From 58f2a4c7932d8bec866d0394f806004146cde827 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Thu, 21 Jul 2011 20:01:12 -0400 Subject: [PATCH] sysfs: remove s_sibling hacks sysfs: remove s_sibling hacks s_sibling was used for three different purposes: 1) as a linked list of entries in the directory 2) as a linked list of entries to be deleted 3) as a pointer to "struct completion" This patch removes the hack and introduces new union u which holds pointers for cases 2) and 3). This change is needed for the following patch that removes s_sibling at all and replaces it with a rb tree. Signed-off-by: Mikulas Patocka Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 19 +++++++------------ fs/sysfs/sysfs.h | 5 +++++ 2 files changed, 12 insertions(+), 12 deletions(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 3e937da224d4..a4846979d4e8 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -154,7 +154,6 @@ struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) */ void sysfs_put_active(struct sysfs_dirent *sd) { - struct completion *cmpl; int v; if (unlikely(!sd)) @@ -166,10 +165,9 @@ void sysfs_put_active(struct sysfs_dirent *sd) return; /* atomic_dec_return() is a mb(), we'll always see the updated - * sd->s_sibling. + * sd->u.completion. */ - cmpl = (void *)sd->s_sibling; - complete(cmpl); + complete(sd->u.completion); } /** @@ -183,16 +181,16 @@ static void sysfs_deactivate(struct sysfs_dirent *sd) DECLARE_COMPLETION_ONSTACK(wait); int v; - BUG_ON(sd->s_sibling || !(sd->s_flags & SYSFS_FLAG_REMOVED)); + BUG_ON(!(sd->s_flags & SYSFS_FLAG_REMOVED)); if (!(sysfs_type(sd) & SYSFS_ACTIVE_REF)) return; - sd->s_sibling = (void *)&wait; + sd->u.completion = (void *)&wait; rwsem_acquire(&sd->dep_map, 0, 0, _RET_IP_); /* atomic_add_return() is a mb(), put_active() will always see - * the updated sd->s_sibling. + * the updated sd->u.completion. */ v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); @@ -201,8 +199,6 @@ static void sysfs_deactivate(struct sysfs_dirent *sd) wait_for_completion(&wait); } - sd->s_sibling = NULL; - lock_acquired(&sd->dep_map, _RET_IP_); rwsem_release(&sd->dep_map, 1, _RET_IP_); } @@ -518,7 +514,7 @@ void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) } sd->s_flags |= SYSFS_FLAG_REMOVED; - sd->s_sibling = acxt->removed; + sd->u.removed_list = acxt->removed; acxt->removed = sd; } @@ -542,8 +538,7 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) while (acxt->removed) { struct sysfs_dirent *sd = acxt->removed; - acxt->removed = sd->s_sibling; - sd->s_sibling = NULL; + acxt->removed = sd->u.removed_list; sysfs_deactivate(sd); unmap_bin_file(sd); diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index fe1a9e8650bf..3c261681713b 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -66,6 +66,11 @@ struct sysfs_dirent { struct rb_node name_node; + union { + struct completion *completion; + struct sysfs_dirent *removed_list; + } u; + const void *s_ns; /* namespace tag */ union { struct sysfs_elem_dir s_dir; -- 2.30.2