nfs: Convert to separately allocated bdi

Allocate struct backing_dev_info separately instead of embedding it
inside the superblock. This unifies handling of bdi among users.

CC: Anna Schumaker <anna.schumaker@netapp.com>
CC: linux-nfs@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 390ada8741bcbfd2e4aaecb3f759ec0707003674..04d15a0045e37173c124f78771243f8b444f3dce 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -761,9 +761,6 @@ static void nfs_server_set_fsinfo(struct nfs_server *server,
                server->rsize = NFS_MAX_FILE_IO_SIZE;
        server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
 
-       server->backing_dev_info.name = "nfs";
-       server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
-
        if (server->wsize > max_rpc_payload)
                server->wsize = max_rpc_payload;
        if (server->wsize > NFS_MAX_FILE_IO_SIZE)
@@ -917,12 +914,6 @@ struct nfs_server *nfs_alloc_server(void)
                return NULL;
        }
 
-       if (bdi_init(&server->backing_dev_info)) {
-               nfs_free_iostats(server->io_stats);
-               kfree(server);
-               return NULL;
-       }
-
        ida_init(&server->openowner_id);
        ida_init(&server->lockowner_id);
        pnfs_init_server(server);
@@ -953,7 +944,6 @@ void nfs_free_server(struct nfs_server *server)
        ida_destroy(&server->lockowner_id);
        ida_destroy(&server->openowner_id);
        nfs_free_iostats(server->io_stats);
-       bdi_destroy(&server->backing_dev_info);
        kfree(server);
        nfs_release_automount_timer();
        dprintk("<-- nfs_free_server()\n");

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 7b38fedb7e032824ec509edca5cf465a22147851..9dc65d7ae7541902e4235abbc5a5cc8285fc7f30 100644 (file)
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -139,7 +139,7 @@ struct nfs_mount_request {
 };
 
 struct nfs_mount_info {
-       void (*fill_super)(struct super_block *, struct nfs_mount_info *);
+       int (*fill_super)(struct super_block *, struct nfs_mount_info *);
        int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
        struct nfs_parsed_mount_data *parsed;
        struct nfs_clone_mount *cloned;
@@ -407,7 +407,7 @@ struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *
 struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
                const char *, struct nfs_mount_info *);
 void nfs_kill_super(struct super_block *);
-void nfs_fill_super(struct super_block *, struct nfs_mount_info *);
+int nfs_fill_super(struct super_block *, struct nfs_mount_info *);
 
 extern struct rpc_stat nfs_rpcstat;
 
@@ -458,7 +458,7 @@ extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
 
 /* super.c */
-void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
+int nfs_clone_super(struct super_block *, struct nfs_mount_info *);
 void nfs_umount_begin(struct super_block *);
 int  nfs_statfs(struct dentry *, struct kstatfs *);
 int  nfs_show_options(struct seq_file *, struct dentry *);

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 54e0f9f2dd94903d2d6d96de46287ebc31fe1b6e..8d97aa70407e487b32400f7937db3a276d1edc2e 100644 (file)
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2315,18 +2315,17 @@ inline void nfs_initialise_sb(struct super_block *sb)
                sb->s_blocksize = nfs_block_bits(server->wsize,
                                                 &sb->s_blocksize_bits);
 
-       sb->s_bdi = &server->backing_dev_info;
-
        nfs_super_set_maxbytes(sb, server->maxfilesize);
 }
 
 /*
  * Finish setting up an NFS2/3 superblock
  */
-void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
+int nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
 {
        struct nfs_parsed_mount_data *data = mount_info->parsed;
        struct nfs_server *server = NFS_SB(sb);
+       int ret;
 
        sb->s_blocksize_bits = 0;
        sb->s_blocksize = 0;
@@ -2344,13 +2343,21 @@ void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
        }
 
        nfs_initialise_sb(sb);
+
+       ret = super_setup_bdi_name(sb, "%u:%u", MAJOR(server->s_dev),
+                                  MINOR(server->s_dev));
+       if (ret)
+               return ret;
+       sb->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
+       return 0;
+
 }
 EXPORT_SYMBOL_GPL(nfs_fill_super);
 
 /*
  * Finish setting up a cloned NFS2/3/4 superblock
  */
-void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
+int nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
 {
        const struct super_block *old_sb = mount_info->cloned->sb;
        struct nfs_server *server = NFS_SB(sb);
@@ -2370,6 +2377,11 @@ void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
        }
 
        nfs_initialise_sb(sb);
+
+       sb->s_bdi = bdi_get(old_sb->s_bdi);
+       sb->s_iflags |= SB_I_DYNBDI;
+
+       return 0;
 }
 
 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
@@ -2522,11 +2534,6 @@ static void nfs_get_cache_cookie(struct super_block *sb,
 }
 #endif
 
-static int nfs_bdi_register(struct nfs_server *server)
-{
-       return bdi_register_dev(&server->backing_dev_info, server->s_dev);
-}
-
 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
                        struct nfs_mount_info *mount_info)
 {
@@ -2594,17 +2601,14 @@ struct dentry *nfs_fs_mount_common(struct nfs_server *server,
                nfs_free_server(server);
                server = NULL;
        } else {
-               error = nfs_bdi_register(server);
-               if (error) {
-                       mntroot = ERR_PTR(error);
-                       goto error_splat_super;
-               }
                server->super = s;
        }
 
        if (!s->s_root) {
                /* initial superblock/root creation */
-               mount_info->fill_super(s, mount_info);
+               error = mount_info->fill_super(s, mount_info);
+               if (error)
+                       goto error_splat_super;
                nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
        }
 

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index abb2c8a3be42e4755f747c62a1cec5466f13ee77..cc341fc7fd44212d508022c87e9023ba291cfc7d 100644 (file)
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -263,16 +263,15 @@ int nfs_congestion_kb;
 
 static void nfs_set_page_writeback(struct page *page)
 {
-       struct nfs_server *nfss = NFS_SERVER(page_file_mapping(page)->host);
+       struct inode *inode = page_file_mapping(page)->host;
+       struct nfs_server *nfss = NFS_SERVER(inode);
        int ret = test_set_page_writeback(page);
 
        WARN_ON_ONCE(ret != 0);
 
        if (atomic_long_inc_return(&nfss->writeback) >
-                       NFS_CONGESTION_ON_THRESH) {
-               set_bdi_congested(&nfss->backing_dev_info,
-                                       BLK_RW_ASYNC);
-       }
+                       NFS_CONGESTION_ON_THRESH)
+               set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC);
 }
 
 static void nfs_end_page_writeback(struct nfs_page *req)
@@ -285,7 +284,7 @@ static void nfs_end_page_writeback(struct nfs_page *req)
 
        end_page_writeback(req->wb_page);
        if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)
-               clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC);
+               clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC);
 }
 
 
@@ -1808,7 +1807,7 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data)
        }
        nfss = NFS_SERVER(data->inode);
        if (atomic_long_read(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)
-               clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC);
+               clear_bdi_congested(inode_to_bdi(data->inode), BLK_RW_ASYNC);
 
        nfs_init_cinfo(&cinfo, data->inode, data->dreq);
        nfs_commit_end(cinfo.mds);

diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index b34097c6784864193e67053f8fa8e5bbbc092071..e1502c55741ef805eb2fcc2c2dadfc07d2b0d0dc 100644 (file)
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -133,7 +133,6 @@ struct nfs_server {
        struct rpc_clnt *       client_acl;     /* ACL RPC client handle */
        struct nlm_host         *nlm_host;      /* NLM client handle */
        struct nfs_iostats __percpu *io_stats;  /* I/O statistics */
-       struct backing_dev_info backing_dev_info;
        atomic_long_t           writeback;      /* number of writeback pages */
        int                     flags;          /* various flags */
        unsigned int            caps;           /* server capabilities */