Hi Trond, On Tue, Nov 24, 2020 at 8:54 AM <trondmy@xxxxxxxxxx> wrote: > > From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> > > rpc_prepare_reply_pages() currently expects the 'hdrsize' argument to > contain the length of the data that we expect to want placed in the head > kvec plus a count of 1 word of padding that is placed after the page data. > This is very confusing when trying to read the code, and sometimes leads > to callers adding an arbitrary value of '1' just in order to satisfy the > requirement (whether or not the page data actually needs such padding). > > This patch aims to clarify the code by changing the 'hdrsize' argument > to remove that 1 word of padding. This means we need to subtract the > padding from all the existing callers. After applying this patch, xfstests generic/013 on NFS v4.2 gives me: umount.nfs4: /mnt/test: device is busy rm: cannot remove '/mnt/test/fsstress.161220.1/p0/d4/d8XXXXXXXXXXXXXXXXXXXXXXXXX': Directory not empty rm: cannot remove '/mnt/test/fsstress.161220.2/p3/d6XX': Directory not empty rm: cannot remove '/mnt/test/fsstress.161220.2/p5': Directory not empty rm: cannot remove '/mnt/test/fsstress.161220.2/p6/d4XXXXXXXXXX': Directory not empty rm: cannot remove '/mnt/test/fsstress.161220.2/pc/d2/d4XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/d13X': Directory not empty rm: cannot remove '/mnt/test/fsstress.161220.2/pe/d1/dcXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX': Directory not empty rm: cannot remove '/mnt/test/fsstress.161220.2/p11/d1': Directory not empty rm: cannot remove '/mnt/test/fsstress.161220.2/p9/d0XXXXXXXXXXXXXXXXX/d1XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/d17XXXXXXXXX/d19XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX': Directory not empty Thanks, Anna > > Fixes: 02ef04e432ba ("NFS: Account for XDR pad of buf->pages") > Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> > --- > fs/nfs/nfs2xdr.c | 19 ++++++++++--------- > fs/nfs/nfs3xdr.c | 29 ++++++++++++++++------------- > fs/nfs/nfs4xdr.c | 36 +++++++++++++++++++----------------- > net/sunrpc/clnt.c | 5 +---- > net/sunrpc/xdr.c | 3 --- > 5 files changed, 46 insertions(+), 46 deletions(-) > > diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c > index f6676af37d5d..7fba7711e6b3 100644 > --- a/fs/nfs/nfs2xdr.c > +++ b/fs/nfs/nfs2xdr.c > @@ -34,6 +34,7 @@ > * Declare the space requirements for NFS arguments and replies as > * number of 32bit-words > */ > +#define NFS_pagepad_sz (1) /* Page padding */ > #define NFS_fhandle_sz (8) > #define NFS_sattr_sz (8) > #define NFS_filename_sz (1+(NFS2_MAXNAMLEN>>2)) > @@ -56,11 +57,11 @@ > > #define NFS_attrstat_sz (1+NFS_fattr_sz) > #define NFS_diropres_sz (1+NFS_fhandle_sz+NFS_fattr_sz) > -#define NFS_readlinkres_sz (2+1) > -#define NFS_readres_sz (1+NFS_fattr_sz+1+1) > +#define NFS_readlinkres_sz (2+NFS_pagepad_sz) > +#define NFS_readres_sz (1+NFS_fattr_sz+1+NFS_pagepad_sz) > #define NFS_writeres_sz (NFS_attrstat_sz) > #define NFS_stat_sz (1) > -#define NFS_readdirres_sz (1+1) > +#define NFS_readdirres_sz (1+NFS_pagepad_sz) > #define NFS_statfsres_sz (1+NFS_info_sz) > > static int nfs_stat_to_errno(enum nfs_stat); > @@ -592,8 +593,8 @@ static void nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req, > const struct nfs_readlinkargs *args = data; > > encode_fhandle(xdr, args->fh); > - rpc_prepare_reply_pages(req, args->pages, args->pgbase, > - args->pglen, NFS_readlinkres_sz); > + rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->pglen, > + NFS_readlinkres_sz - NFS_pagepad_sz); > } > > /* > @@ -628,8 +629,8 @@ static void nfs2_xdr_enc_readargs(struct rpc_rqst *req, > const struct nfs_pgio_args *args = data; > > encode_readargs(xdr, args); > - rpc_prepare_reply_pages(req, args->pages, args->pgbase, > - args->count, NFS_readres_sz); > + rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->count, > + NFS_readres_sz - NFS_pagepad_sz); > req->rq_rcv_buf.flags |= XDRBUF_READ; > } > > @@ -786,8 +787,8 @@ static void nfs2_xdr_enc_readdirargs(struct rpc_rqst *req, > const struct nfs_readdirargs *args = data; > > encode_readdirargs(xdr, args); > - rpc_prepare_reply_pages(req, args->pages, 0, > - args->count, NFS_readdirres_sz); > + rpc_prepare_reply_pages(req, args->pages, 0, args->count, > + NFS_readdirres_sz - NFS_pagepad_sz); > } > > /* > diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c > index 69971f6c840d..ca10072644ff 100644 > --- a/fs/nfs/nfs3xdr.c > +++ b/fs/nfs/nfs3xdr.c > @@ -33,6 +33,7 @@ > * Declare the space requirements for NFS arguments and replies as > * number of 32bit-words > */ > +#define NFS3_pagepad_sz (1) /* Page padding */ > #define NFS3_fhandle_sz (1+16) > #define NFS3_fh_sz (NFS3_fhandle_sz) /* shorthand */ > #define NFS3_sattr_sz (15) > @@ -69,13 +70,13 @@ > #define NFS3_removeres_sz (NFS3_setattrres_sz) > #define NFS3_lookupres_sz (1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz)) > #define NFS3_accessres_sz (1+NFS3_post_op_attr_sz+1) > -#define NFS3_readlinkres_sz (1+NFS3_post_op_attr_sz+1+1) > -#define NFS3_readres_sz (1+NFS3_post_op_attr_sz+3+1) > +#define NFS3_readlinkres_sz (1+NFS3_post_op_attr_sz+1+NFS3_pagepad_sz) > +#define NFS3_readres_sz (1+NFS3_post_op_attr_sz+3+NFS3_pagepad_sz) > #define NFS3_writeres_sz (1+NFS3_wcc_data_sz+4) > #define NFS3_createres_sz (1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz) > #define NFS3_renameres_sz (1+(2 * NFS3_wcc_data_sz)) > #define NFS3_linkres_sz (1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz) > -#define NFS3_readdirres_sz (1+NFS3_post_op_attr_sz+2+1) > +#define NFS3_readdirres_sz (1+NFS3_post_op_attr_sz+2+NFS3_pagepad_sz) > #define NFS3_fsstatres_sz (1+NFS3_post_op_attr_sz+13) > #define NFS3_fsinfores_sz (1+NFS3_post_op_attr_sz+12) > #define NFS3_pathconfres_sz (1+NFS3_post_op_attr_sz+6) > @@ -85,7 +86,8 @@ > #define ACL3_setaclargs_sz (NFS3_fh_sz+1+ \ > XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)) > #define ACL3_getaclres_sz (1+NFS3_post_op_attr_sz+1+ \ > - XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+1) > + XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+\ > + NFS3_pagepad_sz) > #define ACL3_setaclres_sz (1+NFS3_post_op_attr_sz) > > static int nfs3_stat_to_errno(enum nfs_stat); > @@ -909,8 +911,8 @@ static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req, > const struct nfs3_readlinkargs *args = data; > > encode_nfs_fh3(xdr, args->fh); > - rpc_prepare_reply_pages(req, args->pages, args->pgbase, > - args->pglen, NFS3_readlinkres_sz); > + rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->pglen, > + NFS3_readlinkres_sz - NFS3_pagepad_sz); > } > > /* > @@ -939,7 +941,8 @@ static void nfs3_xdr_enc_read3args(struct rpc_rqst *req, > const void *data) > { > const struct nfs_pgio_args *args = data; > - unsigned int replen = args->replen ? args->replen : NFS3_readres_sz; > + unsigned int replen = args->replen ? args->replen : > + NFS3_readres_sz - NFS3_pagepad_sz; > > encode_read3args(xdr, args); > rpc_prepare_reply_pages(req, args->pages, args->pgbase, > @@ -1239,8 +1242,8 @@ static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req, > const struct nfs3_readdirargs *args = data; > > encode_readdir3args(xdr, args); > - rpc_prepare_reply_pages(req, args->pages, 0, > - args->count, NFS3_readdirres_sz); > + rpc_prepare_reply_pages(req, args->pages, 0, args->count, > + NFS3_readdirres_sz - NFS3_pagepad_sz); > } > > /* > @@ -1281,8 +1284,8 @@ static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req, > const struct nfs3_readdirargs *args = data; > > encode_readdirplus3args(xdr, args); > - rpc_prepare_reply_pages(req, args->pages, 0, > - args->count, NFS3_readdirres_sz); > + rpc_prepare_reply_pages(req, args->pages, 0, args->count, > + NFS3_readdirres_sz - NFS3_pagepad_sz); > } > > /* > @@ -1328,7 +1331,7 @@ static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req, > if (args->mask & (NFS_ACL | NFS_DFACL)) { > rpc_prepare_reply_pages(req, args->pages, 0, > NFSACL_MAXPAGES << PAGE_SHIFT, > - ACL3_getaclres_sz); > + ACL3_getaclres_sz - NFS3_pagepad_sz); > req->rq_rcv_buf.flags |= XDRBUF_SPARSE_PAGES; > } > } > @@ -1648,7 +1651,7 @@ static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr, > result->op_status = status; > if (status != NFS3_OK) > goto out_status; > - result->replen = 4 + ((xdr_stream_pos(xdr) - pos) >> 2); > + result->replen = 3 + ((xdr_stream_pos(xdr) - pos) >> 2); > error = decode_read3resok(xdr, result); > out: > return error; > diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c > index c16b93df1bc1..3899ef3047f4 100644 > --- a/fs/nfs/nfs4xdr.c > +++ b/fs/nfs/nfs4xdr.c > @@ -84,6 +84,7 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req, > /* lock,open owner id: > * we currently use size 2 (u64) out of (NFS4_OPAQUE_LIMIT >> 2) > */ > +#define pagepad_maxsz (1) > #define open_owner_id_maxsz (1 + 2 + 1 + 1 + 2) > #define lock_owner_id_maxsz (1 + 1 + 4) > #define decode_lockowner_maxsz (1 + XDR_QUADLEN(IDMAP_NAMESZ)) > @@ -215,14 +216,14 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req, > nfs4_fattr_bitmap_maxsz) > #define encode_read_maxsz (op_encode_hdr_maxsz + \ > encode_stateid_maxsz + 3) > -#define decode_read_maxsz (op_decode_hdr_maxsz + 2 + 1) > +#define decode_read_maxsz (op_decode_hdr_maxsz + 2 + pagepad_maxsz) > #define encode_readdir_maxsz (op_encode_hdr_maxsz + \ > 2 + encode_verifier_maxsz + 5 + \ > nfs4_label_maxsz) > #define decode_readdir_maxsz (op_decode_hdr_maxsz + \ > - decode_verifier_maxsz + 1) > + decode_verifier_maxsz + pagepad_maxsz) > #define encode_readlink_maxsz (op_encode_hdr_maxsz) > -#define decode_readlink_maxsz (op_decode_hdr_maxsz + 1 + 1) > +#define decode_readlink_maxsz (op_decode_hdr_maxsz + 1 + pagepad_maxsz) > #define encode_write_maxsz (op_encode_hdr_maxsz + \ > encode_stateid_maxsz + 4) > #define decode_write_maxsz (op_decode_hdr_maxsz + \ > @@ -284,14 +285,14 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req, > #define decode_delegreturn_maxsz (op_decode_hdr_maxsz) > #define encode_getacl_maxsz (encode_getattr_maxsz) > #define decode_getacl_maxsz (op_decode_hdr_maxsz + \ > - nfs4_fattr_bitmap_maxsz + 1 + 1) > + nfs4_fattr_bitmap_maxsz + 1 + pagepad_maxsz) > #define encode_setacl_maxsz (op_encode_hdr_maxsz + \ > encode_stateid_maxsz + 3) > #define decode_setacl_maxsz (decode_setattr_maxsz) > #define encode_fs_locations_maxsz \ > (encode_getattr_maxsz) > #define decode_fs_locations_maxsz \ > - (1) > + (pagepad_maxsz) > #define encode_secinfo_maxsz (op_encode_hdr_maxsz + nfs4_name_maxsz) > #define decode_secinfo_maxsz (op_decode_hdr_maxsz + 1 + ((NFS_MAX_SECFLAVORS * (16 + GSS_OID_MAX_LEN)) / 4)) > > @@ -393,12 +394,13 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req, > /* devaddr4 payload is read into page */ \ > 1 /* notification bitmap length */ + \ > 1 /* notification bitmap, word 0 */ + \ > - 1 /* possible XDR padding */) > + pagepad_maxsz /* possible XDR padding */) > #define encode_layoutget_maxsz (op_encode_hdr_maxsz + 10 + \ > encode_stateid_maxsz) > #define decode_layoutget_maxsz (op_decode_hdr_maxsz + 8 + \ > decode_stateid_maxsz + \ > - XDR_QUADLEN(PNFS_LAYOUT_MAXSIZE) + 1) > + XDR_QUADLEN(PNFS_LAYOUT_MAXSIZE) + \ > + pagepad_maxsz) > #define encode_layoutcommit_maxsz (op_encode_hdr_maxsz + \ > 2 /* offset */ + \ > 2 /* length */ + \ > @@ -2342,7 +2344,7 @@ static void nfs4_xdr_enc_open(struct rpc_rqst *req, struct xdr_stream *xdr, > encode_layoutget(xdr, args->lg_args, &hdr); > rpc_prepare_reply_pages(req, args->lg_args->layout.pages, 0, > args->lg_args->layout.pglen, > - hdr.replen); > + hdr.replen - pagepad_maxsz); > } > encode_nops(&hdr); > } > @@ -2388,7 +2390,7 @@ static void nfs4_xdr_enc_open_noattr(struct rpc_rqst *req, > encode_layoutget(xdr, args->lg_args, &hdr); > rpc_prepare_reply_pages(req, args->lg_args->layout.pages, 0, > args->lg_args->layout.pglen, > - hdr.replen); > + hdr.replen - pagepad_maxsz); > } > encode_nops(&hdr); > } > @@ -2499,7 +2501,7 @@ static void nfs4_xdr_enc_readlink(struct rpc_rqst *req, struct xdr_stream *xdr, > encode_readlink(xdr, args, req, &hdr); > > rpc_prepare_reply_pages(req, args->pages, args->pgbase, > - args->pglen, hdr.replen); > + args->pglen, hdr.replen - pagepad_maxsz); > encode_nops(&hdr); > } > > @@ -2520,7 +2522,7 @@ static void nfs4_xdr_enc_readdir(struct rpc_rqst *req, struct xdr_stream *xdr, > encode_readdir(xdr, args, req, &hdr); > > rpc_prepare_reply_pages(req, args->pages, args->pgbase, > - args->count, hdr.replen); > + args->count, hdr.replen - pagepad_maxsz); > encode_nops(&hdr); > } > > @@ -2541,7 +2543,7 @@ static void nfs4_xdr_enc_read(struct rpc_rqst *req, struct xdr_stream *xdr, > encode_read(xdr, args, &hdr); > > rpc_prepare_reply_pages(req, args->pages, args->pgbase, > - args->count, hdr.replen); > + args->count, hdr.replen - pagepad_maxsz); > req->rq_rcv_buf.flags |= XDRBUF_READ; > encode_nops(&hdr); > } > @@ -2588,7 +2590,7 @@ static void nfs4_xdr_enc_getacl(struct rpc_rqst *req, struct xdr_stream *xdr, > ARRAY_SIZE(nfs4_acl_bitmap), &hdr); > > rpc_prepare_reply_pages(req, args->acl_pages, 0, > - args->acl_len, replen + 1); > + args->acl_len, replen); > encode_nops(&hdr); > } > > @@ -2810,7 +2812,7 @@ static void nfs4_xdr_enc_fs_locations(struct rpc_rqst *req, > } > > rpc_prepare_reply_pages(req, (struct page **)&args->page, 0, > - PAGE_SIZE, replen + 1); > + PAGE_SIZE, replen); > encode_nops(&hdr); > } > > @@ -3014,14 +3016,14 @@ static void nfs4_xdr_enc_getdeviceinfo(struct rpc_rqst *req, > encode_compound_hdr(xdr, req, &hdr); > encode_sequence(xdr, &args->seq_args, &hdr); > > - replen = hdr.replen + op_decode_hdr_maxsz; > + replen = hdr.replen + op_decode_hdr_maxsz + 2; > > encode_getdeviceinfo(xdr, args, &hdr); > > /* set up reply kvec. device_addr4 opaque data is read into the > * pages */ > rpc_prepare_reply_pages(req, args->pdev->pages, args->pdev->pgbase, > - args->pdev->pglen, replen + 2 + 1); > + args->pdev->pglen, replen); > encode_nops(&hdr); > } > > @@ -3043,7 +3045,7 @@ static void nfs4_xdr_enc_layoutget(struct rpc_rqst *req, > encode_layoutget(xdr, args, &hdr); > > rpc_prepare_reply_pages(req, args->layout.pages, 0, > - args->layout.pglen, hdr.replen); > + args->layout.pglen, hdr.replen - pagepad_maxsz); > encode_nops(&hdr); > } > > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c > index 3259120462ed..612f0a641f4c 100644 > --- a/net/sunrpc/clnt.c > +++ b/net/sunrpc/clnt.c > @@ -1251,10 +1251,7 @@ void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages, > unsigned int base, unsigned int len, > unsigned int hdrsize) > { > - /* Subtract one to force an extra word of buffer space for the > - * payload's XDR pad to fall into the rcv_buf's tail iovec. > - */ > - hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign - 1; > + hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign; > > xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len); > trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf); > diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c > index 3ce0a5daa9eb..5a450055469f 100644 > --- a/net/sunrpc/xdr.c > +++ b/net/sunrpc/xdr.c > @@ -193,9 +193,6 @@ xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset, > > tail->iov_base = buf + offset; > tail->iov_len = buflen - offset; > - if ((xdr->page_len & 3) == 0) > - tail->iov_len -= sizeof(__be32); > - > xdr->buflen += len; > } > EXPORT_SYMBOL_GPL(xdr_inline_pages); > -- > 2.28.0 >