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| author | Boaz Harrosh <bharrosh@panasas.com> | 2011-09-28 12:04:23 +0300 |
|---|---|---|
| committer | Boaz Harrosh <bharrosh@panasas.com> | 2011-10-14 18:54:41 +0200 |
| commit | 3bd9856857339d7ee8c4ad50030583f1b9415c39 (patch) | |
| tree | fa5d950b9beffa2a10bc698d452ae50b8e195d5e /fs/exofs/exofs.h | |
| parent | bbf9a31bba8c985780fe94da059cc5813a7920f5 (diff) | |
| download | lwn-3bd9856857339d7ee8c4ad50030583f1b9415c39.tar.gz lwn-3bd9856857339d7ee8c4ad50030583f1b9415c39.zip | |
ore: Support for partial component table
Users like the objlayout-driver would like to only pass
a partial device table that covers the IO in question.
For example exofs divides the file into raid-group-sized
chunks and only serves group_width number of devices at
a time.
The partiality is communicated by setting
ore_componets->first_dev and the array covers all logical
devices from oc->first_dev upto (oc->first_dev + oc->numdevs)
The ore_comp_dev() API receives a logical device index
and returns the actual present device in the table.
An out-of-range dev_index will BUG.
Logical device index is the theoretical device index as if
all the devices of a file are present. .i.e:
total_devs = group_width * mirror_p1 * group_count
0 <= dev_index < total_devs
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Diffstat (limited to 'fs/exofs/exofs.h')
| -rw-r--r-- | fs/exofs/exofs.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h index 006fd6f33571..51f4b4c40f09 100644 --- a/fs/exofs/exofs.h +++ b/fs/exofs/exofs.h @@ -217,6 +217,7 @@ static inline void exofs_init_comps(struct ore_components *oc, one_comp->obj.id = oid; exofs_make_credential(one_comp->cred, &one_comp->obj); + oc->first_dev = 0; oc->numdevs = sbi->layout.group_width * sbi->layout.mirrors_p1 * sbi->layout.group_count; oc->single_comp = EC_SINGLE_COMP; |