From: Fred Isaman <iisaman@xxxxxxxxxx>
Prepare for filelayout_read_pagelist with helper functions that find the correct
data server, filehandle, and offset.
Signed-off-by: Andy Adamson <andros@xxxxxxxxxxxxxx>
Signed-off-by: Dean Hildebrand <dhildeb@xxxxxxxxxx>
Signed-off-by: Fred Isaman <iisaman@xxxxxxxxxx>
Signed-off-by: Marc Eshel <eshel@xxxxxxxxxxxxxxx>
Signed-off-by: Mike Sager <sager@xxxxxxxxxx>
Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx>
Signed-off-by: Tao Guo <guotao@xxxxxxxxxxxx>
Signed-off-by: Tigran Mkrtchyan <tigran@xxxxxxxxxxxxxx>
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@xxxxxxx>
Signed-off-by: Andy Adamson <andros@xxxxxxxxxx>
Signed-off-by: Benny Halevy <bhalevy@xxxxxxxxxxx>
---
fs/nfs/nfs4filelayout.c | 29 +++++++++++++++++++
fs/nfs/nfs4filelayout.h | 7 ++++
fs/nfs/nfs4filelayoutdev.c | 67 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 103 insertions(+), 0 deletions(-)
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 98e26e0..1c34809 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -66,6 +66,35 @@ filelayout_clear_layoutdriver(struct nfs_server *nfss)
return 0;
}
+/* This function is used by the layout driver to calculate the
+ * offset of the file on the dserver based on whether the
+ * layout type is STRIPE_DENSE or STRIPE_SPARSE
+ */
+static loff_t
+filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
+{
+ struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+
+ switch (flseg->stripe_type) {
+ case STRIPE_SPARSE:
+ return offset;
+
+ case STRIPE_DENSE:
+ {
+ u32 stripe_width;
+ u64 tmp, off;
+ u32 unit = flseg->stripe_unit;
+
+ stripe_width = unit * flseg->dsaddr->stripe_count;
+ tmp = off = offset - flseg->pattern_offset;
+ do_div(tmp, stripe_width);
+ return tmp * unit + do_div(off, unit);
+ }
+ }
+
+ BUG();
+}
+
/*
* filelayout_check_layout()
*
diff --git a/fs/nfs/nfs4filelayout.h b/fs/nfs/nfs4filelayout.h
index bbf60dd..9fef76e 100644
--- a/fs/nfs/nfs4filelayout.h
+++ b/fs/nfs/nfs4filelayout.h
@@ -83,9 +83,16 @@ FILELAYOUT_LSEG(struct pnfs_layout_segment *lseg)
generic_hdr);
}
+extern struct nfs_fh *
+nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j);
+
extern void nfs4_fl_free_deviceid_callback(struct pnfs_deviceid_node *);
extern void print_ds(struct nfs4_pnfs_ds *ds);
extern void print_deviceid(struct nfs4_deviceid *dev_id);
+u32 nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset);
+u32 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j);
+struct nfs4_pnfs_ds *nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg,
+ u32 ds_idx);
extern struct nfs4_file_layout_dsaddr *
nfs4_fl_find_get_deviceid(struct nfs_client *, struct nfs4_deviceid *dev_id);
struct nfs4_file_layout_dsaddr *
diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index 8e21e65..e8496f3 100644
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -512,3 +512,70 @@ nfs4_fl_find_get_deviceid(struct nfs_client *clp, struct nfs4_deviceid *id)
return (d == NULL) ? NULL :
container_of(d, struct nfs4_file_layout_dsaddr, deviceid);
}
+
+/*
+ * Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
+ * Then: ((res + fsi) % dsaddr->stripe_count)
+ */
+u32
+nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
+{
+ struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+ u64 tmp;
+
+ tmp = offset - flseg->pattern_offset;
+ do_div(tmp, flseg->stripe_unit);
+ tmp += flseg->first_stripe_index;
+ return do_div(tmp, flseg->dsaddr->stripe_count);
+}
+
+u32
+nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
+{
+ return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
+}
+
+struct nfs_fh *
+nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
+{
+ struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+ u32 i;
+
+ if (flseg->stripe_type == STRIPE_SPARSE) {
+ if (flseg->num_fh == 1)
+ i = 0;
+ else if (flseg->num_fh == 0)
+ /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
+ return NULL;
+ else
+ i = nfs4_fl_calc_ds_index(lseg, j);
+ } else
+ i = j;
+ return flseg->fh_array[i];
+}
+
+struct nfs4_pnfs_ds *
+nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
+{
+ struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
+ struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
+
+ if (ds == NULL) {
+ printk(KERN_ERR "%s: No data server for offset index %d\n",
+ __func__, ds_idx);
+ return NULL;
+ }
+
+ if (!ds->ds_clp) {
+ int err;
+
+ err = nfs4_ds_connect(NFS_SERVER(lseg->pls_layout->plh_inode),
+ dsaddr->ds_list[ds_idx]);
+ if (err) {
+ printk(KERN_ERR "%s nfs4_ds_connect error %d\n",
+ __func__, err);
+ return NULL;
+ }
+ }
+ return ds;
+}
--
1.7.2.3
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