Return-Path: Received: from mx2.netapp.com ([216.240.18.37]:30725 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756130Ab0JOGRk (ORCPT ); Fri, 15 Oct 2010 02:17:40 -0400 From: Fred Isaman To: linux-nfs@vger.kernel.org Cc: Trond Myklebust Subject: [PATCH 05/12] RFC: nfs: ask for layouttypes during v4 fsinfo call Date: Sun, 10 Oct 2010 11:22:46 -0400 Message-Id: <1286724173-8493-6-git-send-email-iisaman@netapp.com> In-Reply-To: <1286724173-8493-1-git-send-email-iisaman@netapp.com> References: <1286724173-8493-1-git-send-email-iisaman@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Content-Type: text/plain MIME-Version: 1.0 From: The pNFS Team This information will be used to determine which layout driver, if any, to use for subsequent IO on this filesystem. Each driver is assigned an integer id, with 0 reserved to indicate no driver. The server can in theory return multiple ids. However, our current client implementation only notes the first entry and ignores the rest. Signed-off-by: Andy Adamson Signed-off-by: Benny Halevy Signed-off-by: Fred Isaman --- fs/nfs/nfs4proc.c | 2 +- fs/nfs/nfs4xdr.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/nfs_xdr.h | 1 + 3 files changed, 59 insertions(+), 1 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index aee1bcc..c3b1d98 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -129,7 +129,7 @@ const u32 nfs4_fsinfo_bitmap[2] = { FATTR4_WORD0_MAXFILESIZE | FATTR4_WORD0_MAXREAD | FATTR4_WORD0_MAXWRITE | FATTR4_WORD0_LEASE_TIME, - 0 + FATTR4_WORD1_FS_LAYOUT_TYPES }; const u32 nfs4_fs_locations_bitmap[2] = { diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 3feace6..6e4d18d 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -3868,6 +3868,60 @@ xdr_error: return status; } +/* + * Decode potentially multiple layout types. Currently we only support + * one layout driver per file system. + */ +static int decode_first_pnfs_layout_type(struct xdr_stream *xdr, + uint32_t *layouttype) +{ + uint32_t *p; + int num; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(!p)) + goto out_overflow; + num = be32_to_cpup(p); + + /* pNFS is not supported by the underlying file system */ + if (num == 0) { + *layouttype = 0; + return 0; + } + if (num > 1) + printk(KERN_INFO "%s: Warning: Multiple pNFS layout drivers " + "per filesystem not supported\n", __func__); + + /* Decode and set first layout type, move xdr->p past unused types */ + p = xdr_inline_decode(xdr, num * 4); + if (unlikely(!p)) + goto out_overflow; + *layouttype = be32_to_cpup(p); + return 0; +out_overflow: + print_overflow_msg(__func__, xdr); + return -EIO; +} + +/* + * The type of file system exported. + * Note we must ensure that layouttype is set in any non-error case. + */ +static int decode_attr_pnfstype(struct xdr_stream *xdr, uint32_t *bitmap, + uint32_t *layouttype) +{ + int status = 0; + + dprintk("%s: bitmap is %x\n", __func__, bitmap[1]); + if (unlikely(bitmap[1] & (FATTR4_WORD1_FS_LAYOUT_TYPES - 1U))) + return -EIO; + if (bitmap[1] & FATTR4_WORD1_FS_LAYOUT_TYPES) { + status = decode_first_pnfs_layout_type(xdr, layouttype); + bitmap[1] &= ~FATTR4_WORD1_FS_LAYOUT_TYPES; + } else + *layouttype = 0; + return status; +} static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo) { @@ -3894,6 +3948,9 @@ static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo) if ((status = decode_attr_maxwrite(xdr, bitmap, &fsinfo->wtmax)) != 0) goto xdr_error; fsinfo->wtpref = fsinfo->wtmax; + status = decode_attr_pnfstype(xdr, bitmap, &fsinfo->layouttype); + if (status) + goto xdr_error; status = verify_attr_len(xdr, savep, attrlen); xdr_error: diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index 5772b2c..d89920c 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -113,6 +113,7 @@ struct nfs_fsinfo { __u32 dtpref; /* pref. readdir transfer size */ __u64 maxfilesize; __u32 lease_time; /* in seconds */ + __u32 layouttype; /* supported pnfs layout driver */ }; struct nfs_fsstat { -- 1.7.2.1