patch titled Subject: sysfs: Rename Support multiple superblocks
to my gregkh-2.6 tree. Its filename is sysfs-rename-support-multiple-superblocks.patch This tree can be found at http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/ >From [EMAIL PROTECTED] Thu Jul 3 18:11:52 2008 From: Eric W. Biederman <[EMAIL PROTECTED]> Date: Thu, 03 Jul 2008 18:10:05 -0700 Subject: sysfs: Rename Support multiple superblocks To: Greg Kroah-Hartman <[EMAIL PROTECTED]>, Andrew Morton <[EMAIL PROTECTED]> Cc: Tejun Heo <[EMAIL PROTECTED]>, Daniel Lezcano <[EMAIL PROTECTED]>, [EMAIL PROTECTED], Al Viro <[EMAIL PROTECTED]>, Linux Containers <[EMAIL PROTECTED]>, Benjamin Thery <[EMAIL PROTECTED]>, <[EMAIL PROTECTED]> Message-ID: <[EMAIL PROTECTED]> From: Eric W. Biederman <[EMAIL PROTECTED]> This patch modifies the sysfs_rename_dir and sysfs_move_dir routines to support multiple sysfs dentry tries rooted in different sysfs superblocks. Signed-off-by: Eric W. Biederman <[EMAIL PROTECTED]> Signed-off-by: Benjamin Thery <[EMAIL PROTECTED]> Signed-off-by: Daniel Lezcano <[EMAIL PROTECTED]> Acked-by: Tejun Heo <[EMAIL PROTECTED]> Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]> --- fs/sysfs/dir.c | 195 ++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 137 insertions(+), 58 deletions(-) --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -834,43 +834,113 @@ static struct dentry *__sysfs_get_dentry return dentry; } +struct sysfs_rename_struct { + struct list_head list; + struct dentry *old_dentry; + struct dentry *new_dentry; + struct dentry *old_parent; + struct dentry *new_parent; +}; + +static void post_rename(struct list_head *head) +{ + struct sysfs_rename_struct *srs; + while (!list_empty(head)) { + srs = list_entry(head->next, struct sysfs_rename_struct, list); + dput(srs->old_dentry); + dput(srs->new_dentry); + dput(srs->old_parent); + dput(srs->new_parent); + list_del(&srs->list); + kfree(srs); + } +} + +static int prep_rename(struct list_head *head, + struct sysfs_dirent *sd, struct sysfs_dirent *new_parent_sd, + const char *name) +{ + struct sysfs_rename_struct *srs; + struct super_block *sb; + struct dentry *dentry; + int error; + + list_for_each_entry(sb, &sysfs_fs_type.fs_supers, s_instances) { + dentry = sysfs_get_dentry(sb, sd); + if (dentry == ERR_PTR(-EXDEV)) + continue; + if (IS_ERR(dentry)) { + error = PTR_ERR(dentry); + goto err_out; + } + + srs = kzalloc(sizeof(*srs), GFP_KERNEL); + if (!srs) { + error = -ENOMEM; + dput(dentry); + goto err_out; + } + + INIT_LIST_HEAD(&srs->list); + list_add(head, &srs->list); + srs->old_dentry = dentry; + srs->old_parent = dget(dentry->d_parent); + + dentry = sysfs_get_dentry(sb, new_parent_sd); + if (IS_ERR(dentry)) { + error = PTR_ERR(dentry); + goto err_out; + } + srs->new_parent = dentry; + + error = -ENOMEM; + dentry = d_alloc_name(srs->new_parent, name); + if (!dentry) + goto err_out; + srs->new_dentry = dentry; + } + return 0; + +err_out: + post_rename(head); + return error; +} + int sysfs_rename_dir(struct kobject * kobj, const char *new_name) { struct sysfs_dirent *sd = kobj->sd; - struct dentry *parent = NULL; - struct dentry *old_dentry = NULL, *new_dentry = NULL; + struct list_head todo; + struct sysfs_rename_struct *srs; + struct inode *parent_inode = NULL; const char *dup_name = NULL; int error; + INIT_LIST_HEAD(&todo); mutex_lock(&sysfs_rename_mutex); error = 0; if (strcmp(sd->s_name, new_name) == 0) goto out; /* nothing to rename */ - /* get the original dentry */ - old_dentry = sysfs_get_dentry(sysfs_sb, sd); - if (IS_ERR(old_dentry)) { - error = PTR_ERR(old_dentry); - old_dentry = NULL; - goto out; - } + sysfs_grab_supers(); + error = prep_rename(&todo, sd, sd->s_parent, new_name); + if (error) + goto out_release; - parent = old_dentry->d_parent; + error = -ENOMEM; + mutex_lock(&sysfs_mutex); + parent_inode = sysfs_get_inode(sd->s_parent); + mutex_unlock(&sysfs_mutex); + if (!parent_inode) + goto out_release; - /* lock parent and get dentry for new name */ - mutex_lock(&parent->d_inode->i_mutex); + mutex_lock(&parent_inode->i_mutex); mutex_lock(&sysfs_mutex); error = -EEXIST; if (sysfs_find_dirent(sd->s_parent, new_name)) goto out_unlock; - error = -ENOMEM; - new_dentry = d_alloc_name(parent, new_name); - if (!new_dentry) - goto out_unlock; - /* rename sysfs_dirent */ error = -ENOMEM; new_name = dup_name = kstrdup(new_name, GFP_KERNEL); @@ -881,17 +951,21 @@ int sysfs_rename_dir(struct kobject * ko sd->s_name = new_name; /* rename */ - d_add(new_dentry, NULL); - d_move(old_dentry, new_dentry); + list_for_each_entry(srs, &todo, list) { + d_add(srs->new_dentry, NULL); + d_move(srs->old_dentry, srs->new_dentry); + } error = 0; - out_unlock: +out_unlock: mutex_unlock(&sysfs_mutex); - mutex_unlock(&parent->d_inode->i_mutex); + mutex_unlock(&parent_inode->i_mutex); kfree(dup_name); - dput(old_dentry); - dput(new_dentry); - out: +out_release: + iput(parent_inode); + post_rename(&todo); + sysfs_release_supers(); +out: mutex_unlock(&sysfs_rename_mutex); return error; } @@ -900,10 +974,12 @@ int sysfs_move_dir(struct kobject *kobj, { struct sysfs_dirent *sd = kobj->sd; struct sysfs_dirent *new_parent_sd; - struct dentry *old_parent, *new_parent = NULL; - struct dentry *old_dentry = NULL, *new_dentry = NULL; + struct list_head todo; + struct sysfs_rename_struct *srs; + struct inode *old_parent_inode = NULL, *new_parent_inode = NULL; int error; + INIT_LIST_HEAD(&todo); mutex_lock(&sysfs_rename_mutex); BUG_ON(!sd->s_parent); new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root; @@ -912,26 +988,29 @@ int sysfs_move_dir(struct kobject *kobj, if (sd->s_parent == new_parent_sd) goto out; /* nothing to move */ - /* get dentries */ - old_dentry = sysfs_get_dentry(sysfs_sb, sd); - if (IS_ERR(old_dentry)) { - error = PTR_ERR(old_dentry); - old_dentry = NULL; - goto out; - } - old_parent = old_dentry->d_parent; - - new_parent = sysfs_get_dentry(sysfs_sb, new_parent_sd); - if (IS_ERR(new_parent)) { - error = PTR_ERR(new_parent); - new_parent = NULL; - goto out; - } + sysfs_grab_supers(); + error = prep_rename(&todo, sd, new_parent_sd, sd->s_name); + if (error) + goto out_release; + + error = -ENOMEM; + mutex_lock(&sysfs_mutex); + old_parent_inode = sysfs_get_inode(sd->s_parent); + mutex_unlock(&sysfs_mutex); + if (!old_parent_inode) + goto out_release; + + error = -ENOMEM; + mutex_lock(&sysfs_mutex); + new_parent_inode = sysfs_get_inode(new_parent_sd); + mutex_unlock(&sysfs_mutex); + if (!new_parent_inode) + goto out_release; again: - mutex_lock(&old_parent->d_inode->i_mutex); - if (!mutex_trylock(&new_parent->d_inode->i_mutex)) { - mutex_unlock(&old_parent->d_inode->i_mutex); + mutex_lock(&old_parent_inode->i_mutex); + if (!mutex_trylock(&new_parent_inode->i_mutex)) { + mutex_unlock(&old_parent_inode->i_mutex); goto again; } mutex_lock(&sysfs_mutex); @@ -940,14 +1019,11 @@ again: if (sysfs_find_dirent(new_parent_sd, sd->s_name)) goto out_unlock; - error = -ENOMEM; - new_dentry = d_alloc_name(new_parent, sd->s_name); - if (!new_dentry) - goto out_unlock; - error = 0; - d_add(new_dentry, NULL); - d_move(old_dentry, new_dentry); + list_for_each_entry(srs, &todo, list) { + d_add(srs->new_dentry, NULL); + d_move(srs->old_dentry, srs->new_dentry); + } /* Remove from old parent's list and insert into new parent's list. */ sysfs_unlink_sibling(sd); @@ -956,14 +1032,17 @@ again: sd->s_parent = new_parent_sd; sysfs_link_sibling(sd); - out_unlock: +out_unlock: mutex_unlock(&sysfs_mutex); - mutex_unlock(&new_parent->d_inode->i_mutex); - mutex_unlock(&old_parent->d_inode->i_mutex); - out: - dput(new_parent); - dput(old_dentry); - dput(new_dentry); + mutex_unlock(&new_parent_inode->i_mutex); + mutex_unlock(&old_parent_inode->i_mutex); + +out_release: + iput(new_parent_inode); + iput(old_parent_inode); + post_rename(&todo); + sysfs_release_supers(); +out: mutex_unlock(&sysfs_rename_mutex); return error; } Patches currently in gregkh-2.6 which might be from [EMAIL PROTECTED] are driver-core/kobject-fix-kobject_rename-and-config_sysfs.patch driver-core/kobject-cleanup-kobject_rename-and-config_sysfs.patch driver-core/sysfs-implement-__sysfs_get_dentry.patch driver-core/sysfs-introduce-sysfs_sd_setattr-and-fix-sysfs_chmod.patch driver-core/sysfs-sysfs_get_dentry-add-a-sb-parameter.patch driver-core/sysfs-rename-support-multiple-superblocks.patch driver-core/sysfs-support-for-preventing-unmounts.patch driver-core/sysfs-sysfs_chmod_file-handle-multiple-superblocks.patch _______________________________________________ Containers mailing list [EMAIL PROTECTED] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list Devel@openvz.org https://openvz.org/mailman/listinfo/devel