From 035ed7a49447bc8e15d4d9316fc6a359b2d94333 Mon Sep 17 00:00:00 2001 From: Thomas Maier Date: Sun, 22 Oct 2006 19:17:47 +0200 Subject: sysfs: sysfs_write_file() writes zero terminated data since most of the files in sysfs are text files, it would be nice, if the "store" function called during sysfs_write_file() gets a zero terminated string / data. The current implementation seems not to ensure this. (But only if it is the first time the zeroed buffer page is allocated.) So the buffer can be scanned by sscanf() easily, for example. This patch simply sets a \0 char behind the data in buffer->page. Signed-off-by: Thomas Maier Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/file.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs') diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 298303b5a716..95c165101c98 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -190,6 +190,9 @@ fill_write_buffer(struct sysfs_buffer * buffer, const char __user * buf, size_t count = PAGE_SIZE - 1; error = copy_from_user(buffer->page,buf,count); buffer->needs_read_fill = 1; + /* if buf is assumed to contain a string, terminate it by \0, + so e.g. sscanf() can scan the string easily */ + buffer->page[count] = 0; return error ? -EFAULT : count; } -- cgit v1.2.3-59-g8ed1b From 8a82472f86bf693b8e91ed56c9ca4f62fbbdcfa3 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Mon, 20 Nov 2006 17:07:51 +0100 Subject: driver core: Introduce device_move(): move a device to a new parent. Provide a function device_move() to move a device to a new parent device. Add auxilliary functions kobject_move() and sysfs_move_dir(). kobject_move() generates a new uevent of type KOBJ_MOVE, containing the previous path (DEVPATH_OLD) in addition to the usual values. For this, a new interface kobject_uevent_env() is created that allows to add further environmental data to the uevent at the kobject layer. Signed-off-by: Cornelia Huck Acked-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++++ fs/sysfs/dir.c | 45 ++++++++++++++++++++++++ include/linux/device.h | 1 + include/linux/kobject.h | 8 +++++ include/linux/sysfs.h | 8 +++++ lib/kobject.c | 50 +++++++++++++++++++++++++++ lib/kobject_uevent.c | 28 ++++++++++++--- 7 files changed, 228 insertions(+), 4 deletions(-) (limited to 'fs') diff --git a/drivers/base/core.c b/drivers/base/core.c index 75b45a10935a..e4eaf46c4d93 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -955,3 +955,95 @@ int device_rename(struct device *dev, char *new_name) return error; } + + +static int device_move_class_links(struct device *dev, + struct device *old_parent, + struct device *new_parent) +{ +#ifdef CONFIG_SYSFS_DEPRECATED + int error; + char *class_name; + + class_name = make_class_name(dev->class->name, &dev->kobj); + if (!class_name) { + error = PTR_ERR(class_name); + class_name = NULL; + goto out; + } + if (old_parent) { + sysfs_remove_link(&dev->kobj, "device"); + sysfs_remove_link(&old_parent->kobj, class_name); + } + error = sysfs_create_link(&dev->kobj, &new_parent->kobj, "device"); + if (error) + goto out; + error = sysfs_create_link(&new_parent->kobj, &dev->kobj, class_name); + if (error) + sysfs_remove_link(&dev->kobj, "device"); +out: + kfree(class_name); + return error; +#else + return 0; +#endif +} + +/** + * device_move - moves a device to a new parent + * @dev: the pointer to the struct device to be moved + * @new_parent: the new parent of the device + */ +int device_move(struct device *dev, struct device *new_parent) +{ + int error; + struct device *old_parent; + + dev = get_device(dev); + if (!dev) + return -EINVAL; + + if (!device_is_registered(dev)) { + error = -EINVAL; + goto out; + } + new_parent = get_device(new_parent); + if (!new_parent) { + error = -EINVAL; + goto out; + } + pr_debug("DEVICE: moving '%s' to '%s'\n", dev->bus_id, + new_parent->bus_id); + error = kobject_move(&dev->kobj, &new_parent->kobj); + if (error) { + put_device(new_parent); + goto out; + } + old_parent = dev->parent; + dev->parent = new_parent; + if (old_parent) + klist_del(&dev->knode_parent); + klist_add_tail(&dev->knode_parent, &new_parent->klist_children); + if (!dev->class) + goto out_put; + error = device_move_class_links(dev, old_parent, new_parent); + if (error) { + /* We ignore errors on cleanup since we're hosed anyway... */ + device_move_class_links(dev, new_parent, old_parent); + if (!kobject_move(&dev->kobj, &old_parent->kobj)) { + klist_del(&dev->knode_parent); + if (old_parent) + klist_add_tail(&dev->knode_parent, + &old_parent->klist_children); + } + put_device(new_parent); + goto out; + } +out_put: + put_device(old_parent); +out: + put_device(dev); + return error; +} + +EXPORT_SYMBOL_GPL(device_move); diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 3aa3434621ca..a5782e8c7f07 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -372,6 +372,51 @@ int sysfs_rename_dir(struct kobject * kobj, const char *new_name) return error; } +int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent) +{ + struct dentry *old_parent_dentry, *new_parent_dentry, *new_dentry; + struct sysfs_dirent *new_parent_sd, *sd; + int error; + + if (!new_parent) + return -EINVAL; + + old_parent_dentry = kobj->parent ? + kobj->parent->dentry : sysfs_mount->mnt_sb->s_root; + new_parent_dentry = new_parent->dentry; + +again: + mutex_lock(&old_parent_dentry->d_inode->i_mutex); + if (!mutex_trylock(&new_parent_dentry->d_inode->i_mutex)) { + mutex_unlock(&old_parent_dentry->d_inode->i_mutex); + goto again; + } + + new_parent_sd = new_parent_dentry->d_fsdata; + sd = kobj->dentry->d_fsdata; + + new_dentry = lookup_one_len(kobj->name, new_parent_dentry, + strlen(kobj->name)); + if (IS_ERR(new_dentry)) { + error = PTR_ERR(new_dentry); + goto out; + } else + error = 0; + d_add(new_dentry, NULL); + d_move(kobj->dentry, new_dentry); + dput(new_dentry); + + /* Remove from old parent's list and insert into new parent's list. */ + list_del_init(&sd->s_sibling); + list_add(&sd->s_sibling, &new_parent_sd->s_children); + +out: + mutex_unlock(&new_parent_dentry->d_inode->i_mutex); + mutex_unlock(&old_parent_dentry->d_inode->i_mutex); + + return error; +} + static int sysfs_dir_open(struct inode *inode, struct file *file) { struct dentry * dentry = file->f_dentry; diff --git a/include/linux/device.h b/include/linux/device.h index 0a0370c74181..583a341e016c 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -424,6 +424,7 @@ extern int device_for_each_child(struct device *, void *, extern struct device *device_find_child(struct device *, void *data, int (*match)(struct device *, void *)); extern int device_rename(struct device *dev, char *new_name); +extern int device_move(struct device *dev, struct device *new_parent); /* * Manual binding of a device to driver. See drivers/base/bus.c diff --git a/include/linux/kobject.h b/include/linux/kobject.h index bcd9cd173c2c..d1c8d28fa92e 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -47,6 +47,7 @@ enum kobject_action { KOBJ_UMOUNT = (__force kobject_action_t) 0x05, /* umount event for block devices (broken) */ KOBJ_OFFLINE = (__force kobject_action_t) 0x06, /* device offline */ KOBJ_ONLINE = (__force kobject_action_t) 0x07, /* device online */ + KOBJ_MOVE = (__force kobject_action_t) 0x08, /* device move */ }; struct kobject { @@ -76,6 +77,7 @@ extern int __must_check kobject_add(struct kobject *); extern void kobject_del(struct kobject *); extern int __must_check kobject_rename(struct kobject *, const char *new_name); +extern int __must_check kobject_move(struct kobject *, struct kobject *); extern int __must_check kobject_register(struct kobject *); extern void kobject_unregister(struct kobject *); @@ -264,6 +266,8 @@ extern int __must_check subsys_create_file(struct subsystem * , #if defined(CONFIG_HOTPLUG) void kobject_uevent(struct kobject *kobj, enum kobject_action action); +void kobject_uevent_env(struct kobject *kobj, enum kobject_action action, + char *envp[]); int add_uevent_var(char **envp, int num_envp, int *cur_index, char *buffer, int buffer_size, int *cur_len, @@ -271,6 +275,10 @@ int add_uevent_var(char **envp, int num_envp, int *cur_index, __attribute__((format (printf, 7, 8))); #else static inline void kobject_uevent(struct kobject *kobj, enum kobject_action action) { } +static inline void kobject_uevent_env(struct kobject *kobj, + enum kobject_action action, + char *envp[]) +{ } static inline int add_uevent_var(char **envp, int num_envp, int *cur_index, char *buffer, int buffer_size, int *cur_len, diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 6d5c43d31dec..2129d1b6c874 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -96,6 +96,9 @@ sysfs_remove_dir(struct kobject *); extern int __must_check sysfs_rename_dir(struct kobject *, const char *new_name); +extern int __must_check +sysfs_move_dir(struct kobject *, struct kobject *); + extern int __must_check sysfs_create_file(struct kobject *, const struct attribute *); @@ -142,6 +145,11 @@ static inline int sysfs_rename_dir(struct kobject * k, const char *new_name) return 0; } +static inline int sysfs_move_dir(struct kobject * k, struct kobject * new_parent) +{ + return 0; +} + static inline int sysfs_create_file(struct kobject * k, const struct attribute * a) { return 0; diff --git a/lib/kobject.c b/lib/kobject.c index 7dd5c0e9d996..744a4b102c7f 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -310,6 +310,56 @@ int kobject_rename(struct kobject * kobj, const char *new_name) return error; } +/** + * kobject_move - move object to another parent + * @kobj: object in question. + * @new_parent: object's new parent + */ + +int kobject_move(struct kobject *kobj, struct kobject *new_parent) +{ + int error; + struct kobject *old_parent; + const char *devpath = NULL; + char *devpath_string = NULL; + char *envp[2]; + + kobj = kobject_get(kobj); + if (!kobj) + return -EINVAL; + new_parent = kobject_get(new_parent); + if (!new_parent) { + error = -EINVAL; + goto out; + } + /* old object path */ + devpath = kobject_get_path(kobj, GFP_KERNEL); + if (!devpath) { + error = -ENOMEM; + goto out; + } + devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL); + if (!devpath_string) { + error = -ENOMEM; + goto out; + } + sprintf(devpath_string, "DEVPATH_OLD=%s", devpath); + envp[0] = devpath_string; + envp[1] = NULL; + error = sysfs_move_dir(kobj, new_parent); + if (error) + goto out; + old_parent = kobj->parent; + kobj->parent = new_parent; + kobject_put(old_parent); + kobject_uevent_env(kobj, KOBJ_MOVE, envp); +out: + kobject_put(kobj); + kfree(devpath_string); + kfree(devpath); + return error; +} + /** * kobject_del - unlink kobject from hierarchy. * @kobj: object. diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 7f20e7b857cb..a1922765ff31 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -50,18 +50,22 @@ static char *action_to_string(enum kobject_action action) return "offline"; case KOBJ_ONLINE: return "online"; + case KOBJ_MOVE: + return "move"; default: return NULL; } } /** - * kobject_uevent - notify userspace by ending an uevent + * kobject_uevent_env - send an uevent with environmental data * - * @action: action that is happening (usually KOBJ_ADD and KOBJ_REMOVE) + * @action: action that is happening (usually KOBJ_MOVE) * @kobj: struct kobject that the action is happening to + * @envp_ext: pointer to environmental data */ -void kobject_uevent(struct kobject *kobj, enum kobject_action action) +void kobject_uevent_env(struct kobject *kobj, enum kobject_action action, + char *envp_ext[]) { char **envp; char *buffer; @@ -76,6 +80,7 @@ void kobject_uevent(struct kobject *kobj, enum kobject_action action) char *seq_buff; int i = 0; int retval; + int j; pr_debug("%s\n", __FUNCTION__); @@ -134,7 +139,8 @@ void kobject_uevent(struct kobject *kobj, enum kobject_action action) scratch += sprintf (scratch, "DEVPATH=%s", devpath) + 1; envp [i++] = scratch; scratch += sprintf(scratch, "SUBSYSTEM=%s", subsystem) + 1; - + for (j = 0; envp_ext && envp_ext[j]; j++) + envp[i++] = envp_ext[j]; /* just reserve the space, overwrite it after kset call has returned */ envp[i++] = seq_buff = scratch; scratch += strlen("SEQNUM=18446744073709551616") + 1; @@ -200,6 +206,20 @@ exit: kfree(envp); return; } + +EXPORT_SYMBOL_GPL(kobject_uevent_env); + +/** + * kobject_uevent - notify userspace by ending an uevent + * + * @action: action that is happening (usually KOBJ_ADD and KOBJ_REMOVE) + * @kobj: struct kobject that the action is happening to + */ +void kobject_uevent(struct kobject *kobj, enum kobject_action action) +{ + kobject_uevent_env(kobj, action, NULL); +} + EXPORT_SYMBOL_GPL(kobject_uevent); /** -- cgit v1.2.3-59-g8ed1b