[15/33] pnfsblock: lseg alloc and free

Commit Message

Jim Rees June 14, 2011, 2:32 a.m. UTC

From: Fred Isaman <[e-mail]>

Signed-off-by: Fred Isaman <[e-mail]>
[pnfsblock: fix bug getting pnfs_layout_type in translate_devid().]
Signed-off-by: Tao Guo <[e-mail]>
Signed-off-by: Benny Halevy <[e-mail]>
Signed-off-by: Zhang Jingwang <[e-mail]>
---
 fs/nfs/blocklayout/blocklayout.c    |   39 +++++++++++++++++++++++++++++-----
 fs/nfs/blocklayout/blocklayout.h    |    6 +++++
 fs/nfs/blocklayout/blocklayoutdev.c |    8 +++++++
 3 files changed, 47 insertions(+), 6 deletions(-)

Patch

diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 4ca0838..992fd31 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -110,16 +110,43 @@  static struct pnfs_layout_hdr *bl_alloc_layout_hdr(struct inode *inode,
 	return &bl->bl_layout;
 }
 
-static void
-bl_free_lseg(struct pnfs_layout_segment *lseg)
+static void bl_free_lseg(struct pnfs_layout_segment *lseg)
 {
+	dprintk("%s enter\n", __func__);
+	kfree(lseg);
 }
 
-static struct pnfs_layout_segment *
-bl_alloc_lseg(struct pnfs_layout_hdr *lo,
-	      struct nfs4_layoutget_res *lgr, gfp_t gfp_flags)
+/* Because the generic infrastructure does not correctly merge layouts,
+ * we pretty much ignore lseg, and store all data layout wide, so we
+ * can correctly merge.  Eventually we should push some correct merge
+ * behavior up to the generic code, as the current behavior tends to
+ * cause lots of unnecessary overlapping LAYOUTGET requests.
+ */
+static struct pnfs_layout_segment *bl_alloc_lseg(struct pnfs_layout_hdr *lo,
+						 struct nfs4_layoutget_res *lgr,
+						 gfp_t gfp_flags)
 {
-	return NULL;
+	struct pnfs_layout_segment *lseg;
+	int status;
+
+	dprintk("%s enter\n", __func__);
+	lseg = kzalloc(sizeof(*lseg) + 0, gfp_flags);
+	if (!lseg)
+		return NULL;
+	status = nfs4_blk_process_layoutget(lo, lgr, gfp_flags);
+	if (status) {
+		/* We don't want to call the full-blown bl_free_lseg,
+		 * since on error extents were not touched.
+		 */
+		/* STUB - we really want to distinguish between 2 error
+		 * conditions here.  This lseg failed, but lo data structures
+		 * are OK, or we hosed the lo data structures.  The calling
+		 * code probably needs to distinguish this too.
+		 */
+		kfree(lseg);
+		return ERR_PTR(status);
+	}
+	return lseg;
 }
 
 static void
diff --git a/fs/nfs/blocklayout/blocklayout.h b/fs/nfs/blocklayout/blocklayout.h
index 839b81d..5c1ccc1 100644
--- a/fs/nfs/blocklayout/blocklayout.h
+++ b/fs/nfs/blocklayout/blocklayout.h
@@ -93,6 +93,12 @@  static inline struct pnfs_block_layout *BLK_LO2EXT(struct pnfs_layout_hdr *lo)
 	return container_of(lo, struct pnfs_block_layout, bl_layout);
 }
 
+static inline struct pnfs_block_layout *
+BLK_LSEG2EXT(struct pnfs_layout_segment *lseg)
+{
+	return BLK_LO2EXT(lseg->pls_layout);
+}
+
 /* blocklayoutdev.c */
 struct block_device *nfs4_blkdev_get(dev_t dev);
 int nfs4_blkdev_put(struct block_device *bdev);
diff --git a/fs/nfs/blocklayout/blocklayoutdev.c b/fs/nfs/blocklayout/blocklayoutdev.c
index 9a65a66..0fedf50 100644
--- a/fs/nfs/blocklayout/blocklayoutdev.c
+++ b/fs/nfs/blocklayout/blocklayoutdev.c
@@ -149,3 +149,11 @@  out_err:
 		kfree(msg);
 	return NULL;
 }
+
+int
+nfs4_blk_process_layoutget(struct pnfs_layout_hdr *lo,
+			   struct nfs4_layoutget_res *lgr, gfp_t gfp_flags)
+{
+	/* STUB */
+	return -EIO;
+}