UBI: factorize code used to manipulate volumes at attach time

Volume creation/search code is duplicated in a few places (fastmap and
non fastmap code). Create some helpers to factorize the code.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

diff --git a/drivers/mtd/ubi/attach.c b/drivers/mtd/ubi/attach.c
index 95138ae2062f58341de41fff97150f746e742f1c..6d34cd7b0263578f636dac95967f50727ff5cc63 100644 (file)
--- a/drivers/mtd/ubi/attach.c
+++ b/drivers/mtd/ubi/attach.c
@@ -95,6 +95,92 @@ static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai);
 static struct ubi_ec_hdr *ech;
 static struct ubi_vid_hdr *vidh;
 
+#define AV_FIND                BIT(0)
+#define AV_ADD         BIT(1)
+#define AV_FIND_OR_ADD (AV_FIND | AV_ADD)
+
+/**
+ * find_or_add_av - internal function to find a volume, add a volume or do
+ *                 both (find and add if missing).
+ * @ai: attaching information
+ * @vol_id: the requested volume ID
+ * @flags: a combination of the %AV_FIND and %AV_ADD flags describing the
+ *        expected operation. If only %AV_ADD is set, -EEXIST is returned
+ *        if the volume already exists. If only %AV_FIND is set, NULL is
+ *        returned if the volume does not exist. And if both flags are
+ *        set, the helper first tries to find an existing volume, and if
+ *        it does not exist it creates a new one.
+ * @created: in value used to inform the caller whether it"s a newly created
+ *          volume or not.
+ *
+ * This function returns a pointer to a volume description or an ERR_PTR if
+ * the operation failed. It can also return NULL if only %AV_FIND is set and
+ * the volume does not exist.
+ */
+static struct ubi_ainf_volume *find_or_add_av(struct ubi_attach_info *ai,
+                                             int vol_id, unsigned int flags,
+                                             bool *created)
+{
+       struct ubi_ainf_volume *av;
+       struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
+
+       /* Walk the volume RB-tree to look if this volume is already present */
+       while (*p) {
+               parent = *p;
+               av = rb_entry(parent, struct ubi_ainf_volume, rb);
+
+               if (vol_id == av->vol_id) {
+                       *created = false;
+
+                       if (!(flags & AV_FIND))
+                               return ERR_PTR(-EEXIST);
+
+                       return av;
+               }
+
+               if (vol_id > av->vol_id)
+                       p = &(*p)->rb_left;
+               else
+                       p = &(*p)->rb_right;
+       }
+
+       if (!(flags & AV_ADD))
+               return NULL;
+
+       /* The volume is absent - add it */
+       av = kzalloc(sizeof(*av), GFP_KERNEL);
+       if (!av)
+               return ERR_PTR(-ENOMEM);
+
+       av->vol_id = vol_id;
+
+       if (vol_id > ai->highest_vol_id)
+               ai->highest_vol_id = vol_id;
+
+       rb_link_node(&av->rb, parent, p);
+       rb_insert_color(&av->rb, &ai->volumes);
+       ai->vols_found += 1;
+       *created = true;
+       dbg_bld("added volume %d", vol_id);
+       return av;
+}
+
+/**
+ * ubi_find_or_add_av - search for a volume in the attaching information and
+ *                     add one if it does not exist.
+ * @ai: attaching information
+ * @vol_id: the requested volume ID
+ * @created: whether the volume has been created or not
+ *
+ * This function returns a pointer to the new volume description or an
+ * ERR_PTR if the operation failed.
+ */
+static struct ubi_ainf_volume *ubi_find_or_add_av(struct ubi_attach_info *ai,
+                                                 int vol_id, bool *created)
+{
+       return find_or_add_av(ai, vol_id, AV_FIND_OR_ADD, created);
+}
+
 /**
  * add_to_list - add physical eraseblock to a list.
  * @ai: attaching information
@@ -294,44 +380,20 @@ static struct ubi_ainf_volume *add_volume(struct ubi_attach_info *ai,
                                          const struct ubi_vid_hdr *vid_hdr)
 {
        struct ubi_ainf_volume *av;
-       struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
+       bool created;
 
        ubi_assert(vol_id == be32_to_cpu(vid_hdr->vol_id));
 
-       /* Walk the volume RB-tree to look if this volume is already present */
-       while (*p) {
-               parent = *p;
-               av = rb_entry(parent, struct ubi_ainf_volume, rb);
-
-               if (vol_id == av->vol_id)
-                       return av;
+       av = ubi_find_or_add_av(ai, vol_id, &created);
+       if (IS_ERR(av) || !created)
+               return av;
 
-               if (vol_id > av->vol_id)
-                       p = &(*p)->rb_left;
-               else
-                       p = &(*p)->rb_right;
-       }
-
-       /* The volume is absent - add it */
-       av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
-       if (!av)
-               return ERR_PTR(-ENOMEM);
-
-       av->highest_lnum = av->leb_count = 0;
-       av->vol_id = vol_id;
-       av->root = RB_ROOT;
        av->used_ebs = be32_to_cpu(vid_hdr->used_ebs);
        av->data_pad = be32_to_cpu(vid_hdr->data_pad);
        av->compat = vid_hdr->compat;
        av->vol_type = vid_hdr->vol_type == UBI_VID_DYNAMIC ? UBI_DYNAMIC_VOLUME
                                                            : UBI_STATIC_VOLUME;
-       if (vol_id > ai->highest_vol_id)
-               ai->highest_vol_id = vol_id;
 
-       rb_link_node(&av->rb, parent, p);
-       rb_insert_color(&av->rb, &ai->volumes);
-       ai->vols_found += 1;
-       dbg_bld("added volume %d", vol_id);
        return av;
 }
 
@@ -628,6 +690,21 @@ int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
        return 0;
 }
 
+/**
+ * ubi_add_av - add volume to the attaching information.
+ * @ai: attaching information
+ * @vol_id: the requested volume ID
+ *
+ * This function returns a pointer to the new volume description or an
+ * ERR_PTR if the operation failed.
+ */
+struct ubi_ainf_volume *ubi_add_av(struct ubi_attach_info *ai, int vol_id)
+{
+       bool created;
+
+       return find_or_add_av(ai, vol_id, AV_ADD, &created);
+}
+
 /**
  * ubi_find_av - find volume in the attaching information.
  * @ai: attaching information
@@ -639,22 +716,10 @@ int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
 struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
                                    int vol_id)
 {
-       struct ubi_ainf_volume *av;
-       struct rb_node *p = ai->volumes.rb_node;
-
-       while (p) {
-               av = rb_entry(p, struct ubi_ainf_volume, rb);
-
-               if (vol_id == av->vol_id)
-                       return av;
-
-               if (vol_id > av->vol_id)
-                       p = p->rb_left;
-               else
-                       p = p->rb_right;
-       }
+       bool created;
 
-       return NULL;
+       return find_or_add_av((struct ubi_attach_info *)ai, vol_id, AV_FIND,
+                             &created);
 }
 
 /**

diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
index a6ed78d14055e5a0205258ac1d11bc932df30f0c..bae80699c2f285507e6f1808259900756eb9ece1 100644 (file)
--- a/drivers/mtd/ubi/fastmap.c
+++ b/drivers/mtd/ubi/fastmap.c
@@ -186,40 +186,19 @@ static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
                                       int last_eb_bytes)
 {
        struct ubi_ainf_volume *av;
-       struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 
-       while (*p) {
-               parent = *p;
-               av = rb_entry(parent, struct ubi_ainf_volume, rb);
-
-               if (vol_id > av->vol_id)
-                       p = &(*p)->rb_left;
-               else if (vol_id < av->vol_id)
-                       p = &(*p)->rb_right;
-               else
-                       return ERR_PTR(-EINVAL);
-       }
+       av = ubi_add_av(ai, vol_id);
+       if (IS_ERR(av))
+               return av;
 
-       av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
-       if (!av)
-               goto out;
-
-       av->highest_lnum = av->leb_count = av->used_ebs = 0;
-       av->vol_id = vol_id;
        av->data_pad = data_pad;
        av->last_data_size = last_eb_bytes;
        av->compat = 0;
        av->vol_type = vol_type;
-       av->root = RB_ROOT;
        if (av->vol_type == UBI_STATIC_VOLUME)
                av->used_ebs = used_ebs;
 
        dbg_bld("found volume (ID %i)", vol_id);
-
-       rb_link_node(&av->rb, parent, p);
-       rb_insert_color(&av->rb, &ai->volumes);
-
-out:
        return av;
 }
 

diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index b616a115c9d38b9e8f2d5b3209629f1e98ab0501..fce142666bf326f5d8988015b38448a867064b8d 100644 (file)
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -794,6 +794,7 @@ extern struct blocking_notifier_head ubi_notifiers;
 /* attach.c */
 int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
                  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
+struct ubi_ainf_volume *ubi_add_av(struct ubi_attach_info *ai, int vol_id);
 struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
                                    int vol_id);
 void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av);