From d69ac5a0bbcf1d9962883fb23e337caf5b38cec8 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 18 Sep 2013 17:15:35 -0400 Subject: sysfs: remove sysfs_addrm_cxt->parent_sd sysfs_addrm_start/finish() enclose sysfs_dirent additions and deletions and sysfs_addrm_cxt is used to record information necessary to finish the operations. Currently, sysfs_addrm_start() takes @parent_sd, records it in sysfs_addrm_cxt, and assumes that all operations in the block are performed under that @parent_sd. This assumption has been fine until now but we want to make some operations behave recursively and, while having @parent_sd recorded in sysfs_addrm_cxt doesn't necessarily prevents that, it becomes confusing. This patch removes sysfs_addrm_cxt->parent_sd and makes sysfs_add_one() take an explicit @parent_sd parameter. Note that sysfs_remove_one() doesn't need the extra argument as its parent is always known from the target @sd. While at it, add __acquires/releases() notations to sysfs_addrm_start/finish() respectively. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 52 +++++++++++++++++++++++++++------------------------- 1 file changed, 27 insertions(+), 25 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index d23e66dfba74..671868914b5b 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -406,22 +406,19 @@ struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type) /** * sysfs_addrm_start - prepare for sysfs_dirent add/remove * @acxt: pointer to sysfs_addrm_cxt to be used - * @parent_sd: parent sysfs_dirent * - * This function is called when the caller is about to add or - * remove sysfs_dirent under @parent_sd. This function acquires - * sysfs_mutex. @acxt is used to keep and pass context to - * other addrm functions. + * This function is called when the caller is about to add or remove + * sysfs_dirent. This function acquires sysfs_mutex. @acxt is used + * to keep and pass context to other addrm functions. * * LOCKING: * Kernel thread context (may sleep). sysfs_mutex is locked on * return. */ -void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, - struct sysfs_dirent *parent_sd) +void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt) + __acquires(sysfs_mutex) { memset(acxt, 0, sizeof(*acxt)); - acxt->parent_sd = parent_sd; mutex_lock(&sysfs_mutex); } @@ -430,10 +427,11 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, * __sysfs_add_one - add sysfs_dirent to parent without warning * @acxt: addrm context to use * @sd: sysfs_dirent to be added + * @parent_sd: the parent sysfs_dirent to add @sd to * - * Get @acxt->parent_sd and set sd->s_parent to it and increment - * nlink of parent inode if @sd is a directory and link into the - * children list of the parent. + * Get @parent_sd and set @sd->s_parent to it and increment nlink of + * the parent inode if @sd is a directory and link into the children + * list of the parent. * * This function should be called between calls to * sysfs_addrm_start() and sysfs_addrm_finish() and should be @@ -446,20 +444,21 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, * 0 on success, -EEXIST if entry with the given name already * exists. */ -int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) +int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, + struct sysfs_dirent *parent_sd) { struct sysfs_inode_attrs *ps_iattr; int ret; sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); - sd->s_parent = sysfs_get(acxt->parent_sd); + sd->s_parent = sysfs_get(parent_sd); ret = sysfs_link_sibling(sd); if (ret) return ret; /* Update timestamps on the parent */ - ps_iattr = acxt->parent_sd->s_iattr; + ps_iattr = parent_sd->s_iattr; if (ps_iattr) { struct iattr *ps_iattrs = &ps_iattr->ia_iattr; ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; @@ -493,10 +492,11 @@ static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) * sysfs_add_one - add sysfs_dirent to parent * @acxt: addrm context to use * @sd: sysfs_dirent to be added + * @parent_sd: the parent sysfs_dirent to add @sd to * - * Get @acxt->parent_sd and set sd->s_parent to it and increment - * nlink of parent inode if @sd is a directory and link into the - * children list of the parent. + * Get @parent_sd and set @sd->s_parent to it and increment nlink of + * the parent inode if @sd is a directory and link into the children + * list of the parent. * * This function should be called between calls to * sysfs_addrm_start() and sysfs_addrm_finish() and should be @@ -509,17 +509,18 @@ static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) * 0 on success, -EEXIST if entry with the given name already * exists. */ -int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) +int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, + struct sysfs_dirent *parent_sd) { int ret; - ret = __sysfs_add_one(acxt, sd); + ret = __sysfs_add_one(acxt, sd, parent_sd); if (ret == -EEXIST) { char *path = kzalloc(PATH_MAX, GFP_KERNEL); WARN(1, KERN_WARNING "sysfs: cannot create duplicate filename '%s'\n", (path == NULL) ? sd->s_name - : (sysfs_pathname(acxt->parent_sd, path), + : (sysfs_pathname(parent_sd, path), strlcat(path, "/", PATH_MAX), strlcat(path, sd->s_name, PATH_MAX), path)); @@ -553,7 +554,7 @@ void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) sysfs_unlink_sibling(sd); /* Update timestamps on the parent */ - ps_iattr = acxt->parent_sd->s_iattr; + ps_iattr = sd->s_parent->s_iattr; if (ps_iattr) { struct iattr *ps_iattrs = &ps_iattr->ia_iattr; ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; @@ -576,6 +577,7 @@ void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) * sysfs_mutex is released. */ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) + __releases(sysfs_mutex) { /* release resources acquired by sysfs_addrm_start() */ mutex_unlock(&sysfs_mutex); @@ -678,8 +680,8 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, sd->s_dir.kobj = kobj; /* link in */ - sysfs_addrm_start(&acxt, parent_sd); - rc = sysfs_add_one(&acxt, sd); + sysfs_addrm_start(&acxt); + rc = sysfs_add_one(&acxt, sd, parent_sd); sysfs_addrm_finish(&acxt); if (rc == 0) @@ -772,7 +774,7 @@ static void remove_dir(struct sysfs_dirent *sd) { struct sysfs_addrm_cxt acxt; - sysfs_addrm_start(&acxt, sd->s_parent); + sysfs_addrm_start(&acxt); sysfs_remove_one(&acxt, sd); sysfs_addrm_finish(&acxt); } @@ -792,7 +794,7 @@ static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) return; pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); - sysfs_addrm_start(&acxt, dir_sd); + sysfs_addrm_start(&acxt); pos = rb_first(&dir_sd->s_dir.children); while (pos) { struct sysfs_dirent *sd = to_sysfs_dirent(pos); -- cgit v1.2.3