kernel/fs/nfsd/blocklayoutxdr.c

   1 /*
   2  * Copyright (c) 2014 Christoph Hellwig.
   3  */
   4 #include <linux/sunrpc/svc.h>
   5 #include <linux/exportfs.h>
   6 #include <linux/nfs4.h>
   7
   8 #include "nfsd.h"
   9 #include "blocklayoutxdr.h"
  10
  11 #define NFSDDBG_FACILITY        NFSDDBG_PNFS
  12
  13
  14 __be32
  15 nfsd4_block_encode_layoutget(struct xdr_stream *xdr,
  16                 struct nfsd4_layoutget *lgp)
  17 {
  18         struct pnfs_block_extent *b = lgp->lg_content;
  19         int len = sizeof(__be32) + 5 * sizeof(__be64) + sizeof(__be32);
  20         __be32 *p;
  21
  22         p = xdr_reserve_space(xdr, sizeof(__be32) + len);
  23         if (!p)
  24                 return nfserr_toosmall;
  25
  26         *p++ = cpu_to_be32(len);
  27         *p++ = cpu_to_be32(1);          /* we always return a single extent */
  28
  29         p = xdr_encode_opaque_fixed(p, &b->vol_id,
  30                         sizeof(struct nfsd4_deviceid));
  31         p = xdr_encode_hyper(p, b->foff);
  32         p = xdr_encode_hyper(p, b->len);
  33         p = xdr_encode_hyper(p, b->soff);
  34         *p++ = cpu_to_be32(b->es);
  35         return 0;
  36 }
  37
  38 static int
  39 nfsd4_block_encode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
  40 {
  41         __be32 *p;
  42         int len;
  43
  44         switch (b->type) {
  45         case PNFS_BLOCK_VOLUME_SIMPLE:
  46                 len = 4 + 4 + 8 + 4 + b->simple.sig_len;
  47                 p = xdr_reserve_space(xdr, len);
  48                 if (!p)
  49                         return -ETOOSMALL;
  50
  51                 *p++ = cpu_to_be32(b->type);
  52                 *p++ = cpu_to_be32(1);  /* single signature */
  53                 p = xdr_encode_hyper(p, b->simple.offset);
  54                 p = xdr_encode_opaque(p, b->simple.sig, b->simple.sig_len);
  55                 break;
  56         default:
  57                 return -ENOTSUPP;
  58         }
  59
  60         return len;
  61 }
  62
  63 __be32
  64 nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
  65                 struct nfsd4_getdeviceinfo *gdp)
  66 {
  67         struct pnfs_block_deviceaddr *dev = gdp->gd_device;
  68         int len = sizeof(__be32), ret, i;
  69         __be32 *p;
  70
  71         p = xdr_reserve_space(xdr, len + sizeof(__be32));
  72         if (!p)
  73                 return nfserr_resource;
  74
  75         for (i = 0; i < dev->nr_volumes; i++) {
  76                 ret = nfsd4_block_encode_volume(xdr, &dev->volumes[i]);
  77                 if (ret < 0)
  78                         return nfserrno(ret);
  79                 len += ret;
  80         }
  81
  82         /*
  83          * Fill in the overall length and number of volumes at the beginning
  84          * of the layout.
  85          */
  86         *p++ = cpu_to_be32(len);
  87         *p++ = cpu_to_be32(dev->nr_volumes);
  88         return 0;
  89 }
  90
  91 int
  92 nfsd4_block_decode_layoutupdate(__be32 *p, u32 len, struct iomap **iomapp,
  93                 u32 block_size)
  94 {
  95         struct iomap *iomaps;
  96         u32 nr_iomaps, expected, i;
  97
  98         if (len < sizeof(u32)) {
  99                 dprintk("%s: extent array too small: %u\n", __func__, len);
 100                 return -EINVAL;
 101         }
 102
 103         nr_iomaps = be32_to_cpup(p++);
 104         expected = sizeof(__be32) + nr_iomaps * NFS4_BLOCK_EXTENT_SIZE;
 105         if (len != expected) {
 106                 dprintk("%s: extent array size mismatch: %u/%u\n",
 107                         __func__, len, expected);
 108                 return -EINVAL;
 109         }
 110
 111         iomaps = kcalloc(nr_iomaps, sizeof(*iomaps), GFP_KERNEL);
 112         if (!iomaps) {
 113                 dprintk("%s: failed to allocate extent array\n", __func__);
 114                 return -ENOMEM;
 115         }
 116
 117         for (i = 0; i < nr_iomaps; i++) {
 118                 struct pnfs_block_extent bex;
 119
 120                 memcpy(&bex.vol_id, p, sizeof(struct nfsd4_deviceid));
 121                 p += XDR_QUADLEN(sizeof(struct nfsd4_deviceid));
 122
 123                 p = xdr_decode_hyper(p, &bex.foff);
 124                 if (bex.foff & (block_size - 1)) {
 125                         dprintk("%s: unaligned offset 0x%llx\n",
 126                                 __func__, bex.foff);
 127                         goto fail;
 128                 }
 129                 p = xdr_decode_hyper(p, &bex.len);
 130                 if (bex.len & (block_size - 1)) {
 131                         dprintk("%s: unaligned length 0x%llx\n",
 132                                 __func__, bex.foff);
 133                         goto fail;
 134                 }
 135                 p = xdr_decode_hyper(p, &bex.soff);
 136                 if (bex.soff & (block_size - 1)) {
 137                         dprintk("%s: unaligned disk offset 0x%llx\n",
 138                                 __func__, bex.soff);
 139                         goto fail;
 140                 }
 141                 bex.es = be32_to_cpup(p++);
 142                 if (bex.es != PNFS_BLOCK_READWRITE_DATA) {
 143                         dprintk("%s: incorrect extent state %d\n",
 144                                 __func__, bex.es);
 145                         goto fail;
 146                 }
 147
 148                 iomaps[i].offset = bex.foff;
 149                 iomaps[i].length = bex.len;
 150         }
 151
 152         *iomapp = iomaps;
 153         return nr_iomaps;
 154 fail:
 155         kfree(iomaps);
 156         return -EINVAL;
 157 }