pnfs: let layoutcommit handle a list of lseg

There can be multiple lseg per file, so layoutcommit should be
able to handle it.

[Needed in v3.0]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Peng Tao <peng_tao@emc.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jim Rees <rees@umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 25 insertions, 17 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 079614deca3f..efa6ae822ca8 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5912,9 +5912,15 @@ nfs4_layoutcommit_done(struct rpc_task *task, void *calldata)
 static void nfs4_layoutcommit_release(void *calldata)
 {
         struct nfs4_layoutcommit_data *data = calldata;
+        struct pnfs_layout_segment *lseg, *tmp;
 
         /* Matched by references in pnfs_set_layoutcommit */
-        put_lseg(data->lseg);
+        list_for_each_entry_safe(lseg, tmp, &data->lseg_list, pls_lc_list) {
+                list_del_init(&lseg->pls_lc_list);
+                if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT,
+                                       &lseg->pls_flags))
+                        put_lseg(lseg);
+        }
         put_rpccred(data->cred);
         kfree(data);
 }
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index ab2cb04f8a28..a7e5f17f7776 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -225,6 +225,7 @@ static void
 init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
 {
         INIT_LIST_HEAD(&lseg->pls_list);
+        INIT_LIST_HEAD(&lseg->pls_lc_list);
         atomic_set(&lseg->pls_refcount, 1);
         smp_mb();
         set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
@@ -1356,16 +1357,17 @@ pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
 EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
 
 /*
- * Currently there is only one (whole file) write lseg.
+ * There can be multiple RW segments.
  */
-static struct pnfs_layout_segment *pnfs_list_write_lseg(struct inode *inode)
+static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
 {
-        struct pnfs_layout_segment *lseg, *rv = NULL;
+        struct pnfs_layout_segment *lseg;
 
-        list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list)
-                if (lseg->pls_range.iomode == IOMODE_RW)
-                        rv = lseg;
-        return rv;
+        list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
+                if (lseg->pls_range.iomode == IOMODE_RW &&
+                    test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
+                        list_add(&lseg->pls_lc_list, listp);
+        }
 }
 
 void
@@ -1377,12 +1379,14 @@ pnfs_set_layoutcommit(struct nfs_write_data *wdata)
 
         spin_lock(&nfsi->vfs_inode.i_lock);
         if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
-                /* references matched in nfs4_layoutcommit_release */
-                get_lseg(wdata->lseg);
                 mark_as_dirty = true;
                 dprintk("%s: Set layoutcommit for inode %lu ",
                         __func__, wdata->inode->i_ino);
         }
+        if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &wdata->lseg->pls_flags)) {
+                /* references matched in nfs4_layoutcommit_release */
+                get_lseg(wdata->lseg);
+        }
         if (end_pos > nfsi->layout->plh_lwb)
                 nfsi->layout->plh_lwb = end_pos;
         spin_unlock(&nfsi->vfs_inode.i_lock);
@@ -1409,7 +1413,6 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 {
         struct nfs4_layoutcommit_data *data;
         struct nfs_inode *nfsi = NFS_I(inode);
-        struct pnfs_layout_segment *lseg;
         loff_t end_pos;
         int status = 0;
 
@@ -1426,17 +1429,15 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
                 goto out;
         }
 
+        INIT_LIST_HEAD(&data->lseg_list);
         spin_lock(&inode->i_lock);
         if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
                 spin_unlock(&inode->i_lock);
                 kfree(data);
                 goto out;
         }
-        /*
-         * Currently only one (whole file) write lseg which is referenced
-         * in pnfs_set_layoutcommit and will be found.
-         */
-        lseg = pnfs_list_write_lseg(inode);
+
+        pnfs_list_write_lseg(inode, &data->lseg_list);
 
         end_pos = nfsi->layout->plh_lwb;
         nfsi->layout->plh_lwb = 0;
@@ -1446,7 +1447,6 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
         spin_unlock(&inode->i_lock);
 
         data->args.inode = inode;
-        data->lseg = lseg;
         data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
         nfs_fattr_init(&data->fattr);
         data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 1f5cb47e2a2c..b94f874886ca 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -36,10 +36,12 @@
 enum {
         NFS_LSEG_VALID = 0,     /* cleared when lseg is recalled/returned */
         NFS_LSEG_ROC,           /* roc bit received from server */
+        NFS_LSEG_LAYOUTCOMMIT,  /* layoutcommit bit set for layoutcommit */
 };
 
 struct pnfs_layout_segment {
         struct list_head pls_list;
+        struct list_head pls_lc_list;
         struct pnfs_layout_range pls_range;
         atomic_t pls_refcount;
         unsigned long pls_flags;