NFSv4.1: Fix a few issues in filelayout_commit_pagelist

- Fix a race in which NFS_I(inode)->commits_outstanding could potentially
  go to zero (triggering a call to nfs_commit_clear_lock()) before we're
  done sending out all the commit RPC calls.

- If nfs_commitdata_alloc fails, there is no reason why we shouldn't
  try to send off all the commits-to-ds.

- Simplify the error handling.

- Change pnfs_commit_list() to always return either
  PNFS_ATTEMPTED or PNFS_NOT_ATTEMPTED.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
This commit is contained in:
Trond Myklebust 2012-03-16 13:52:45 -04:00
parent 8dd3775889
commit 9390f42546

View File

@ -980,12 +980,14 @@ out_done:
return rv;
}
static int alloc_ds_commits(struct inode *inode, struct list_head *list)
static unsigned int
alloc_ds_commits(struct inode *inode, struct list_head *list)
{
struct pnfs_layout_segment *lseg;
struct nfs4_filelayout_segment *fl;
struct nfs_write_data *data;
int i, j;
unsigned int nreq = 0;
/* Won't need this when non-whole file layout segments are supported
* instead we will use a pnfs_layout_hdr structure */
@ -998,15 +1000,14 @@ static int alloc_ds_commits(struct inode *inode, struct list_head *list)
continue;
data = nfs_commitdata_alloc();
if (!data)
goto out_bad;
break;
data->ds_commit_index = i;
data->lseg = lseg;
list_add(&data->pages, list);
nreq++;
}
put_lseg(lseg);
return 0;
out_bad:
/* Clean up on error */
for (j = i; j < fl->number_of_buckets; j++) {
if (list_empty(&fl->commit_buckets[i].committing))
continue;
@ -1015,7 +1016,7 @@ out_bad:
}
put_lseg(lseg);
/* Caller will clean up entries put on list */
return -ENOMEM;
return nreq;
}
/* This follows nfs_commit_list pretty closely */
@ -1025,21 +1026,29 @@ filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
{
struct nfs_write_data *data, *tmp;
LIST_HEAD(list);
unsigned int nreq = 0;
if (!list_empty(mds_pages)) {
data = nfs_commitdata_alloc();
if (!data)
goto out_bad;
data->lseg = NULL;
list_add(&data->pages, &list);
if (data != NULL) {
data->lseg = NULL;
list_add(&data->pages, &list);
nreq++;
} else
nfs_retry_commit(mds_pages, NULL);
}
if (alloc_ds_commits(inode, &list))
goto out_bad;
nreq += alloc_ds_commits(inode, &list);
if (nreq == 0) {
nfs_commit_clear_lock(NFS_I(inode));
goto out;
}
atomic_add(nreq, &NFS_I(inode)->commits_outstanding);
list_for_each_entry_safe(data, tmp, &list, pages) {
list_del_init(&data->pages);
atomic_inc(&NFS_I(inode)->commits_outstanding);
if (!data->lseg) {
nfs_init_commit(data, mds_pages, NULL);
nfs_initiate_commit(data, NFS_CLIENT(inode),
@ -1049,16 +1058,8 @@ filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
filelayout_initiate_commit(data, how);
}
}
return 0;
out_bad:
list_for_each_entry_safe(data, tmp, &list, pages) {
nfs_retry_commit(&data->pages, data->lseg);
list_del_init(&data->pages);
nfs_commit_free(data);
}
nfs_retry_commit(mds_pages, NULL);
nfs_commit_clear_lock(NFS_I(inode));
return -ENOMEM;
out:
return PNFS_ATTEMPTED;
}
static void