GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

NFSv4.1/flexfiles: Allow coalescing of new layout segments and existing ones

Browse source 
In order to ensure atomicity of updates, we merge the old layout segments
into the new ones, and then invalidate the old ones.

Also ensure that we order the list of layout segments so that
RO segments are preferred over RW.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Trond Myklebust 2015-08-25 17:38:25 -04:00
parent 03772d2f00
commit 0762ed2ced
2 changed files with 76 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

60
fs/nfs/flexfilelayout/flexfilelayout.c
View file

@ -265,6 +265,65 @@ static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
}
}
static bool
ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
const struct pnfs_layout_range *l2)
{
u64 end1, end2;
if (l1->iomode != l2->iomode)
return l1->iomode != IOMODE_READ;
end1 = pnfs_calc_offset_end(l1->offset, l1->length);
end2 = pnfs_calc_offset_end(l2->offset, l2->length);
if (end1 < l2->offset)
return false;
if (end2 < l1->offset)
return true;
return l2->offset <= l1->offset;
}
static bool
ff_lseg_merge(struct pnfs_layout_segment *new,
struct pnfs_layout_segment *old)
{
u64 new_end, old_end;
if (new->pls_range.iomode != old->pls_range.iomode)
return false;
old_end = pnfs_calc_offset_end(old->pls_range.offset,
old->pls_range.length);
if (old_end < new->pls_range.offset)
return false;
new_end = pnfs_calc_offset_end(new->pls_range.offset,
new->pls_range.length);
if (new_end < old->pls_range.offset)
return false;
/* Mergeable: copy info from 'old' to 'new' */
if (new_end < old_end)
new_end = old_end;
if (new->pls_range.offset < old->pls_range.offset)
new->pls_range.offset = old->pls_range.offset;
new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
new_end);
if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
set_bit(NFS_LSEG_ROC, &new->pls_flags);
if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
set_bit(NFS_LSEG_LAYOUTRETURN, &new->pls_flags);
return true;
}
static void
ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
struct pnfs_layout_segment *lseg,
struct list_head *free_me)
{
pnfs_generic_layout_insert_lseg(lo, lseg,
ff_lseg_range_is_after,
ff_lseg_merge,
free_me);
}
static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
{
int i, j;
@ -2046,6 +2105,7 @@ static struct pnfs_layoutdriver_type flexfilelayout_type = {
.free_layout_hdr = ff_layout_free_layout_hdr,
.alloc_lseg = ff_layout_alloc_lseg,
.free_lseg = ff_layout_free_lseg,
.add_lseg = ff_layout_add_lseg,
.pg_read_ops = &ff_layout_pg_read_ops,
.pg_write_ops = &ff_layout_pg_write_ops,
.get_ds_info = ff_layout_get_ds_info,