Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / nfsd / blocklayout.c
diff --git a/kernel/fs/nfsd/blocklayout.c b/kernel/fs/nfsd/blocklayout.c
new file mode 100644 (file)
index 0000000..cdefaa3
--- /dev/null
@@ -0,0 +1,200 @@
+/*
+ * Copyright (c) 2014 Christoph Hellwig.
+ */
+#include <linux/exportfs.h>
+#include <linux/genhd.h>
+#include <linux/slab.h>
+
+#include <linux/nfsd/debug.h>
+
+#include "blocklayoutxdr.h"
+#include "pnfs.h"
+
+#define NFSDDBG_FACILITY       NFSDDBG_PNFS
+
+
+static int
+nfsd4_block_get_device_info_simple(struct super_block *sb,
+               struct nfsd4_getdeviceinfo *gdp)
+{
+       struct pnfs_block_deviceaddr *dev;
+       struct pnfs_block_volume *b;
+
+       dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
+                     sizeof(struct pnfs_block_volume), GFP_KERNEL);
+       if (!dev)
+               return -ENOMEM;
+       gdp->gd_device = dev;
+
+       dev->nr_volumes = 1;
+       b = &dev->volumes[0];
+
+       b->type = PNFS_BLOCK_VOLUME_SIMPLE;
+       b->simple.sig_len = PNFS_BLOCK_UUID_LEN;
+       return sb->s_export_op->get_uuid(sb, b->simple.sig, &b->simple.sig_len,
+                       &b->simple.offset);
+}
+
+static __be32
+nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
+               struct nfsd4_getdeviceinfo *gdp)
+{
+       if (sb->s_bdev != sb->s_bdev->bd_contains)
+               return nfserr_inval;
+       return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
+}
+
+static __be32
+nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
+               struct nfsd4_layoutget *args)
+{
+       struct nfsd4_layout_seg *seg = &args->lg_seg;
+       struct super_block *sb = inode->i_sb;
+       u32 block_size = (1 << inode->i_blkbits);
+       struct pnfs_block_extent *bex;
+       struct iomap iomap;
+       u32 device_generation = 0;
+       int error;
+
+       /*
+        * We do not attempt to support I/O smaller than the fs block size,
+        * or not aligned to it.
+        */
+       if (args->lg_minlength < block_size) {
+               dprintk("pnfsd: I/O too small\n");
+               goto out_layoutunavailable;
+       }
+       if (seg->offset & (block_size - 1)) {
+               dprintk("pnfsd: I/O misaligned\n");
+               goto out_layoutunavailable;
+       }
+
+       /*
+        * Some clients barf on non-zero block numbers for NONE or INVALID
+        * layouts, so make sure to zero the whole structure.
+        */
+       error = -ENOMEM;
+       bex = kzalloc(sizeof(*bex), GFP_KERNEL);
+       if (!bex)
+               goto out_error;
+       args->lg_content = bex;
+
+       error = sb->s_export_op->map_blocks(inode, seg->offset, seg->length,
+                                           &iomap, seg->iomode != IOMODE_READ,
+                                           &device_generation);
+       if (error) {
+               if (error == -ENXIO)
+                       goto out_layoutunavailable;
+               goto out_error;
+       }
+
+       if (iomap.length < args->lg_minlength) {
+               dprintk("pnfsd: extent smaller than minlength\n");
+               goto out_layoutunavailable;
+       }
+
+       switch (iomap.type) {
+       case IOMAP_MAPPED:
+               if (seg->iomode == IOMODE_READ)
+                       bex->es = PNFS_BLOCK_READ_DATA;
+               else
+                       bex->es = PNFS_BLOCK_READWRITE_DATA;
+               bex->soff = (iomap.blkno << 9);
+               break;
+       case IOMAP_UNWRITTEN:
+               if (seg->iomode & IOMODE_RW) {
+                       /*
+                        * Crack monkey special case from section 2.3.1.
+                        */
+                       if (args->lg_minlength == 0) {
+                               dprintk("pnfsd: no soup for you!\n");
+                               goto out_layoutunavailable;
+                       }
+
+                       bex->es = PNFS_BLOCK_INVALID_DATA;
+                       bex->soff = (iomap.blkno << 9);
+                       break;
+               }
+               /*FALLTHRU*/
+       case IOMAP_HOLE:
+               if (seg->iomode == IOMODE_READ) {
+                       bex->es = PNFS_BLOCK_NONE_DATA;
+                       break;
+               }
+               /*FALLTHRU*/
+       case IOMAP_DELALLOC:
+       default:
+               WARN(1, "pnfsd: filesystem returned %d extent\n", iomap.type);
+               goto out_layoutunavailable;
+       }
+
+       error = nfsd4_set_deviceid(&bex->vol_id, fhp, device_generation);
+       if (error)
+               goto out_error;
+       bex->foff = iomap.offset;
+       bex->len = iomap.length;
+
+       seg->offset = iomap.offset;
+       seg->length = iomap.length;
+
+       dprintk("GET: 0x%llx:0x%llx %d\n", bex->foff, bex->len, bex->es);
+       return 0;
+
+out_error:
+       seg->length = 0;
+       return nfserrno(error);
+out_layoutunavailable:
+       seg->length = 0;
+       return nfserr_layoutunavailable;
+}
+
+static __be32
+nfsd4_block_proc_layoutcommit(struct inode *inode,
+               struct nfsd4_layoutcommit *lcp)
+{
+       loff_t new_size = lcp->lc_last_wr + 1;
+       struct iattr iattr = { .ia_valid = 0 };
+       struct iomap *iomaps;
+       int nr_iomaps;
+       int error;
+
+       nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
+                       lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
+       if (nr_iomaps < 0)
+               return nfserrno(nr_iomaps);
+
+       if (lcp->lc_mtime.tv_nsec == UTIME_NOW ||
+           timespec_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
+               lcp->lc_mtime = current_fs_time(inode->i_sb);
+       iattr.ia_valid |= ATTR_ATIME | ATTR_CTIME | ATTR_MTIME;
+       iattr.ia_atime = iattr.ia_ctime = iattr.ia_mtime = lcp->lc_mtime;
+
+       if (new_size > i_size_read(inode)) {
+               iattr.ia_valid |= ATTR_SIZE;
+               iattr.ia_size = new_size;
+       }
+
+       error = inode->i_sb->s_export_op->commit_blocks(inode, iomaps,
+                       nr_iomaps, &iattr);
+       kfree(iomaps);
+       return nfserrno(error);
+}
+
+const struct nfsd4_layout_ops bl_layout_ops = {
+       /*
+        * Pretend that we send notification to the client.  This is a blatant
+        * lie to force recent Linux clients to cache our device IDs.
+        * We rarely ever change the device ID, so the harm of leaking deviceids
+        * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
+        * in this regard, but I filed errata 4119 for this a while ago, and
+        * hopefully the Linux client will eventually start caching deviceids
+        * without this again.
+        */
+       .notify_types           =
+                       NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
+       .proc_getdeviceinfo     = nfsd4_block_proc_getdeviceinfo,
+       .encode_getdeviceinfo   = nfsd4_block_encode_getdeviceinfo,
+       .proc_layoutget         = nfsd4_block_proc_layoutget,
+       .encode_layoutget       = nfsd4_block_encode_layoutget,
+       .proc_layoutcommit      = nfsd4_block_proc_layoutcommit,
+};