fs/nfsd/blocklayout.c

   1 /*
   2  * Copyright (c) 2014 Christoph Hellwig.
   3  */
   4 #include <linux/exportfs.h>
   5 #include <linux/genhd.h>
   6 #include <linux/slab.h>
   7
   8 #include <linux/nfsd/debug.h>
   9
  10 #include "blocklayoutxdr.h"
  11 #include "pnfs.h"
  12
  13 #define NFSDDBG_FACILITY        NFSDDBG_PNFS
  14
  15
  16 static __be32
  17 nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
  18                 struct nfsd4_layoutget *args)
  19 {
  20         struct nfsd4_layout_seg *seg = &args->lg_seg;
  21         struct super_block *sb = inode->i_sb;
  22         u32 block_size = (1 << inode->i_blkbits);
  23         struct pnfs_block_extent *bex;
  24         struct iomap iomap;
  25         u32 device_generation = 0;
  26         int error;
  27
  28         if (seg->offset & (block_size - 1)) {
  29                 dprintk("pnfsd: I/O misaligned\n");
  30                 goto out_layoutunavailable;
  31         }
  32
  33         /*
  34          * Some clients barf on non-zero block numbers for NONE or INVALID
  35          * layouts, so make sure to zero the whole structure.
  36          */
  37         error = -ENOMEM;
  38         bex = kzalloc(sizeof(*bex), GFP_KERNEL);
  39         if (!bex)
  40                 goto out_error;
  41         args->lg_content = bex;
  42
  43         error = sb->s_export_op->map_blocks(inode, seg->offset, seg->length,
  44                                             &iomap, seg->iomode != IOMODE_READ,
  45                                             &device_generation);
  46         if (error) {
  47                 if (error == -ENXIO)
  48                         goto out_layoutunavailable;
  49                 goto out_error;
  50         }
  51
  52         if (iomap.length < args->lg_minlength) {
  53                 dprintk("pnfsd: extent smaller than minlength\n");
  54                 goto out_layoutunavailable;
  55         }
  56
  57         switch (iomap.type) {
  58         case IOMAP_MAPPED:
  59                 if (seg->iomode == IOMODE_READ)
  60                         bex->es = PNFS_BLOCK_READ_DATA;
  61                 else
  62                         bex->es = PNFS_BLOCK_READWRITE_DATA;
  63                 bex->soff = (iomap.blkno << 9);
  64                 break;
  65         case IOMAP_UNWRITTEN:
  66                 if (seg->iomode & IOMODE_RW) {
  67                         /*
  68                          * Crack monkey special case from section 2.3.1.
  69                          */
  70                         if (args->lg_minlength == 0) {
  71                                 dprintk("pnfsd: no soup for you!\n");
  72                                 goto out_layoutunavailable;
  73                         }
  74
  75                         bex->es = PNFS_BLOCK_INVALID_DATA;
  76                         bex->soff = (iomap.blkno << 9);
  77                         break;
  78                 }
  79                 /*FALLTHRU*/
  80         case IOMAP_HOLE:
  81                 if (seg->iomode == IOMODE_READ) {
  82                         bex->es = PNFS_BLOCK_NONE_DATA;
  83                         break;
  84                 }
  85                 /*FALLTHRU*/
  86         case IOMAP_DELALLOC:
  87         default:
  88                 WARN(1, "pnfsd: filesystem returned %d extent\n", iomap.type);
  89                 goto out_layoutunavailable;
  90         }
  91
  92         error = nfsd4_set_deviceid(&bex->vol_id, fhp, device_generation);
  93         if (error)
  94                 goto out_error;
  95         bex->foff = iomap.offset;
  96         bex->len = iomap.length;
  97
  98         seg->offset = iomap.offset;
  99         seg->length = iomap.length;
 100
 101         dprintk("GET: 0x%llx:0x%llx %d\n", bex->foff, bex->len, bex->es);
 102         return 0;
 103
 104 out_error:
 105         seg->length = 0;
 106         return nfserrno(error);
 107 out_layoutunavailable:
 108         seg->length = 0;
 109         return nfserr_layoutunavailable;
 110 }
 111
 112 static __be32
 113 nfsd4_block_commit_blocks(struct inode *inode, struct nfsd4_layoutcommit *lcp,
 114                 struct iomap *iomaps, int nr_iomaps)
 115 {
 116         loff_t new_size = lcp->lc_last_wr + 1;
 117         struct iattr iattr = { .ia_valid = 0 };
 118         int error;
 119
 120         if (lcp->lc_mtime.tv_nsec == UTIME_NOW ||
 121             timespec_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
 122                 lcp->lc_mtime = current_fs_time(inode->i_sb);
 123         iattr.ia_valid |= ATTR_ATIME | ATTR_CTIME | ATTR_MTIME;
 124         iattr.ia_atime = iattr.ia_ctime = iattr.ia_mtime = lcp->lc_mtime;
 125
 126         if (new_size > i_size_read(inode)) {
 127                 iattr.ia_valid |= ATTR_SIZE;
 128                 iattr.ia_size = new_size;
 129         }
 130
 131         error = inode->i_sb->s_export_op->commit_blocks(inode, iomaps,
 132                         nr_iomaps, &iattr);
 133         kfree(iomaps);
 134         return nfserrno(error);
 135 }
 136
 137 #ifdef CONFIG_NFSD_BLOCKLAYOUT
 138 static int
 139 nfsd4_block_get_device_info_simple(struct super_block *sb,
 140                 struct nfsd4_getdeviceinfo *gdp)
 141 {
 142         struct pnfs_block_deviceaddr *dev;
 143         struct pnfs_block_volume *b;
 144
 145         dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
 146                       sizeof(struct pnfs_block_volume), GFP_KERNEL);
 147         if (!dev)
 148                 return -ENOMEM;
 149         gdp->gd_device = dev;
 150
 151         dev->nr_volumes = 1;
 152         b = &dev->volumes[0];
 153
 154         b->type = PNFS_BLOCK_VOLUME_SIMPLE;
 155         b->simple.sig_len = PNFS_BLOCK_UUID_LEN;
 156         return sb->s_export_op->get_uuid(sb, b->simple.sig, &b->simple.sig_len,
 157                         &b->simple.offset);
 158 }
 159
 160 static __be32
 161 nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
 162                 struct nfsd4_getdeviceinfo *gdp)
 163 {
 164         if (sb->s_bdev != sb->s_bdev->bd_contains)
 165                 return nfserr_inval;
 166         return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
 167 }
 168
 169 static __be32
 170 nfsd4_block_proc_layoutcommit(struct inode *inode,
 171                 struct nfsd4_layoutcommit *lcp)
 172 {
 173         struct iomap *iomaps;
 174         int nr_iomaps;
 175
 176         nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
 177                         lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
 178         if (nr_iomaps < 0)
 179                 return nfserrno(nr_iomaps);
 180
 181         return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
 182 }
 183
 184 const struct nfsd4_layout_ops bl_layout_ops = {
 185         /*
 186          * Pretend that we send notification to the client.  This is a blatant
 187          * lie to force recent Linux clients to cache our device IDs.
 188          * We rarely ever change the device ID, so the harm of leaking deviceids
 189          * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
 190          * in this regard, but I filed errata 4119 for this a while ago, and
 191          * hopefully the Linux client will eventually start caching deviceids
 192          * without this again.
 193          */
 194         .notify_types           =
 195                         NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
 196         .proc_getdeviceinfo     = nfsd4_block_proc_getdeviceinfo,
 197         .encode_getdeviceinfo   = nfsd4_block_encode_getdeviceinfo,
 198         .proc_layoutget         = nfsd4_block_proc_layoutget,
 199         .encode_layoutget       = nfsd4_block_encode_layoutget,
 200         .proc_layoutcommit      = nfsd4_block_proc_layoutcommit,
 201 };
 202 #endif /* CONFIG_NFSD_BLOCKLAYOUT */