[JFFS2][XATTR] Remove 'struct list_head ilist' from jffs2_inode_cache.

This patch can reduce 4-byte of memory usage per inode_cache.

[4/10] jffs2-xattr-v5.1-04-remove_ilist_from_ic.patch

Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>

9 files changed, 55 insertions, 43 deletions

diff --git a/fs/jffs2/jffs2_fs_sb.h b/fs/jffs2/jffs2_fs_sb.h
index 3b4e0edd6dbb..272fbea55192 100644
--- a/fs/jffs2/jffs2_fs_sb.h
+++ b/fs/jffs2/jffs2_fs_sb.h
@@ -119,8 +119,8 @@ struct jffs2_sb_info {
 #define XATTRINDEX_HASHSIZE     (57)
         uint32_t highest_xid;
         struct list_head xattrindex[XATTRINDEX_HASHSIZE];
-        struct list_head xattr_temp;
         struct list_head xattr_unchecked;
+        struct jffs2_xattr_ref *xref_temp;
         struct rw_semaphore xattr_sem;
         uint32_t xdatum_mem_usage;
         uint32_t xdatum_mem_threshold;
diff --git a/fs/jffs2/malloc.c b/fs/jffs2/malloc.c
index 3d5b7ecfbf8d..f2473fa2fd16 100644
--- a/fs/jffs2/malloc.c
+++ b/fs/jffs2/malloc.c
@@ -259,7 +259,6 @@ struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void)
 
         memset(ref, 0, sizeof(struct jffs2_xattr_ref));
         ref->class = RAWNODE_CLASS_XATTR_REF;
-        INIT_LIST_HEAD(&ref->ilist);
         return ref;
 }
 
diff --git a/fs/jffs2/nodelist.h b/fs/jffs2/nodelist.h
index 6f6279cf4909..351d947c9375 100644
--- a/fs/jffs2/nodelist.h
+++ b/fs/jffs2/nodelist.h
@@ -117,7 +117,7 @@ struct jffs2_inode_cache {
         uint32_t ino;
         int nlink;
 #ifdef CONFIG_JFFS2_FS_XATTR
-        struct list_head ilist;
+        struct jffs2_xattr_ref *xref;
 #endif
 };
 
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index 61ccdf4f1042..e1acce8fb2bf 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -902,7 +902,6 @@ int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
                 f->inocache->ino = f->inocache->nlink = 1;
                 f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache;
                 f->inocache->state = INO_STATE_READING;
-                init_xattr_inode_cache(f->inocache);
                 jffs2_add_ino_cache(c, f->inocache);
         }
         if (!f->inocache) {
diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c
index f09689e320fe..0a79fc921e9f 100644
--- a/fs/jffs2/scan.c
+++ b/fs/jffs2/scan.c
@@ -408,14 +408,15 @@ static int jffs2_scan_xref_node(struct jffs2_sb_info *c, struct jffs2_eraseblock
          * ref->xid is used to store 32bit xid, xd is not used
          * ref->ino is used to store 32bit inode-number, ic is not used
          * Thoes variables are declared as union, thus using those
-         * are exclusive. In a similar way, ref->ilist is temporarily
+         * are exclusive. In a similar way, ref->next is temporarily
          * used to chain all xattr_ref object. It's re-chained to
          * jffs2_inode_cache in jffs2_build_xattr_subsystem() correctly.
          */
         ref->node = raw;
         ref->ino = je32_to_cpu(rr->ino);
         ref->xid = je32_to_cpu(rr->xid);
-        list_add_tail(&ref->ilist, &c->xattr_temp);
+        ref->next = c->xref_temp;
+        c->xref_temp = ref;
 
         raw->__totlen = PAD(je32_to_cpu(rr->totlen));
         raw->flash_offset = ofs | REF_PRISTINE;
@@ -888,7 +889,6 @@ struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uin
 
         ic->ino = ino;
         ic->nodes = (void *)ic;
-        init_xattr_inode_cache(ic);
         jffs2_add_ino_cache(c, ic);
         if (ino == 1)
                 ic->nlink = 1;
diff --git a/fs/jffs2/summary.c b/fs/jffs2/summary.c
index 5d9ec8e36528..831a42c13059 100644
--- a/fs/jffs2/summary.c
+++ b/fs/jffs2/summary.c
@@ -556,7 +556,8 @@ static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eras
                                 ref->ino = 0xfffffffe;
                                 ref->xid = 0xfffffffd;
                                 ref->node = raw;
-                                list_add_tail(&ref->ilist, &c->xattr_temp);
+                                ref->next = c->xref_temp;
+                                c->xref_temp = ref;
 
                                 raw->__totlen = PAD(sizeof(struct jffs2_raw_xref));
                                 raw->flash_offset = ofs | REF_UNCHECKED;
diff --git a/fs/jffs2/write.c b/fs/jffs2/write.c
index d5c78195f3b8..ff2b00b604ec 100644
--- a/fs/jffs2/write.c
+++ b/fs/jffs2/write.c
@@ -36,7 +36,6 @@ int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint
         f->inocache->nlink = 1;
         f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache;
         f->inocache->state = INO_STATE_PRESENT;
-        init_xattr_inode_cache(f->inocache);
 
         jffs2_add_ino_cache(c, f->inocache);
         D1(printk(KERN_DEBUG "jffs2_do_new_inode(): Assigned ino# %d\n", f->inocache->ino));
diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c
index c9a185c54ce7..b16bc71c9cd2 100644
--- a/fs/jffs2/xattr.c
+++ b/fs/jffs2/xattr.c
@@ -456,7 +456,7 @@ static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
  *   is called to remove xrefs related to obsolete inode when inode is unlinked.
  * jffs2_xattr_free_inode(c, ic)
  *   is called to release xattr related objects when unmounting. 
- * check_xattr_ref_ilist(c, ic)
+ * check_xattr_ref_inode(c, ic)
  *   is used to confirm inode does not have duplicate xattr name/value pair.
  * -------------------------------------------------- */
 static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
@@ -549,7 +549,6 @@ static void delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *re
         BUG_ON(!ref->node);
         delete_xattr_ref_node(c, ref);
 
-        list_del(&ref->ilist);
         xd = ref->xd;
         xd->refcnt--;
         if (!xd->refcnt)
@@ -629,7 +628,8 @@ static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct
         }
 
         /* Chain to inode */
-        list_add(&ref->ilist, &ic->ilist);
+        ref->next = ic->xref;
+        ic->xref = ref;
 
         return ref; /* success */
 }
@@ -644,8 +644,11 @@ void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache
                 return;
 
         down_write(&c->xattr_sem);
-        list_for_each_entry_safe(ref, _ref, &ic->ilist, ilist)
+        for (ref = ic->xref; ref; ref = _ref) {
+                _ref = ref->next;
                 delete_xattr_ref(c, ref);
+        }
+        ic->xref = NULL;
         up_write(&c->xattr_sem);
 }
 
@@ -656,8 +659,8 @@ void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *i
         struct jffs2_xattr_ref *ref, *_ref;
 
         down_write(&c->xattr_sem);
-        list_for_each_entry_safe(ref, _ref, &ic->ilist, ilist) {
-                list_del(&ref->ilist);
+        for (ref = ic->xref; ref; ref = _ref) {
+                _ref = ref->next;
                 xd = ref->xd;
                 xd->refcnt--;
                 if (!xd->refcnt) {
@@ -666,16 +669,17 @@ void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *i
                 }
                 jffs2_free_xattr_ref(ref);
         }
+        ic->xref = NULL;
         up_write(&c->xattr_sem);
 }
 
-static int check_xattr_ref_ilist(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
 {
-        /* success of check_xattr_ref_ilist() means taht inode (ic) dose not have
+        /* success of check_xattr_ref_inode() means taht inode (ic) dose not have
          * duplicate name/value pairs. If duplicate name/value pair would be found,
          * one will be removed.
          */
-        struct jffs2_xattr_ref *ref, *cmp;
+        struct jffs2_xattr_ref *ref, *cmp, **pref;
         int rc = 0;
 
         if (likely(ic->flags & INO_FLAGS_XATTR_CHECKED))
@@ -683,22 +687,23 @@ static int check_xattr_ref_ilist(struct jffs2_sb_info *c, struct jffs2_inode_cac
         down_write(&c->xattr_sem);
  retry:
         rc = 0;
-        list_for_each_entry(ref, &ic->ilist, ilist) {
+        for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
                 if (!ref->xd->xname) {
                         rc = load_xattr_datum(c, ref->xd);
                         if (unlikely(rc > 0)) {
+                                *pref = ref->next;
                                 delete_xattr_ref(c, ref);
                                 goto retry;
                         } else if (unlikely(rc < 0))
                                 goto out;
                 }
-                cmp = ref;
-                list_for_each_entry_continue(cmp, &ic->ilist, ilist) {
+                for (cmp=ref->next, pref=&ref->next; cmp; pref=&cmp->next, cmp=cmp->next) {
                         if (!cmp->xd->xname) {
                                 ref->xd->flags |= JFFS2_XFLAGS_BIND;
                                 rc = load_xattr_datum(c, cmp->xd);
                                 ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
                                 if (unlikely(rc > 0)) {
+                                        *pref = cmp->next;
                                         delete_xattr_ref(c, cmp);
                                         goto retry;
                                 } else if (unlikely(rc < 0))
@@ -706,6 +711,7 @@ static int check_xattr_ref_ilist(struct jffs2_sb_info *c, struct jffs2_inode_cac
                         }
                         if (ref->xd->xprefix == cmp->xd->xprefix
                             && !strcmp(ref->xd->xname, cmp->xd->xname)) {
+                                *pref = cmp->next;
                                 delete_xattr_ref(c, cmp);
                                 goto retry;
                         }
@@ -736,8 +742,8 @@ void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c)
 
         for (i=0; i < XATTRINDEX_HASHSIZE; i++)
                 INIT_LIST_HEAD(&c->xattrindex[i]);
-        INIT_LIST_HEAD(&c->xattr_temp);
         INIT_LIST_HEAD(&c->xattr_unchecked);
+        c->xref_temp = NULL;
 
         init_rwsem(&c->xattr_sem);
         c->xdatum_mem_usage = 0;
@@ -765,8 +771,11 @@ void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c)
         struct jffs2_xattr_ref *ref, *_ref;
         int i;
 
-        list_for_each_entry_safe(ref, _ref, &c->xattr_temp, ilist)
+        for (ref=c->xref_temp; ref; ref = _ref) {
+                _ref = ref->next;
                 jffs2_free_xattr_ref(ref);
+        }
+        c->xref_temp = NULL;
 
         for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
@@ -788,8 +797,8 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
         BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
 
         /* Phase.1 */
-        list_for_each_entry_safe(ref, _ref, &c->xattr_temp, ilist) {
-                list_del_init(&ref->ilist);
+        for (ref=c->xref_temp; ref; ref=_ref) {
+                _ref = ref->next;
                 /* checking REF_UNCHECKED nodes */
                 if (ref_flags(ref->node) != REF_PRISTINE) {
                         if (verify_xattr_ref(c, ref)) {
@@ -813,9 +822,11 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
                 ref->xd = xd;
                 ref->ic = ic;
                 xd->refcnt++;
-                list_add_tail(&ref->ilist, &ic->ilist);
+                ref->next = ic->xref;
+                ic->xref = ref;
                 xref_count++;
         }
+        c->xref_temp = NULL;
         /* After this, ref->xid/ino are NEVER used. */
 
         /* Phase.2 */
@@ -931,20 +942,20 @@ ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
         struct jffs2_inode_cache *ic = f->inocache;
-        struct jffs2_xattr_ref *ref;
+        struct jffs2_xattr_ref *ref, **pref;
         struct jffs2_xattr_datum *xd;
         struct xattr_handler *xhandle;
         ssize_t len, rc;
         int retry = 0;
 
-        rc = check_xattr_ref_ilist(c, ic);
+        rc = check_xattr_ref_inode(c, ic);
         if (unlikely(rc))
                 return rc;
 
         down_read(&c->xattr_sem);
  retry:
         len = 0;
-        list_for_each_entry(ref, &ic->ilist, ilist) {
+        for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
                 BUG_ON(ref->ic != ic);
                 xd = ref->xd;
                 if (!xd->xname) {
@@ -957,6 +968,7 @@ ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
                         } else {
                                 rc = load_xattr_datum(c, xd);
                                 if (unlikely(rc > 0)) {
+                                        *pref = ref->next;
                                         delete_xattr_ref(c, ref);
                                         goto retry;
                                 } else if (unlikely(rc < 0))
@@ -992,16 +1004,16 @@ int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
         struct jffs2_inode_cache *ic = f->inocache;
         struct jffs2_xattr_datum *xd;
-        struct jffs2_xattr_ref *ref;
+        struct jffs2_xattr_ref *ref, **pref;
         int rc, retry = 0;
 
-        rc = check_xattr_ref_ilist(c, ic);
+        rc = check_xattr_ref_inode(c, ic);
         if (unlikely(rc))
                 return rc;
 
         down_read(&c->xattr_sem);
  retry:
-        list_for_each_entry(ref, &ic->ilist, ilist) {
+        for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
                 BUG_ON(ref->ic!=ic);
 
                 xd = ref->xd;
@@ -1017,6 +1029,7 @@ int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
                         } else {
                                 rc = load_xattr_datum(c, xd);
                                 if (unlikely(rc > 0)) {
+                                        *pref = ref->next;
                                         delete_xattr_ref(c, ref);
                                         goto retry;
                                 } else if (unlikely(rc < 0)) {
@@ -1053,11 +1066,11 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
         struct jffs2_inode_cache *ic = f->inocache;
         struct jffs2_xattr_datum *xd;
-        struct jffs2_xattr_ref *ref, *newref;
+        struct jffs2_xattr_ref *ref, *newref, **pref;
         uint32_t phys_ofs, length, request;
         int rc;
 
-        rc = check_xattr_ref_ilist(c, ic);
+        rc = check_xattr_ref_inode(c, ic);
         if (unlikely(rc))
                 return rc;
 
@@ -1072,13 +1085,14 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
         /* Find existing xattr */
         down_write(&c->xattr_sem);
  retry:
-        list_for_each_entry(ref, &ic->ilist, ilist) {
+        for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
                 xd = ref->xd;
                 if (xd->xprefix != xprefix)
                         continue;
                 if (!xd->xname) {
                         rc = load_xattr_datum(c, xd);
                         if (unlikely(rc > 0)) {
+                                *pref = ref->next;
                                 delete_xattr_ref(c, ref);
                                 goto retry;
                         } else if (unlikely(rc < 0))
@@ -1090,6 +1104,7 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
                                 goto out;
                         }
                         if (!buffer) {
+                                *pref = ref->next;
                                 delete_xattr_ref(c, ref);
                                 rc = 0;
                                 goto out;
@@ -1098,7 +1113,6 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
                 }
         }
         /* not found */
-        ref = NULL;
         if (flags & XATTR_REPLACE) {
                 rc = -ENODATA;
                 goto out;
@@ -1130,14 +1144,19 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
                 return rc;
         }
         down_write(&c->xattr_sem);
+        if (ref)
+                *pref = ref->next;
         newref = create_xattr_ref(c, ic, xd, phys_ofs);
         if (IS_ERR(newref)) {
+                if (ref) {
+                        ref->next = ic->xref;
+                        ic->xref = ref;
+                }
                 rc = PTR_ERR(newref);
                 xd->refcnt--;
                 if (!xd->refcnt)
                         delete_xattr_datum(c, xd);
         } else if (ref) {
-                /* If replaced xattr_ref exists */
                 delete_xattr_ref(c, ref);
         }
  out:
diff --git a/fs/jffs2/xattr.h b/fs/jffs2/xattr.h
index d157ad641ed4..0360097e5933 100644
--- a/fs/jffs2/xattr.h
+++ b/fs/jffs2/xattr.h
@@ -54,7 +54,7 @@ struct jffs2_xattr_ref
                 struct jffs2_xattr_datum *xd;   /* reference to jffs2_xattr_datum */
                 uint32_t xid;                   /* only used in sccanning/building */
         };
-        struct list_head ilist;                 /* chained from ic->ilist */
+        struct jffs2_xattr_ref *next;           /* chained from ic->xref_list */
 };
 
 #ifdef CONFIG_JFFS2_FS_XATTR
@@ -86,9 +86,6 @@ extern ssize_t jffs2_listxattr(struct dentry *, char *, size_t);
 #define jffs2_setxattr          generic_setxattr
 #define jffs2_removexattr       generic_removexattr
 
-/*---- Any inline initialize functions ----*/
-#define init_xattr_inode_cache(x) INIT_LIST_HEAD(&((x)->ilist))
-
 #else
 
 #define jffs2_init_xattr_subsystem(c)
@@ -106,8 +103,6 @@ extern ssize_t jffs2_listxattr(struct dentry *, char *, size_t);
 #define jffs2_setxattr          NULL
 #define jffs2_removexattr       NULL
 
-#define init_xattr_inode_cache(x)
-
 #endif /* CONFIG_JFFS2_FS_XATTR */
 
 #ifdef CONFIG_JFFS2_FS_SECURITY