[JFFS2] Reduce visibility of raw_node_ref to upper layers of JFFS2 code.

As the first step towards eliminating the ref->next_phys member and saving memory by using an _array_ of struct jffs2_raw_node_ref per eraseblock, stop the write functions from allocating their own refs; have them just _reserve_ the appropriate number instead. Then jffs2_link_node_ref() can just fill them in. Use a linked list of pre-allocated refs in the superblock, for now. Once we switch to an array, it'll just be a case of extending that array. Signed-off-by: David Woodhouse <[email protected]>
iegor · May 24, 2006 · 2f78540 · 2f78540
1 parent 4cbb9b8
commit 2f78540
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Showing 12 changed files with 204 additions and 349 deletions.
diff --git a/fs/jffs2/erase.c b/fs/jffs2/erase.c
@@ -296,7 +296,7 @@ void jffs2_free_all_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *
 			jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
 		/* else it was a non-inode node or already removed, so don't bother */
 
-		jffs2_free_raw_node_ref(ref);
+		__jffs2_free_raw_node_ref(ref);
 	}
 	jeb->last_node = NULL;
 }
@@ -351,7 +351,6 @@ static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_erasebl
 
 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
 {
-	struct jffs2_raw_node_ref *marker_ref = NULL;
 	size_t retlen;
 	int ret;
 	uint32_t bad_offset;
@@ -384,11 +383,7 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
 			.totlen =	cpu_to_je32(c->cleanmarker_size)
 		};
 
-		marker_ref = jffs2_alloc_raw_node_ref();
-		if (!marker_ref) {
-			printk(KERN_WARNING "Failed to allocate raw node ref for clean marker. Refiling\n");
-			goto refile;
-		}
+		jffs2_prealloc_raw_node_refs(c, 1);
 
 		marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
 
@@ -404,16 +399,13 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
 				printk(KERN_WARNING "Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
 				       jeb->offset, sizeof(marker), retlen);
 
-			jffs2_free_raw_node_ref(marker_ref);
 			goto filebad;
 		}
 
 		/* Everything else got zeroed before the erase */
 		jeb->free_size = c->sector_size;
-
-		marker_ref->flash_offset = jeb->offset | REF_NORMAL;
-
-		jffs2_link_node_ref(c, jeb, marker_ref, c->cleanmarker_size, NULL);
+		/* FIXME Special case for cleanmarker in empty block */
+		jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
 	}
 
 	spin_lock(&c->erase_completion_lock);

diff --git a/fs/jffs2/gc.c b/fs/jffs2/gc.c
@@ -528,7 +528,6 @@ static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
 					  struct jffs2_raw_node_ref *raw)
 {
 	union jffs2_node_union *node;
-	struct jffs2_raw_node_ref *nraw;
 	size_t retlen;
 	int ret;
 	uint32_t phys_ofs, alloclen;
@@ -618,30 +617,21 @@ static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
 		}
 	}
 
-	nraw = jffs2_alloc_raw_node_ref();
-	if (!nraw) {
-		ret = -ENOMEM;
-		goto out_node;
-	}
-
 	/* OK, all the CRCs are good; this node can just be copied as-is. */
  retry:
-	nraw->flash_offset = phys_ofs = write_ofs(c);
+	phys_ofs = write_ofs(c);
 
 	ret = jffs2_flash_write(c, phys_ofs, rawlen, &retlen, (char *)node);
 
 	if (ret || (retlen != rawlen)) {
 		printk(KERN_NOTICE "Write of %d bytes at 0x%08x failed. returned %d, retlen %zd\n",
-                       rawlen, nraw->flash_offset, ret, retlen);
+                       rawlen, phys_ofs, ret, retlen);
 		if (retlen) {
-			nraw->flash_offset |= REF_OBSOLETE;
-			jffs2_add_physical_node_ref(c, nraw, rawlen, NULL);
-			jffs2_mark_node_obsolete(c, nraw);
+			jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, rawlen, NULL);
 		} else {
-			printk(KERN_NOTICE "Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n", nraw->flash_offset);
-                        jffs2_free_raw_node_ref(nraw);
+			printk(KERN_NOTICE "Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n", phys_ofs);
 		}
-		if (!retried && (nraw = jffs2_alloc_raw_node_ref())) {
+		if (!retried) {
 			/* Try to reallocate space and retry */
 			uint32_t dummy;
 			struct jffs2_eraseblock *jeb = &c->blocks[phys_ofs / c->sector_size];
@@ -666,16 +656,13 @@ static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
 				goto retry;
 			}
 			D1(printk(KERN_DEBUG "Failed to allocate space to retry failed write: %d!\n", ret));
-			jffs2_free_raw_node_ref(nraw);
 		}
 
-		jffs2_free_raw_node_ref(nraw);
 		if (!ret)
 			ret = -EIO;
 		goto out_node;
 	}
-	nraw->flash_offset |= REF_PRISTINE;
-	jffs2_add_physical_node_ref(c, nraw, rawlen, ic);
+	jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, rawlen, ic);
 
 	jffs2_mark_node_obsolete(c, raw);
 	D1(printk(KERN_DEBUG "WHEEE! GC REF_PRISTINE node at 0x%08x succeeded\n", ref_offset(raw)));

diff --git a/fs/jffs2/jffs2_fs_sb.h b/fs/jffs2/jffs2_fs_sb.h
@@ -26,6 +26,9 @@ struct jffs2_inodirty;
 struct jffs2_sb_info {
 	struct mtd_info *mtd;
 
+	struct jffs2_raw_node_ref *refs;
+	int reserved_refs;
+
 	uint32_t highest_ino;
 	uint32_t checked_ino;
 

diff --git a/fs/jffs2/malloc.c b/fs/jffs2/malloc.c
@@ -190,15 +190,37 @@ void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *x)
 	kmem_cache_free(tmp_dnode_info_slab, x);
 }
 
-struct jffs2_raw_node_ref *jffs2_alloc_raw_node_ref(void)
+int jffs2_prealloc_raw_node_refs(struct jffs2_sb_info *c, int nr)
+{
+	struct jffs2_raw_node_ref *p = c->refs;
+
+	dbg_memalloc("%d\n", nr);
+
+	while (nr && p) {
+		p = p->next_in_ino;
+		nr--;
+	}
+	while (nr) {
+		p = __jffs2_alloc_raw_node_ref();
+		if (!p)
+			return -ENOMEM;
+		p->next_in_ino = c->refs;
+		c->refs = p;
+		nr--;
+	}
+	c->reserved_refs = nr;
+	return 0;
+}
+
+struct jffs2_raw_node_ref *__jffs2_alloc_raw_node_ref(void)
 {
 	struct jffs2_raw_node_ref *ret;
 	ret = kmem_cache_alloc(raw_node_ref_slab, GFP_KERNEL);
 	dbg_memalloc("%p\n", ret);
 	return ret;
 }
 
-void jffs2_free_raw_node_ref(struct jffs2_raw_node_ref *x)
+void __jffs2_free_raw_node_ref(struct jffs2_raw_node_ref *x)
 {
 	dbg_memalloc("%p\n", x);
 	kmem_cache_free(raw_node_ref_slab, x);

diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c
@@ -953,13 +953,19 @@ void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
 
 	for (i=0; i<c->nr_blocks; i++) {
 		this = c->blocks[i].first_node;
-		while(this) {
+		while (this) {
 			next = this->next_phys;
-			jffs2_free_raw_node_ref(this);
+			__jffs2_free_raw_node_ref(this);
 			this = next;
 		}
 		c->blocks[i].first_node = c->blocks[i].last_node = NULL;
 	}
+	this = c->refs;
+	while (this) {
+		next = this->next_in_ino;
+		__jffs2_free_raw_node_ref(this);
+		this = next;
+	}
 }
 
 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
@@ -1047,10 +1053,27 @@ void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
 	}
 }
 
-void jffs2_link_node_ref(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
-			 struct jffs2_raw_node_ref *ref, uint32_t len,
-			 struct jffs2_inode_cache *ic)
+struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
+					       struct jffs2_eraseblock *jeb,
+					       uint32_t ofs, uint32_t len,
+					       struct jffs2_inode_cache *ic)
 {
+	struct jffs2_raw_node_ref *ref;
+
+	/* These will be preallocated _very_ shortly. */
+	ref = c->refs;
+	if (!c->refs) {
+		JFFS2_WARNING("Using non-preallocated refs!\n");
+		ref = __jffs2_alloc_raw_node_ref();
+		BUG_ON(!ref);
+		WARN_ON(1);
+	} else {
+		c->refs = ref->next_in_ino;
+	}
+
+	ref->next_phys = NULL;
+	ref->flash_offset = ofs;
+
 	if (!jeb->first_node)
 		jeb->first_node = ref;
 	if (jeb->last_node) {
@@ -1093,15 +1116,15 @@ void jffs2_link_node_ref(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 	c->free_size -= len;
 	jeb->free_size -= len;
 
-	ref->next_phys = NULL;
 #ifdef TEST_TOTLEN
 	/* Set (and test) __totlen field... for now */
 	ref->__totlen = len;
 	ref_totlen(c, jeb, ref);
 #endif
+	return ref;
 }
 
-/* No locking. Do not use on a live file system */
+/* No locking, no reservation of 'ref'. Do not use on a live file system */
 int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 			   uint32_t size)
 {
@@ -1121,18 +1144,10 @@ int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb
 		jeb->dirty_size += size;
 		jeb->free_size -= size;
 	} else {
-		struct jffs2_raw_node_ref *ref;
-		ref = jffs2_alloc_raw_node_ref();
-		if (!ref)
-			return -ENOMEM;
-
-		ref->flash_offset = jeb->offset + c->sector_size - jeb->free_size;
-		ref->flash_offset |= REF_OBSOLETE;
-#ifdef TEST_TOTLEN
-		ref->__totlen = size;
-#endif
+		uint32_t ofs = jeb->offset + c->sector_size - jeb->free_size;
+		ofs |= REF_OBSOLETE;
 
-		jffs2_link_node_ref(c, jeb, ref, size, NULL);
+		jffs2_link_node_ref(c, jeb, ofs, size, NULL);
 	}
 
 	return 0;

diff --git a/fs/jffs2/nodelist.h b/fs/jffs2/nodelist.h
@@ -318,9 +318,10 @@ void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *t
 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn);
 void jffs2_truncate_fragtree (struct jffs2_sb_info *c, struct rb_root *list, uint32_t size);
 int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn);
-void jffs2_link_node_ref(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
-			 struct jffs2_raw_node_ref *ref, uint32_t len,
-			 struct jffs2_inode_cache *ic);
+struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
+					       struct jffs2_eraseblock *jeb,
+					       uint32_t ofs, uint32_t len,
+					       struct jffs2_inode_cache *ic);
 extern uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c,
 				   struct jffs2_eraseblock *jeb,
 				   struct jffs2_raw_node_ref *ref);
@@ -331,10 +332,9 @@ int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
 			uint32_t *len, int prio, uint32_t sumsize);
 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
 			uint32_t *len, uint32_t sumsize);
-int jffs2_add_physical_node_ref(struct jffs2_sb_info *c, 
-				struct jffs2_raw_node_ref *new,
-				uint32_t len,
-				struct jffs2_inode_cache *ic);
+struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c, 
+						       uint32_t ofs, uint32_t len,
+						       struct jffs2_inode_cache *ic);
 void jffs2_complete_reservation(struct jffs2_sb_info *c);
 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *raw);
 
@@ -378,8 +378,9 @@ struct jffs2_raw_inode *jffs2_alloc_raw_inode(void);
 void jffs2_free_raw_inode(struct jffs2_raw_inode *);
 struct jffs2_tmp_dnode_info *jffs2_alloc_tmp_dnode_info(void);
 void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *);
-struct jffs2_raw_node_ref *jffs2_alloc_raw_node_ref(void);
-void jffs2_free_raw_node_ref(struct jffs2_raw_node_ref *);
+int jffs2_prealloc_raw_node_refs(struct jffs2_sb_info *c, int nr);
+struct jffs2_raw_node_ref *__jffs2_alloc_raw_node_ref(void);
+void __jffs2_free_raw_node_ref(struct jffs2_raw_node_ref *);
 struct jffs2_node_frag *jffs2_alloc_node_frag(void);
 void jffs2_free_node_frag(struct jffs2_node_frag *);
 struct jffs2_inode_cache *jffs2_alloc_inode_cache(void);

diff --git a/fs/jffs2/nodemgmt.c b/fs/jffs2/nodemgmt.c
@@ -137,6 +137,8 @@ int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
 		}
 	}
 	spin_unlock(&c->erase_completion_lock);
+	if (!ret)
+		ret = jffs2_prealloc_raw_node_refs(c, 1);
 	if (ret)
 		up(&c->alloc_sem);
 	return ret;
@@ -158,6 +160,9 @@ int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
 		}
 	}
 	spin_unlock(&c->erase_completion_lock);
+	if (!ret)
+		ret = jffs2_prealloc_raw_node_refs(c, 1);
+
 	return ret;
 }
 
@@ -381,30 +386,30 @@ static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
  *	Must be called with the alloc_sem held.
  */
 
-int jffs2_add_physical_node_ref(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *new,
-				uint32_t len, struct jffs2_inode_cache *ic)
+struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c,
+						       uint32_t ofs, uint32_t len,
+						       struct jffs2_inode_cache *ic)
 {
 	struct jffs2_eraseblock *jeb;
+	struct jffs2_raw_node_ref *new;
 
-	jeb = &c->blocks[new->flash_offset / c->sector_size];
-#ifdef TEST_TOTLEN
-	new->__totlen = len;
-#endif
+	jeb = &c->blocks[ofs / c->sector_size];
 
-	D1(printk(KERN_DEBUG "jffs2_add_physical_node_ref(): Node at 0x%x(%d), size 0x%x\n", ref_offset(new), ref_flags(new), len));
+	D1(printk(KERN_DEBUG "jffs2_add_physical_node_ref(): Node at 0x%x(%d), size 0x%x\n",
+		  ofs & ~3, ofs & 3, len));
 #if 1
-	/* we could get some obsolete nodes after nextblock was refiled
-	   in wbuf.c */
-	if ((c->nextblock || !ref_obsolete(new))
-	    &&(jeb != c->nextblock || ref_offset(new) != jeb->offset + (c->sector_size - jeb->free_size))) {
+	/* Allow non-obsolete nodes only to be added at the end of c->nextblock, 
+	   if c->nextblock is set. Note that wbuf.c will file obsolete nodes
+	   even after refiling c->nextblock */
+	if ((c->nextblock || ((ofs & 3) != REF_OBSOLETE))
+	    && (jeb != c->nextblock || (ofs & ~3) != jeb->offset + (c->sector_size - jeb->free_size))) {
 		printk(KERN_WARNING "argh. node added in wrong place\n");
-		jffs2_free_raw_node_ref(new);
-		return -EINVAL;
+		return ERR_PTR(-EINVAL);
 	}
 #endif
 	spin_lock(&c->erase_completion_lock);
 
-	jffs2_link_node_ref(c, jeb, new, len, ic);
+	new = jffs2_link_node_ref(c, jeb, ofs, len, ic);
 
 	if (!jeb->free_size && !jeb->dirty_size && !ISDIRTY(jeb->wasted_size)) {
 		/* If it lives on the dirty_list, jffs2_reserve_space will put it there */
@@ -425,7 +430,7 @@ int jffs2_add_physical_node_ref(struct jffs2_sb_info *c, struct jffs2_raw_node_r
 
 	spin_unlock(&c->erase_completion_lock);
 
-	return 0;
+	return new;
 }
 
 
@@ -697,7 +702,7 @@ void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref
 		}
 		spin_unlock(&c->erase_completion_lock);
 
-		jffs2_free_raw_node_ref(n);
+		__jffs2_free_raw_node_ref(n);
 	}
 
 	/* Also merge with the previous node in the list, if there is one
@@ -722,7 +727,7 @@ void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref
 				jeb->gc_node=p;
 			}
 			p->next_phys = ref->next_phys;
-			jffs2_free_raw_node_ref(ref);
+			__jffs2_free_raw_node_ref(ref);
 		}
 		spin_unlock(&c->erase_completion_lock);
 	}