diff options
Diffstat (limited to 'fs/gfs2/glock.h')
| -rw-r--r-- | fs/gfs2/glock.h | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h index 9ad4a6ac6c84..5e12220cc0c2 100644 --- a/fs/gfs2/glock.h +++ b/fs/gfs2/glock.h @@ -13,6 +13,7 @@ #include <linux/sched.h> #include <linux/parser.h> #include "incore.h" +#include "util.h" /* Options for hostdata parser */ @@ -181,7 +182,9 @@ static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl) extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, const struct gfs2_glock_operations *glops, int create, struct gfs2_glock **glp); +extern void gfs2_glock_hold(struct gfs2_glock *gl); extern void gfs2_glock_put(struct gfs2_glock *gl); +extern void gfs2_glock_queue_put(struct gfs2_glock *gl); extern void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, u16 flags, struct gfs2_holder *gh); extern void gfs2_holder_reinit(unsigned int state, u16 flags, @@ -257,11 +260,44 @@ static inline bool gfs2_holder_initialized(struct gfs2_holder *gh) return gh->gh_gl; } +/** + * glock_set_object - set the gl_object field of a glock + * @gl: the glock + * @object: the object + */ static inline void glock_set_object(struct gfs2_glock *gl, void *object) { spin_lock(&gl->gl_lockref.lock); + if (gfs2_assert_warn(gl->gl_name.ln_sbd, gl->gl_object == NULL)) + gfs2_dump_glock(NULL, gl); gl->gl_object = object; spin_unlock(&gl->gl_lockref.lock); } +/** + * glock_clear_object - clear the gl_object field of a glock + * @gl: the glock + * @object: the object + * + * I'd love to similarly add this: + * else if (gfs2_assert_warn(gl->gl_sbd, gl->gl_object == object)) + * gfs2_dump_glock(NULL, gl); + * Unfortunately, that's not possible because as soon as gfs2_delete_inode + * frees the block in the rgrp, another process can reassign it for an I_NEW + * inode in gfs2_create_inode because that calls new_inode, not gfs2_iget. + * That means gfs2_delete_inode may subsequently try to call this function + * for a glock that's already pointing to a brand new inode. If we clear the + * new inode's gl_object, we'll introduce metadata corruption. Function + * gfs2_delete_inode calls clear_inode which calls gfs2_clear_inode which also + * tries to clear gl_object, so it's more than just gfs2_delete_inode. + * + */ +static inline void glock_clear_object(struct gfs2_glock *gl, void *object) +{ + spin_lock(&gl->gl_lockref.lock); + if (gl->gl_object == object) + gl->gl_object = NULL; + spin_unlock(&gl->gl_lockref.lock); +} + #endif /* __GLOCK_DOT_H__ */ |