NFS: create struct nfs_commit_info

It is COMMIT that is handled the most differently between
the paged and direct paths.  Create a structure that encapsulates
everything either path needs to know about the commit state.

We could use void to hide some of the layout driver stuff, but
Trond suggests pulling it out to ensure type checking, given the
huge changes being made, and the fact that it doesn't interfere
with other drivers.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 66 insertions, 53 deletions

diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index e40523f2fe26..fe2cb55ca6b1 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -347,9 +347,11 @@ static void filelayout_commit_count_stats(struct rpc_task *task, void *data)
 static void filelayout_commit_release(void *calldata)
 {
         struct nfs_commit_data *data = calldata;
+        struct nfs_commit_info cinfo;
 
         nfs_commit_release_pages(data);
-        if (atomic_dec_and_test(&NFS_I(data->inode)->commits_outstanding))
+        nfs_init_cinfo(&cinfo, data->inode, data->dreq);
+        if (atomic_dec_and_test(&cinfo.mds->rpcs_out))
                 nfs_commit_clear_lock(NFS_I(data->inode));
         put_lseg(data->lseg);
         nfs_commitdata_release(data);
@@ -695,17 +697,16 @@ filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 
 static int
 filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
+                             struct nfs_commit_info *cinfo,
                              gfp_t gfp_flags)
 {
         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
-        struct nfs4_filelayout *flo = FILELAYOUT_FROM_HDR(lseg->pls_layout);
-
-        struct nfs4_fl_commit_bucket *buckets;
+        struct pnfs_commit_bucket *buckets;
         int size;
 
         if (fl->commit_through_mds)
                 return 0;
-        if (flo->commit_info.nbuckets != 0) {
+        if (cinfo->ds->nbuckets != 0) {
                 /* This assumes there is only one IOMODE_RW lseg.  What
                  * we really want to do is have a layout_hdr level
                  * dictionary of <multipath_list4, fh> keys, each
@@ -718,25 +719,25 @@ filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
         size = (fl->stripe_type == STRIPE_SPARSE) ?
                 fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
 
-        buckets = kcalloc(size, sizeof(struct nfs4_fl_commit_bucket),
+        buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
                           gfp_flags);
         if (!buckets)
                 return -ENOMEM;
         else {
                 int i;
 
-                spin_lock(&lseg->pls_layout->plh_inode->i_lock);
-                if (flo->commit_info.nbuckets != 0)
+                spin_lock(cinfo->lock);
+                if (cinfo->ds->nbuckets != 0)
                         kfree(buckets);
                 else {
-                        flo->commit_info.buckets = buckets;
-                        flo->commit_info.nbuckets = size;
+                        cinfo->ds->buckets = buckets;
+                        cinfo->ds->nbuckets = size;
                         for (i = 0; i < size; i++) {
                                 INIT_LIST_HEAD(&buckets[i].written);
                                 INIT_LIST_HEAD(&buckets[i].committing);
                         }
                 }
-                spin_unlock(&lseg->pls_layout->plh_inode->i_lock);
+                spin_unlock(cinfo->lock);
                 return 0;
         }
 }
@@ -821,6 +822,7 @@ static void
 filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
                          struct nfs_page *req)
 {
+        struct nfs_commit_info cinfo;
         int status;
 
         BUG_ON(pgio->pg_lseg != NULL);
@@ -836,7 +838,8 @@ filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
         /* If no lseg, fall back to write through mds */
         if (pgio->pg_lseg == NULL)
                 goto out_mds;
-        status = filelayout_alloc_commit_info(pgio->pg_lseg, GFP_NOFS);
+        nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
+        status = filelayout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
         if (status < 0) {
                 put_lseg(pgio->pg_lseg);
                 pgio->pg_lseg = NULL;
@@ -871,40 +874,42 @@ static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
  * If this will make the bucket empty, it will need to put the lseg reference.
  */
 static void
-filelayout_clear_request_commit(struct nfs_page *req)
+filelayout_clear_request_commit(struct nfs_page *req,
+                                struct nfs_commit_info *cinfo)
 {
         struct pnfs_layout_segment *freeme = NULL;
-        struct inode *inode = req->wb_context->dentry->d_inode;
 
-        spin_lock(&inode->i_lock);
+        spin_lock(cinfo->lock);
         if (!test_and_clear_bit(PG_COMMIT_TO_DS, &req->wb_flags))
                 goto out;
+        cinfo->ds->nwritten--;
         if (list_is_singular(&req->wb_list)) {
-                struct nfs4_fl_commit_bucket *bucket;
+                struct pnfs_commit_bucket *bucket;
 
                 bucket = list_first_entry(&req->wb_list,
-                                          struct nfs4_fl_commit_bucket,
+                                          struct pnfs_commit_bucket,
                                           written);
                 freeme = bucket->wlseg;
                 bucket->wlseg = NULL;
         }
 out:
-        nfs_request_remove_commit_list(req);
-        spin_unlock(&inode->i_lock);
+        nfs_request_remove_commit_list(req, cinfo);
+        spin_unlock(cinfo->lock);
         put_lseg(freeme);
 }
 
 static struct list_head *
 filelayout_choose_commit_list(struct nfs_page *req,
-                              struct pnfs_layout_segment *lseg)
+                              struct pnfs_layout_segment *lseg,
+                              struct nfs_commit_info *cinfo)
 {
         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
         u32 i, j;
         struct list_head *list;
-        struct nfs4_fl_commit_bucket *buckets;
+        struct pnfs_commit_bucket *buckets;
 
         if (fl->commit_through_mds)
-                return &NFS_I(req->wb_context->dentry->d_inode)->commit_list;
+                return &cinfo->mds->list;
 
         /* Note that we are calling nfs4_fl_calc_j_index on each page
          * that ends up being committed to a data server.  An attractive
@@ -914,7 +919,7 @@ filelayout_choose_commit_list(struct nfs_page *req,
          */
         j = nfs4_fl_calc_j_index(lseg, req_offset(req));
         i = select_bucket_index(fl, j);
-        buckets = FILELAYOUT_FROM_HDR(lseg->pls_layout)->commit_info.buckets;
+        buckets = cinfo->ds->buckets;
         list = &buckets[i].written;
         if (list_empty(list)) {
                 /* Non-empty buckets hold a reference on the lseg.  That ref
@@ -926,17 +931,19 @@ filelayout_choose_commit_list(struct nfs_page *req,
                 buckets[i].wlseg = get_lseg(lseg);
         }
         set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
+        cinfo->ds->nwritten++;
         return list;
 }
 
 static void
 filelayout_mark_request_commit(struct nfs_page *req,
-                struct pnfs_layout_segment *lseg)
+                               struct pnfs_layout_segment *lseg,
+                               struct nfs_commit_info *cinfo)
 {
         struct list_head *list;
 
-        list = filelayout_choose_commit_list(req, lseg);
-        nfs_request_add_commit_list(req, list);
+        list = filelayout_choose_commit_list(req, lseg, cinfo);
+        nfs_request_add_commit_list(req, list, cinfo);
 }
 
 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
@@ -993,8 +1000,9 @@ static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
 }
 
 static int
-filelayout_scan_ds_commit_list(struct nfs4_fl_commit_bucket *bucket, int max,
-                spinlock_t *lock)
+filelayout_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
+                               struct nfs_commit_info *cinfo,
+                               int max)
 {
         struct list_head *src = &bucket->written;
         struct list_head *dst = &bucket->committing;
@@ -1004,9 +1012,9 @@ filelayout_scan_ds_commit_list(struct nfs4_fl_commit_bucket *bucket, int max,
         list_for_each_entry_safe(req, tmp, src, wb_list) {
                 if (!nfs_lock_request(req))
                         continue;
-                if (cond_resched_lock(lock))
+                if (cond_resched_lock(cinfo->lock))
                         list_safe_reset_next(req, tmp, wb_list);
-                nfs_request_remove_commit_list(req);
+                nfs_request_remove_commit_list(req, cinfo);
                 clear_bit(PG_COMMIT_TO_DS, &req->wb_flags);
                 nfs_list_add_request(req, dst);
                 ret++;
@@ -1014,6 +1022,8 @@ filelayout_scan_ds_commit_list(struct nfs4_fl_commit_bucket *bucket, int max,
                         break;
         }
         if (ret) {
+                cinfo->ds->nwritten -= ret;
+                cinfo->ds->ncommitting += ret;
                 bucket->clseg = bucket->wlseg;
                 if (list_empty(src))
                         bucket->wlseg = NULL;
@@ -1024,37 +1034,32 @@ filelayout_scan_ds_commit_list(struct nfs4_fl_commit_bucket *bucket, int max,
 }
 
 /* Move reqs from written to committing lists, returning count of number moved.
- * Note called with i_lock held.
+ * Note called with cinfo->lock held.
  */
-static int filelayout_scan_commit_lists(struct inode *inode, int max,
-                spinlock_t *lock)
+static int filelayout_scan_commit_lists(struct nfs_commit_info *cinfo,
+                                        int max)
 {
-        struct nfs4_fl_commit_info *fl_cinfo;
         int i, rv = 0, cnt;
 
-        fl_cinfo = &FILELAYOUT_FROM_HDR(NFS_I(inode)->layout)->commit_info;
-        if (fl_cinfo->nbuckets == 0)
-                goto out_done;
-        for (i = 0; i < fl_cinfo->nbuckets && max != 0; i++) {
-                cnt = filelayout_scan_ds_commit_list(&fl_cinfo->buckets[i],
-                                max, lock);
+        for (i = 0; i < cinfo->ds->nbuckets && max != 0; i++) {
+                cnt = filelayout_scan_ds_commit_list(&cinfo->ds->buckets[i],
+                                                     cinfo, max);
                 max -= cnt;
                 rv += cnt;
         }
-out_done:
         return rv;
 }
 
 static unsigned int
-alloc_ds_commits(struct inode *inode, struct list_head *list)
+alloc_ds_commits(struct nfs_commit_info *cinfo, struct list_head *list)
 {
-        struct nfs4_fl_commit_info *fl_cinfo;
-        struct nfs4_fl_commit_bucket *bucket;
+        struct pnfs_ds_commit_info *fl_cinfo;
+        struct pnfs_commit_bucket *bucket;
         struct nfs_commit_data *data;
         int i, j;
         unsigned int nreq = 0;
 
-        fl_cinfo = &FILELAYOUT_FROM_HDR(NFS_I(inode)->layout)->commit_info;
+        fl_cinfo = cinfo->ds;
         bucket = fl_cinfo->buckets;
         for (i = 0; i < fl_cinfo->nbuckets; i++, bucket++) {
                 if (list_empty(&bucket->committing))
@@ -1073,7 +1078,7 @@ alloc_ds_commits(struct inode *inode, struct list_head *list)
         for (j = i; j < fl_cinfo->nbuckets; j++, bucket++) {
                 if (list_empty(&bucket->committing))
                         continue;
-                nfs_retry_commit(&bucket->committing, bucket->clseg);
+                nfs_retry_commit(&bucket->committing, bucket->clseg, cinfo);
                 put_lseg(bucket->clseg);
                 bucket->clseg = NULL;
         }
@@ -1084,7 +1089,7 @@ alloc_ds_commits(struct inode *inode, struct list_head *list)
 /* This follows nfs_commit_list pretty closely */
 static int
 filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
-                           int how)
+                           int how, struct nfs_commit_info *cinfo)
 {
         struct nfs_commit_data *data, *tmp;
         LIST_HEAD(list);
@@ -1097,17 +1102,17 @@ filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
                         list_add(&data->pages, &list);
                         nreq++;
                 } else
-                        nfs_retry_commit(mds_pages, NULL);
+                        nfs_retry_commit(mds_pages, NULL, cinfo);
         }
 
-        nreq += alloc_ds_commits(inode, &list);
+        nreq += alloc_ds_commits(cinfo, &list);
 
         if (nreq == 0) {
                 nfs_commit_clear_lock(NFS_I(inode));
                 goto out;
         }
 
-        atomic_add(nreq, &NFS_I(inode)->commits_outstanding);
+        atomic_add(nreq, &cinfo->mds->rpcs_out);
 
         list_for_each_entry_safe(data, tmp, &list, pages) {
                 list_del_init(&data->pages);
@@ -1116,14 +1121,15 @@ filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
                         nfs_initiate_commit(NFS_CLIENT(inode), data,
                                             data->mds_ops, how);
                 } else {
-                        struct nfs4_fl_commit_info *fl_cinfo;
+                        struct pnfs_commit_bucket *buckets;
 
-                        fl_cinfo = &FILELAYOUT_FROM_HDR(data->lseg->pls_layout)->commit_info;
-                        nfs_init_commit(data, &fl_cinfo->buckets[data->ds_commit_index].committing, data->lseg);
+                        buckets = cinfo->ds->buckets;
+                        nfs_init_commit(data, &buckets[data->ds_commit_index].committing, data->lseg);
                         filelayout_initiate_commit(data, how);
                 }
         }
 out:
+        cinfo->ds->ncommitting = 0;
         return PNFS_ATTEMPTED;
 }
 
@@ -1148,6 +1154,12 @@ filelayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
         kfree(FILELAYOUT_FROM_HDR(lo));
 }
 
+static struct pnfs_ds_commit_info *
+filelayout_get_ds_info(struct inode *inode)
+{
+        return &FILELAYOUT_FROM_HDR(NFS_I(inode)->layout)->commit_info;
+}
+
 static struct pnfs_layoutdriver_type filelayout_type = {
         .id                     = LAYOUT_NFSV4_1_FILES,
         .name                   = "LAYOUT_NFSV4_1_FILES",
@@ -1158,6 +1170,7 @@ static struct pnfs_layoutdriver_type filelayout_type = {
         .free_lseg              = filelayout_free_lseg,
         .pg_read_ops            = &filelayout_pg_read_ops,
         .pg_write_ops           = &filelayout_pg_write_ops,
+        .get_ds_info            = &filelayout_get_ds_info,
         .mark_request_commit    = filelayout_mark_request_commit,
         .clear_request_commit   = filelayout_clear_request_commit,
         .scan_commit_lists      = filelayout_scan_commit_lists,