1 files changed, 101 insertions, 17 deletions

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 10bf07280f4a..7077521acdf4 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -66,6 +66,10 @@ static struct kmem_cache *nfs_direct_cachep;
 /*
  * This represents a set of asynchronous requests that we're waiting on
  */
+struct nfs_direct_mirror {
+        ssize_t count;
+};
+
 struct nfs_direct_req {
         struct kref             kref;           /* release manager */
 
@@ -78,8 +82,13 @@ struct nfs_direct_req {
         /* completion state */
         atomic_t                io_count;       /* i/os we're waiting for */
         spinlock_t              lock;           /* protect completion state */
+
+        struct nfs_direct_mirror mirrors[NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX];
+        int                     mirror_count;
+
         ssize_t                 count,          /* bytes actually processed */
                                 bytes_left,     /* bytes left to be sent */
+                                io_start,       /* start of IO */
                                 error;          /* any reported error */
         struct completion       completion;     /* wait for i/o completion */
 
@@ -108,26 +117,56 @@ static inline int put_dreq(struct nfs_direct_req *dreq)
         return atomic_dec_and_test(&dreq->io_count);
 }
 
+void nfs_direct_set_resched_writes(struct nfs_direct_req *dreq)
+{
+        dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
+}
+EXPORT_SYMBOL_GPL(nfs_direct_set_resched_writes);
+
+static void
+nfs_direct_good_bytes(struct nfs_direct_req *dreq, struct nfs_pgio_header *hdr)
+{
+        int i;
+        ssize_t count;
+
+        WARN_ON_ONCE(hdr->pgio_mirror_idx >= dreq->mirror_count);
+
+        count = dreq->mirrors[hdr->pgio_mirror_idx].count;
+        if (count + dreq->io_start < hdr->io_start + hdr->good_bytes) {
+                count = hdr->io_start + hdr->good_bytes - dreq->io_start;
+                dreq->mirrors[hdr->pgio_mirror_idx].count = count;
+        }
+
+        /* update the dreq->count by finding the minimum agreed count from all
+         * mirrors */
+        count = dreq->mirrors[0].count;
+
+        for (i = 1; i < dreq->mirror_count; i++)
+                count = min(count, dreq->mirrors[i].count);
+
+        dreq->count = count;
+}
+
 /*
  * nfs_direct_select_verf - select the right verifier
  * @dreq - direct request possibly spanning multiple servers
  * @ds_clp - nfs_client of data server or NULL if MDS / non-pnfs
- * @ds_idx - index of data server in data server list, only valid if ds_clp set
+ * @commit_idx - commit bucket index for the DS
  *
  * returns the correct verifier to use given the role of the server
  */
 static struct nfs_writeverf *
 nfs_direct_select_verf(struct nfs_direct_req *dreq,
                        struct nfs_client *ds_clp,
-                       int ds_idx)
+                       int commit_idx)
 {
         struct nfs_writeverf *verfp = &dreq->verf;
 
 #ifdef CONFIG_NFS_V4_1
         if (ds_clp) {
                 /* pNFS is in use, use the DS verf */
-                if (ds_idx >= 0 && ds_idx < dreq->ds_cinfo.nbuckets)
-                        verfp = &dreq->ds_cinfo.buckets[ds_idx].direct_verf;
+                if (commit_idx >= 0 && commit_idx < dreq->ds_cinfo.nbuckets)
+                        verfp = &dreq->ds_cinfo.buckets[commit_idx].direct_verf;
                 else
                         WARN_ON_ONCE(1);
         }
@@ -148,8 +187,7 @@ static void nfs_direct_set_hdr_verf(struct nfs_direct_req *dreq,
 {
         struct nfs_writeverf *verfp;
 
-        verfp = nfs_direct_select_verf(dreq, hdr->ds_clp,
-                                      hdr->ds_idx);
+        verfp = nfs_direct_select_verf(dreq, hdr->ds_clp, hdr->ds_commit_idx);
         WARN_ON_ONCE(verfp->committed >= 0);
         memcpy(verfp, &hdr->verf, sizeof(struct nfs_writeverf));
         WARN_ON_ONCE(verfp->committed < 0);
@@ -169,8 +207,7 @@ static int nfs_direct_set_or_cmp_hdr_verf(struct nfs_direct_req *dreq,
 {
         struct nfs_writeverf *verfp;
 
-        verfp = nfs_direct_select_verf(dreq, hdr->ds_clp,
-                                         hdr->ds_idx);
+        verfp = nfs_direct_select_verf(dreq, hdr->ds_clp, hdr->ds_commit_idx);
         if (verfp->committed < 0) {
                 nfs_direct_set_hdr_verf(dreq, hdr);
                 return 0;
@@ -193,7 +230,11 @@ static int nfs_direct_cmp_commit_data_verf(struct nfs_direct_req *dreq,
 
         verfp = nfs_direct_select_verf(dreq, data->ds_clp,
                                          data->ds_commit_index);
-        WARN_ON_ONCE(verfp->committed < 0);
+
+        /* verifier not set so always fail */
+        if (verfp->committed < 0)
+                return 1;
+
         return memcmp(verfp, &data->verf, sizeof(struct nfs_writeverf));
 }
 
@@ -212,6 +253,12 @@ static int nfs_direct_cmp_commit_data_verf(struct nfs_direct_req *dreq,
  */
 ssize_t nfs_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter, loff_t pos)
 {
+        struct inode *inode = iocb->ki_filp->f_mapping->host;
+
+        /* we only support swap file calling nfs_direct_IO */
+        if (!IS_SWAPFILE(inode))
+                return 0;
+
 #ifndef CONFIG_NFS_SWAP
         dprintk("NFS: nfs_direct_IO (%pD) off/no(%Ld/%lu) EINVAL\n",
                         iocb->ki_filp, (long long) pos, iter->nr_segs);
@@ -243,6 +290,18 @@ void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
         cinfo->completion_ops = &nfs_direct_commit_completion_ops;
 }
 
+static inline void nfs_direct_setup_mirroring(struct nfs_direct_req *dreq,
+                                             struct nfs_pageio_descriptor *pgio,
+                                             struct nfs_page *req)
+{
+        int mirror_count = 1;
+
+        if (pgio->pg_ops->pg_get_mirror_count)
+                mirror_count = pgio->pg_ops->pg_get_mirror_count(pgio, req);
+
+        dreq->mirror_count = mirror_count;
+}
+
 static inline struct nfs_direct_req *nfs_direct_req_alloc(void)
 {
         struct nfs_direct_req *dreq;
@@ -257,6 +316,7 @@ static inline struct nfs_direct_req *nfs_direct_req_alloc(void)
         INIT_LIST_HEAD(&dreq->mds_cinfo.list);
         dreq->verf.committed = NFS_INVALID_STABLE_HOW;  /* not set yet */
         INIT_WORK(&dreq->work, nfs_direct_write_schedule_work);
+        dreq->mirror_count = 1;
         spin_lock_init(&dreq->lock);
 
         return dreq;
@@ -363,7 +423,8 @@ static void nfs_direct_read_completion(struct nfs_pgio_header *hdr)
         if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) && (hdr->good_bytes == 0))
                 dreq->error = hdr->error;
         else
-                dreq->count += hdr->good_bytes;
+                nfs_direct_good_bytes(dreq, hdr);
+
         spin_unlock(&dreq->lock);
 
         while (!list_empty(&hdr->pages)) {
@@ -541,6 +602,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter,
 
         dreq->inode = inode;
         dreq->bytes_left = count;
+        dreq->io_start = pos;
         dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp));
         l_ctx = nfs_get_lock_context(dreq->ctx);
         if (IS_ERR(l_ctx)) {
@@ -573,6 +635,20 @@ out:
         return result;
 }
 
+static void
+nfs_direct_write_scan_commit_list(struct inode *inode,
+                                  struct list_head *list,
+                                  struct nfs_commit_info *cinfo)
+{
+        spin_lock(cinfo->lock);
+#ifdef CONFIG_NFS_V4_1
+        if (cinfo->ds != NULL && cinfo->ds->nwritten != 0)
+                NFS_SERVER(inode)->pnfs_curr_ld->recover_commit_reqs(list, cinfo);
+#endif
+        nfs_scan_commit_list(&cinfo->mds->list, list, cinfo, 0);
+        spin_unlock(cinfo->lock);
+}
+
 static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
 {
         struct nfs_pageio_descriptor desc;
@@ -580,20 +656,23 @@ static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
         LIST_HEAD(reqs);
         struct nfs_commit_info cinfo;
         LIST_HEAD(failed);
+        int i;
 
         nfs_init_cinfo_from_dreq(&cinfo, dreq);
-        pnfs_recover_commit_reqs(dreq->inode, &reqs, &cinfo);
-        spin_lock(cinfo.lock);
-        nfs_scan_commit_list(&cinfo.mds->list, &reqs, &cinfo, 0);
-        spin_unlock(cinfo.lock);
+        nfs_direct_write_scan_commit_list(dreq->inode, &reqs, &cinfo);
 
         dreq->count = 0;
+        for (i = 0; i < dreq->mirror_count; i++)
+                dreq->mirrors[i].count = 0;
         get_dreq(dreq);
 
         nfs_pageio_init_write(&desc, dreq->inode, FLUSH_STABLE, false,
                               &nfs_direct_write_completion_ops);
         desc.pg_dreq = dreq;
 
+        req = nfs_list_entry(reqs.next);
+        nfs_direct_setup_mirroring(dreq, &desc, req);
+
         list_for_each_entry_safe(req, tmp, &reqs, wb_list) {
                 if (!nfs_pageio_add_request(&desc, req)) {
                         nfs_list_remove_request(req);
@@ -640,7 +719,7 @@ static void nfs_direct_commit_complete(struct nfs_commit_data *data)
                 nfs_list_remove_request(req);
                 if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES) {
                         /* Note the rewrite will go through mds */
-                        nfs_mark_request_commit(req, NULL, &cinfo);
+                        nfs_mark_request_commit(req, NULL, &cinfo, 0);
                 } else
                         nfs_release_request(req);
                 nfs_unlock_and_release_request(req);
@@ -715,7 +794,7 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr)
                 dreq->error = hdr->error;
         }
         if (dreq->error == 0) {
-                dreq->count += hdr->good_bytes;
+                nfs_direct_good_bytes(dreq, hdr);
                 if (nfs_write_need_commit(hdr)) {
                         if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES)
                                 request_commit = true;
@@ -739,7 +818,8 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr)
                 nfs_list_remove_request(req);
                 if (request_commit) {
                         kref_get(&req->wb_kref);
-                        nfs_mark_request_commit(req, hdr->lseg, &cinfo);
+                        nfs_mark_request_commit(req, hdr->lseg, &cinfo,
+                                hdr->ds_commit_idx);
                 }
                 nfs_unlock_and_release_request(req);
         }
@@ -820,6 +900,9 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
                                 result = PTR_ERR(req);
                                 break;
                         }
+
+                        nfs_direct_setup_mirroring(dreq, &desc, req);
+
                         nfs_lock_request(req);
                         req->wb_index = pos >> PAGE_SHIFT;
                         req->wb_offset = pos & ~PAGE_MASK;
@@ -928,6 +1011,7 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter,
 
         dreq->inode = inode;
         dreq->bytes_left = count;
+        dreq->io_start = pos;
         dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp));
         l_ctx = nfs_get_lock_context(dreq->ctx);
         if (IS_ERR(l_ctx)) {