diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-07 10:03:42 +0900 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-07 11:42:15 +0900 |
commit | 0324e74534241f3f00910ec04ef67de1fe1542f4 (patch) | |
tree | 88f0b2a40a47dc0a22c0ce5e9b75a58470a56204 /fs/sysfs/symlink.c | |
parent | 1071ec7bc2dabd0a9d12a1ae5570f4fd3ba944ca (diff) | |
parent | 0cae60f91494e34a0c5391f1455f825d5849b05f (diff) |
Merge tag 'driver-core-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core / sysfs patches from Greg KH:
"Here's the big driver core / sysfs update for 3.13-rc1.
There's lots of dev_groups updates for different subsystems, as they
all get slowly migrated over to the safe versions of the attribute
groups (removing userspace races with the creation of the sysfs
files.) Also in here are some kobject updates, devres expansions, and
the first round of Tejun's sysfs reworking to enable it to be used by
other subsystems as a backend for an in-kernel filesystem.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (83 commits)
sysfs: rename sysfs_assoc_lock and explain what it's about
sysfs: use generic_file_llseek() for sysfs_file_operations
sysfs: return correct error code on unimplemented mmap()
mdio_bus: convert bus code to use dev_groups
device: Make dev_WARN/dev_WARN_ONCE print device as well as driver name
sysfs: separate out dup filename warning into a separate function
sysfs: move sysfs_hash_and_remove() to fs/sysfs/dir.c
sysfs: remove unused sysfs_get_dentry() prototype
sysfs: honor bin_attr.attr.ignore_lockdep
sysfs: merge sysfs_elem_bin_attr into sysfs_elem_attr
devres: restore zeroing behavior of devres_alloc()
sysfs: fix sysfs_write_file for bin file
input: gameport: convert bus code to use dev_groups
input: serio: remove bus usage of dev_attrs
input: serio: use DEVICE_ATTR_RO()
i2o: convert bus code to use dev_groups
memstick: convert bus code to use dev_groups
tifm: convert bus code to use dev_groups
virtio: convert bus code to use dev_groups
ipack: convert bus code to use dev_groups
...
Diffstat (limited to 'fs/sysfs/symlink.c')
-rw-r--r-- | fs/sysfs/symlink.c | 71 |
1 files changed, 31 insertions, 40 deletions
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index 2dd4507d9edd..1a23681b8179 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -28,18 +28,19 @@ static int sysfs_do_create_link_sd(struct sysfs_dirent *parent_sd, struct sysfs_dirent *target_sd = NULL; struct sysfs_dirent *sd = NULL; struct sysfs_addrm_cxt acxt; - enum kobj_ns_type ns_type; int error; BUG_ON(!name || !parent_sd); - /* target->sd can go away beneath us but is protected with - * sysfs_assoc_lock. Fetch target_sd from it. + /* + * We don't own @target and it may be removed at any time. + * Synchronize using sysfs_symlink_target_lock. See + * sysfs_remove_dir() for details. */ - spin_lock(&sysfs_assoc_lock); + spin_lock(&sysfs_symlink_target_lock); if (target->sd) target_sd = sysfs_get(target->sd); - spin_unlock(&sysfs_assoc_lock); + spin_unlock(&sysfs_symlink_target_lock); error = -ENOENT; if (!target_sd) @@ -50,29 +51,15 @@ static int sysfs_do_create_link_sd(struct sysfs_dirent *parent_sd, if (!sd) goto out_put; - ns_type = sysfs_ns_type(parent_sd); - if (ns_type) - sd->s_ns = target->ktype->namespace(target); + sd->s_ns = target_sd->s_ns; sd->s_symlink.target_sd = target_sd; target_sd = NULL; /* reference is now owned by the symlink */ - sysfs_addrm_start(&acxt, parent_sd); - /* Symlinks must be between directories with the same ns_type */ - if (!ns_type || - (ns_type == sysfs_ns_type(sd->s_symlink.target_sd->s_parent))) { - if (warn) - error = sysfs_add_one(&acxt, sd); - else - error = __sysfs_add_one(&acxt, sd); - } else { - error = -EINVAL; - WARN(1, KERN_WARNING - "sysfs: symlink across ns_types %s/%s -> %s/%s\n", - parent_sd->s_name, - sd->s_name, - sd->s_symlink.target_sd->s_parent->s_name, - sd->s_symlink.target_sd->s_name); - } + sysfs_addrm_start(&acxt); + if (warn) + error = sysfs_add_one(&acxt, sd, parent_sd); + else + error = __sysfs_add_one(&acxt, sd, parent_sd); sysfs_addrm_finish(&acxt); if (error) @@ -155,11 +142,17 @@ void sysfs_delete_link(struct kobject *kobj, struct kobject *targ, const char *name) { const void *ns = NULL; - spin_lock(&sysfs_assoc_lock); - if (targ->sd && sysfs_ns_type(kobj->sd)) + + /* + * We don't own @target and it may be removed at any time. + * Synchronize using sysfs_symlink_target_lock. See + * sysfs_remove_dir() for details. + */ + spin_lock(&sysfs_symlink_target_lock); + if (targ->sd) ns = targ->sd->s_ns; - spin_unlock(&sysfs_assoc_lock); - sysfs_hash_and_remove(kobj->sd, ns, name); + spin_unlock(&sysfs_symlink_target_lock); + sysfs_hash_and_remove(kobj->sd, name, ns); } /** @@ -176,24 +169,25 @@ void sysfs_remove_link(struct kobject *kobj, const char *name) else parent_sd = kobj->sd; - sysfs_hash_and_remove(parent_sd, NULL, name); + sysfs_hash_and_remove(parent_sd, name, NULL); } EXPORT_SYMBOL_GPL(sysfs_remove_link); /** - * sysfs_rename_link - rename symlink in object's directory. + * sysfs_rename_link_ns - rename symlink in object's directory. * @kobj: object we're acting for. * @targ: object we're pointing to. * @old: previous name of the symlink. * @new: new name of the symlink. + * @new_ns: new namespace of the symlink. * * A helper function for the common rename symlink idiom. */ -int sysfs_rename_link(struct kobject *kobj, struct kobject *targ, - const char *old, const char *new) +int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *targ, + const char *old, const char *new, const void *new_ns) { struct sysfs_dirent *parent_sd, *sd = NULL; - const void *old_ns = NULL, *new_ns = NULL; + const void *old_ns = NULL; int result; if (!kobj) @@ -205,7 +199,7 @@ int sysfs_rename_link(struct kobject *kobj, struct kobject *targ, old_ns = targ->sd->s_ns; result = -ENOENT; - sd = sysfs_get_dirent(parent_sd, old_ns, old); + sd = sysfs_get_dirent_ns(parent_sd, old, old_ns); if (!sd) goto out; @@ -215,16 +209,13 @@ int sysfs_rename_link(struct kobject *kobj, struct kobject *targ, if (sd->s_symlink.target_sd->s_dir.kobj != targ) goto out; - if (sysfs_ns_type(parent_sd)) - new_ns = targ->ktype->namespace(targ); - - result = sysfs_rename(sd, parent_sd, new_ns, new); + result = sysfs_rename(sd, parent_sd, new, new_ns); out: sysfs_put(sd); return result; } -EXPORT_SYMBOL_GPL(sysfs_rename_link); +EXPORT_SYMBOL_GPL(sysfs_rename_link_ns); static int sysfs_get_target_path(struct sysfs_dirent *parent_sd, struct sysfs_dirent *target_sd, char *path) |