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-rw-r--r--fs/nfs/blocklayout/extents.c210
1 files changed, 210 insertions, 0 deletions
diff --git a/fs/nfs/blocklayout/extents.c b/fs/nfs/blocklayout/extents.c
index 84bf2408772..7521940dcca 100644
--- a/fs/nfs/blocklayout/extents.c
+++ b/fs/nfs/blocklayout/extents.c
@@ -329,6 +329,73 @@ static void print_clist(struct list_head *list, unsigned int count)
}
}
+/* Note: In theory, we should do more checking that devid's match between
+ * old and new, but if they don't, the lists are too corrupt to salvage anyway.
+ */
+/* Note this is very similar to bl_add_merge_extent */
+static void add_to_commitlist(struct pnfs_block_layout *bl,
+ struct pnfs_block_short_extent *new)
+{
+ struct list_head *clist = &bl->bl_commit;
+ struct pnfs_block_short_extent *old, *save;
+ sector_t end = new->bse_f_offset + new->bse_length;
+
+ dprintk("%s enter\n", __func__);
+ print_short_extent(new);
+ print_clist(clist, bl->bl_count);
+ bl->bl_count++;
+ /* Scan for proper place to insert, extending new to the left
+ * as much as possible.
+ */
+ list_for_each_entry_safe(old, save, clist, bse_node) {
+ if (new->bse_f_offset < old->bse_f_offset)
+ break;
+ if (end <= old->bse_f_offset + old->bse_length) {
+ /* Range is already in list */
+ bl->bl_count--;
+ kfree(new);
+ return;
+ } else if (new->bse_f_offset <=
+ old->bse_f_offset + old->bse_length) {
+ /* new overlaps or abuts existing be */
+ if (new->bse_mdev == old->bse_mdev) {
+ /* extend new to fully replace old */
+ new->bse_length += new->bse_f_offset -
+ old->bse_f_offset;
+ new->bse_f_offset = old->bse_f_offset;
+ list_del(&old->bse_node);
+ bl->bl_count--;
+ kfree(old);
+ }
+ }
+ }
+ /* Note that if we never hit the above break, old will not point to a
+ * valid extent. However, in that case &old->bse_node==list.
+ */
+ list_add_tail(&new->bse_node, &old->bse_node);
+ /* Scan forward for overlaps. If we find any, extend new and
+ * remove the overlapped extent.
+ */
+ old = list_prepare_entry(new, clist, bse_node);
+ list_for_each_entry_safe_continue(old, save, clist, bse_node) {
+ if (end < old->bse_f_offset)
+ break;
+ /* new overlaps or abuts old */
+ if (new->bse_mdev == old->bse_mdev) {
+ if (end < old->bse_f_offset + old->bse_length) {
+ /* extend new to fully cover old */
+ end = old->bse_f_offset + old->bse_length;
+ new->bse_length = end - new->bse_f_offset;
+ }
+ list_del(&old->bse_node);
+ bl->bl_count--;
+ kfree(old);
+ }
+ }
+ dprintk("%s: after merging\n", __func__);
+ print_clist(clist, bl->bl_count);
+}
+
static void print_bl_extent(struct pnfs_block_extent *be)
{
dprintk("PRINT EXTENT extent %p\n", be);
@@ -539,6 +606,34 @@ bl_find_get_extent(struct pnfs_block_layout *bl, sector_t isect,
return ret;
}
+/* Similar to bl_find_get_extent, but called with lock held, and ignores cow */
+static struct pnfs_block_extent *
+bl_find_get_extent_locked(struct pnfs_block_layout *bl, sector_t isect)
+{
+ struct pnfs_block_extent *be, *ret = NULL;
+ int i;
+
+ dprintk("%s enter with isect %llu\n", __func__, (u64)isect);
+ for (i = 0; i < EXTENT_LISTS; i++) {
+ if (ret)
+ break;
+ list_for_each_entry_reverse(be, &bl->bl_extents[i], be_node) {
+ if (isect >= be->be_f_offset + be->be_length)
+ break;
+ if (isect >= be->be_f_offset) {
+ /* We have found an extent */
+ dprintk("%s Get %p (%i)\n", __func__, be,
+ atomic_read(&be->be_refcnt.refcount));
+ kref_get(&be->be_refcnt);
+ ret = be;
+ break;
+ }
+ }
+ }
+ print_bl_extent(ret);
+ return ret;
+}
+
int
encode_pnfs_block_layoutupdate(struct pnfs_block_layout *bl,
struct xdr_stream *xdr,
@@ -628,3 +723,118 @@ _front_merge(struct pnfs_block_extent *be, struct list_head *head,
kfree(storage);
return be;
}
+
+static u64
+set_to_rw(struct pnfs_block_layout *bl, u64 offset, u64 length)
+{
+ u64 rv = offset + length;
+ struct pnfs_block_extent *be, *e1, *e2, *e3, *new, *old;
+ struct pnfs_block_extent *children[3];
+ struct pnfs_block_extent *merge1 = NULL, *merge2 = NULL;
+ int i = 0, j;
+
+ dprintk("%s(%llu, %llu)\n", __func__, offset, length);
+ /* Create storage for up to three new extents e1, e2, e3 */
+ e1 = kmalloc(sizeof(*e1), GFP_ATOMIC);
+ e2 = kmalloc(sizeof(*e2), GFP_ATOMIC);
+ e3 = kmalloc(sizeof(*e3), GFP_ATOMIC);
+ /* BUG - we are ignoring any failure */
+ if (!e1 || !e2 || !e3)
+ goto out_nosplit;
+
+ spin_lock(&bl->bl_ext_lock);
+ be = bl_find_get_extent_locked(bl, offset);
+ rv = be->be_f_offset + be->be_length;
+ if (be->be_state != PNFS_BLOCK_INVALID_DATA) {
+ spin_unlock(&bl->bl_ext_lock);
+ goto out_nosplit;
+ }
+ /* Add e* to children, bumping e*'s krefs */
+ if (be->be_f_offset != offset) {
+ _prep_new_extent(e1, be, be->be_f_offset,
+ offset - be->be_f_offset,
+ PNFS_BLOCK_INVALID_DATA);
+ children[i++] = e1;
+ print_bl_extent(e1);
+ } else
+ merge1 = e1;
+ _prep_new_extent(e2, be, offset,
+ min(length, be->be_f_offset + be->be_length - offset),
+ PNFS_BLOCK_READWRITE_DATA);
+ children[i++] = e2;
+ print_bl_extent(e2);
+ if (offset + length < be->be_f_offset + be->be_length) {
+ _prep_new_extent(e3, be, e2->be_f_offset + e2->be_length,
+ be->be_f_offset + be->be_length -
+ offset - length,
+ PNFS_BLOCK_INVALID_DATA);
+ children[i++] = e3;
+ print_bl_extent(e3);
+ } else
+ merge2 = e3;
+
+ /* Remove be from list, and insert the e* */
+ /* We don't get refs on e*, since this list is the base reference
+ * set when init'ed.
+ */
+ if (i < 3)
+ children[i] = NULL;
+ new = children[0];
+ list_replace(&be->be_node, &new->be_node);
+ bl_put_extent(be);
+ new = _front_merge(new, &bl->bl_extents[RW_EXTENT], merge1);
+ for (j = 1; j < i; j++) {
+ old = new;
+ new = children[j];
+ list_add(&new->be_node, &old->be_node);
+ }
+ if (merge2) {
+ /* This is a HACK, should just create a _back_merge function */
+ new = list_entry(new->be_node.next,
+ struct pnfs_block_extent, be_node);
+ new = _front_merge(new, &bl->bl_extents[RW_EXTENT], merge2);
+ }
+ spin_unlock(&bl->bl_ext_lock);
+
+ /* Since we removed the base reference above, be is now scheduled for
+ * destruction.
+ */
+ bl_put_extent(be);
+ dprintk("%s returns %llu after split\n", __func__, rv);
+ return rv;
+
+ out_nosplit:
+ kfree(e1);
+ kfree(e2);
+ kfree(e3);
+ dprintk("%s returns %llu without splitting\n", __func__, rv);
+ return rv;
+}
+
+void
+clean_pnfs_block_layoutupdate(struct pnfs_block_layout *bl,
+ const struct nfs4_layoutcommit_args *arg,
+ int status)
+{
+ struct pnfs_block_short_extent *lce, *save;
+
+ dprintk("%s status %d\n", __func__, status);
+ list_for_each_entry_safe(lce, save, &bl->bl_committing, bse_node) {
+ if (likely(!status)) {
+ u64 offset = lce->bse_f_offset;
+ u64 end = offset + lce->bse_length;
+
+ do {
+ offset = set_to_rw(bl, offset, end - offset);
+ } while (offset < end);
+ list_del(&lce->bse_node);
+
+ kfree(lce);
+ } else {
+ list_del(&lce->bse_node);
+ spin_lock(&bl->bl_ext_lock);
+ add_to_commitlist(bl, lce);
+ spin_unlock(&bl->bl_ext_lock);
+ }
+ }
+}