Note: When upper layer's read/write request cannot be fulfilled, the block
layout driver shouldn't silently mark the page as error. It should do
what can be done and  leave the rest to the upper layer. To do so, we
should set rdata/wdata->res.count properly.

When upper layer re-send the read/write request to finish the rest
part of the request, pgbase is the position where we should start at.

[pnfsblock: bl_write_pagelist support functions]
[pnfsblock: bl_write_pagelist adjust for missing PG_USE_PNFS]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfsblock: handle errors when read or write pagelist.]
Signed-off-by: NZhang Jingwang <yyalone@gmail.com>
[pnfs-block: use new write_pagelist api]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NJim Rees <rees@umich.edu>

[SQUASHME: pnfsblock: mds_offset is set in the generic layer]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>

[pnfsblock: mark IO error with NFS_LAYOUT_{RW|RO}_FAILED]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
[pnfsblock: SQUASHME: adjust to API change]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfsblock: fixup blksize alignment in bl_setup_layoutcommit]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
[pnfsblock: bl_write_pagelist adjust for missing PG_USE_PNFS]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfsblock: handle errors when read or write pagelist.]
Signed-off-by: NZhang Jingwang <yyalone@gmail.com>
[pnfs-block: use new write_pagelist api]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Note: When upper layer's read/write request cannot be fulfilled, the block
layout driver shouldn't silently mark the page as error. It should do
what can be done and  leave the rest to the upper layer. To do so, we
should set rdata/wdata->res.count properly.

When upper layer re-send the read/write request to finish the rest
part of the request, pgbase is the position where we should start at.

[pnfsblock: mark IO error with NFS_LAYOUT_{RW|RO}_FAILED]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
[pnfsblock: read path error handling]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfsblock: handle errors when read or write pagelist.]
Signed-off-by: NZhang Jingwang <yyalone@gmail.com>
[pnfs-block: use new read_pagelist api]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In blocklayout driver. There are two things happening
while layoutcommit/cleanup.
1. the modified extents are encoded.
2. On cleanup the extents are put back on the layout rw
   extents list, for reads.

In the new system where actual xdr encoding is done in
encode_layoutcommit() directly into xdr buffer, these are
the new commit stages:

1. On setup_layoutcommit, the range is adjusted as before
   and a structure is allocated for communication with
   bl_encode_layoutcommit && bl_cleanup_layoutcommit
   (Generic layer provides a void-star to hang it on)

2. bl_encode_layoutcommit is called to do the actual
   encoding directly into xdr. The commit-extent-list is not
   freed and is stored on above structure.
   FIXME: The code is not yet converted to the new XDR cleanup

3. On cleanup the commit-extent-list is put back by a call
   to set_to_rw() as before, but with no need for XDR decoding
   of the list as before. And the commit-extent-list is freed.
   Finally allocated structure is freed.

[rm inode and pnfs_layout_hdr args from cleanup_layoutcommit()]
Signed-off-by: NJim Rees <rees@umich.edu>
[pnfsblock: introduce bl_committing list]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
[pnfsblock: SQUASHME: adjust to API change]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[blocklayout: encode_layoutcommit implementation]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
[pnfsblock: fix bug setting up layoutcommit.]
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
[pnfsblock: cleanup_layoutcommit wants a status parameter]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In blocklayout driver. There are two things happening
while layoutcommit/cleanup.
1. the modified extents are encoded.
2. On cleanup the extents are put back on the layout rw
   extents list, for reads.

In the new system where actual xdr encoding is done in
encode_layoutcommit() directly into xdr buffer, these are
the new commit stages:

1. On setup_layoutcommit, the range is adjusted as before
   and a structure is allocated for communication with
   bl_encode_layoutcommit && bl_cleanup_layoutcommit
   (Generic layer provides a void-star to hang it on)

2. bl_encode_layoutcommit is called to do the actual
   encoding directly into xdr. The commit-extent-list is not
   freed and is stored on above structure.
   FIXME: The code is not yet converted to the new XDR cleanup

3. On cleanup the commit-extent-list is put back by a call
   to set_to_rw() as before, but with no need for XDR decoding
   of the list as before. And the commit-extent-list is freed.
   Finally allocated structure is freed.

[rm inode and pnfs_layout_hdr args from cleanup_layoutcommit()]
[pnfsblock: get rid of deprecated xdr macros]
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[blocklayout: encode_layoutcommit implementation]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
[pnfsblock: fix bug setting up layoutcommit.]
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
[pnfsblock: prevent commit list corruption]
[pnfsblock: fix layoutcommit with an empty opaque]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Adds working implementations of various support functions
to handle INVAL extents, needed by writes, such as
bl_mark_sectors_init and bl_is_sector_init.

[pnfsblock: fix 64-bit compiler warnings for extent manipulation]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
[Implement release_inval_marks]
Signed-off-by: NZhang Jingwang <zhangjingwang@nrchpc.ac.cn>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Call GETDEVICELIST during mount, then call and parse GETDEVICEINFO
for each device returned.

[pnfsblock: get rid of deprecated xdr macros]
Signed-off-by: NJim Rees <rees@umich.edu>
[pnfsblock: fix pnfs_deviceid references]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfsblock: fix print format warnings for sector_t and size_t]
[pnfs-block: #include <linux/vmalloc.h>]
[pnfsblock: no PNFS_NFS_SERVER]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[pnfsblock: fix bug determining size of striped volume]
[pnfsblock: fix oops when using multiple devices]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
[pnfsblock: get rid of vmap and deviceid->area structure]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfsblock: fix bug getting pnfs_layout_type in translate_devid().]
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NZhang Jingwang <Jingwang.Zhang@emc.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
[upcall bugfixes]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Adds structures and basic create/delete code for extents.
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NZhang Jingwang <Jingwang.Zhang@emc.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

[pnfsblock: use pnfs_generic_pg_init_read/write]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Define a configuration variable to enable/disable compilation of the
block driver code.

Add the minimal structure for a pnfs block layout driver, and empty
list-heads that will hold the extent data

[pnfsblock: make NFS_V4_1 select PNFS_BLOCK]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[pnfs-block: fix CONFIG_PNFS_BLOCK dependencies]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
[pnfsblock: SQUASHME: adjust to API change]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfs: move pnfs_layout_type inline in nfs_inode]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[blocklayout: encode_layoutcommit implementation]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
[pnfsblock: layout alloc and free]
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
[pnfs: move pnfs_layout_type inline in nfs_inode]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
[pnfsblock: define module alias]
Signed-off-by: NPeng Tao <peng_tao@emc.com>
[rm inode and pnfs_layout_hdr args from cleanup_layoutcommit()]
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>