remarkable-linux/fs/nfs/objlayout/objio_osd.c
Boaz Harrosh 7de6e28417 pnfs-obj: Better IO pattern in case of unaligned offset
Depending on layout and ARCH, ORE has some limits on max IO sizes
which is communicated on (what else) ore_layout->max_io_length,
which is always stripe aligned.
This was considered as the pg_test boundary for splitting and starting
a new IO.

But in the case of a long IO where the start offset is not aligned
what would happen is that both end of IO[N] and start of IO[N+1]
would be unaligned, causing each IO boundary parity unit to be
calculated and written twice.

So what we do in this patch is split the very start of an unaligned
IO, up to a stripe boundary, and then next IO's can continue fully
aligned til the end.

We might be sacrificing the case where the full unaligned IO would
fit within a single max_io_length, but the sacrifice is well worth
the elimination of double calculation and parity units IO.
Actually the sacrificing is marginal and is almost unmeasurable.

TODO:
	If we know the total expected linear segment that will
	be received, at pg_init, we could use that information
	in many places:
	1. blocks-layout get_layout write segment size
	2. Better mds-threshold
	3. In above situation for a better clean split

	I will do this in future submission.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-08-02 17:42:51 -04:00

691 lines
18 KiB
C

/*
* pNFS Objects layout implementation over open-osd initiator library
*
* Copyright (C) 2009 Panasas Inc. [year of first publication]
* All rights reserved.
*
* Benny Halevy <bhalevy@panasas.com>
* Boaz Harrosh <bharrosh@panasas.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* See the file COPYING included with this distribution for more details.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Panasas company nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <linux/module.h>
#include <scsi/osd_ore.h>
#include "objlayout.h"
#define NFSDBG_FACILITY NFSDBG_PNFS_LD
struct objio_dev_ent {
struct nfs4_deviceid_node id_node;
struct ore_dev od;
};
static void
objio_free_deviceid_node(struct nfs4_deviceid_node *d)
{
struct objio_dev_ent *de = container_of(d, struct objio_dev_ent, id_node);
dprintk("%s: free od=%p\n", __func__, de->od.od);
osduld_put_device(de->od.od);
kfree(de);
}
static struct objio_dev_ent *_dev_list_find(const struct nfs_server *nfss,
const struct nfs4_deviceid *d_id)
{
struct nfs4_deviceid_node *d;
struct objio_dev_ent *de;
d = nfs4_find_get_deviceid(nfss->pnfs_curr_ld, nfss->nfs_client, d_id);
if (!d)
return NULL;
de = container_of(d, struct objio_dev_ent, id_node);
return de;
}
static struct objio_dev_ent *
_dev_list_add(const struct nfs_server *nfss,
const struct nfs4_deviceid *d_id, struct osd_dev *od,
gfp_t gfp_flags)
{
struct nfs4_deviceid_node *d;
struct objio_dev_ent *de = kzalloc(sizeof(*de), gfp_flags);
struct objio_dev_ent *n;
if (!de) {
dprintk("%s: -ENOMEM od=%p\n", __func__, od);
return NULL;
}
dprintk("%s: Adding od=%p\n", __func__, od);
nfs4_init_deviceid_node(&de->id_node,
nfss->pnfs_curr_ld,
nfss->nfs_client,
d_id);
de->od.od = od;
d = nfs4_insert_deviceid_node(&de->id_node);
n = container_of(d, struct objio_dev_ent, id_node);
if (n != de) {
dprintk("%s: Race with other n->od=%p\n", __func__, n->od.od);
objio_free_deviceid_node(&de->id_node);
de = n;
}
return de;
}
struct objio_segment {
struct pnfs_layout_segment lseg;
struct ore_layout layout;
struct ore_components oc;
};
static inline struct objio_segment *
OBJIO_LSEG(struct pnfs_layout_segment *lseg)
{
return container_of(lseg, struct objio_segment, lseg);
}
struct objio_state {
/* Generic layer */
struct objlayout_io_res oir;
bool sync;
/*FIXME: Support for extra_bytes at ore_get_rw_state() */
struct ore_io_state *ios;
};
/* Send and wait for a get_device_info of devices in the layout,
then look them up with the osd_initiator library */
static int objio_devices_lookup(struct pnfs_layout_hdr *pnfslay,
struct objio_segment *objio_seg, unsigned c, struct nfs4_deviceid *d_id,
gfp_t gfp_flags)
{
struct pnfs_osd_deviceaddr *deviceaddr;
struct objio_dev_ent *ode;
struct osd_dev *od;
struct osd_dev_info odi;
bool retry_flag = true;
int err;
ode = _dev_list_find(NFS_SERVER(pnfslay->plh_inode), d_id);
if (ode) {
objio_seg->oc.ods[c] = &ode->od; /* must use container_of */
return 0;
}
err = objlayout_get_deviceinfo(pnfslay, d_id, &deviceaddr, gfp_flags);
if (unlikely(err)) {
dprintk("%s: objlayout_get_deviceinfo dev(%llx:%llx) =>%d\n",
__func__, _DEVID_LO(d_id), _DEVID_HI(d_id), err);
return err;
}
odi.systemid_len = deviceaddr->oda_systemid.len;
if (odi.systemid_len > sizeof(odi.systemid)) {
dprintk("%s: odi.systemid_len > sizeof(systemid=%zd)\n",
__func__, sizeof(odi.systemid));
err = -EINVAL;
goto out;
} else if (odi.systemid_len)
memcpy(odi.systemid, deviceaddr->oda_systemid.data,
odi.systemid_len);
odi.osdname_len = deviceaddr->oda_osdname.len;
odi.osdname = (u8 *)deviceaddr->oda_osdname.data;
if (!odi.osdname_len && !odi.systemid_len) {
dprintk("%s: !odi.osdname_len && !odi.systemid_len\n",
__func__);
err = -ENODEV;
goto out;
}
retry_lookup:
od = osduld_info_lookup(&odi);
if (unlikely(IS_ERR(od))) {
err = PTR_ERR(od);
dprintk("%s: osduld_info_lookup => %d\n", __func__, err);
if (err == -ENODEV && retry_flag) {
err = objlayout_autologin(deviceaddr);
if (likely(!err)) {
retry_flag = false;
goto retry_lookup;
}
}
goto out;
}
ode = _dev_list_add(NFS_SERVER(pnfslay->plh_inode), d_id, od,
gfp_flags);
objio_seg->oc.ods[c] = &ode->od; /* must use container_of */
dprintk("Adding new dev_id(%llx:%llx)\n",
_DEVID_LO(d_id), _DEVID_HI(d_id));
out:
objlayout_put_deviceinfo(deviceaddr);
return err;
}
static void copy_single_comp(struct ore_components *oc, unsigned c,
struct pnfs_osd_object_cred *src_comp)
{
struct ore_comp *ocomp = &oc->comps[c];
WARN_ON(src_comp->oc_cap_key.cred_len > 0); /* libosd is NO_SEC only */
WARN_ON(src_comp->oc_cap.cred_len > sizeof(ocomp->cred));
ocomp->obj.partition = src_comp->oc_object_id.oid_partition_id;
ocomp->obj.id = src_comp->oc_object_id.oid_object_id;
memcpy(ocomp->cred, src_comp->oc_cap.cred, sizeof(ocomp->cred));
}
static int __alloc_objio_seg(unsigned numdevs, gfp_t gfp_flags,
struct objio_segment **pseg)
{
/* This is the in memory structure of the objio_segment
*
* struct __alloc_objio_segment {
* struct objio_segment olseg;
* struct ore_dev *ods[numdevs];
* struct ore_comp comps[numdevs];
* } *aolseg;
* NOTE: The code as above compiles and runs perfectly. It is elegant,
* type safe and compact. At some Past time Linus has decided he does not
* like variable length arrays, For the sake of this principal we uglify
* the code as below.
*/
struct objio_segment *lseg;
size_t lseg_size = sizeof(*lseg) +
numdevs * sizeof(lseg->oc.ods[0]) +
numdevs * sizeof(*lseg->oc.comps);
lseg = kzalloc(lseg_size, gfp_flags);
if (unlikely(!lseg)) {
dprintk("%s: Faild allocation numdevs=%d size=%zd\n", __func__,
numdevs, lseg_size);
return -ENOMEM;
}
lseg->oc.numdevs = numdevs;
lseg->oc.single_comp = EC_MULTPLE_COMPS;
lseg->oc.ods = (void *)(lseg + 1);
lseg->oc.comps = (void *)(lseg->oc.ods + numdevs);
*pseg = lseg;
return 0;
}
int objio_alloc_lseg(struct pnfs_layout_segment **outp,
struct pnfs_layout_hdr *pnfslay,
struct pnfs_layout_range *range,
struct xdr_stream *xdr,
gfp_t gfp_flags)
{
struct objio_segment *objio_seg;
struct pnfs_osd_xdr_decode_layout_iter iter;
struct pnfs_osd_layout layout;
struct pnfs_osd_object_cred src_comp;
unsigned cur_comp;
int err;
err = pnfs_osd_xdr_decode_layout_map(&layout, &iter, xdr);
if (unlikely(err))
return err;
err = __alloc_objio_seg(layout.olo_num_comps, gfp_flags, &objio_seg);
if (unlikely(err))
return err;
objio_seg->layout.stripe_unit = layout.olo_map.odm_stripe_unit;
objio_seg->layout.group_width = layout.olo_map.odm_group_width;
objio_seg->layout.group_depth = layout.olo_map.odm_group_depth;
objio_seg->layout.mirrors_p1 = layout.olo_map.odm_mirror_cnt + 1;
objio_seg->layout.raid_algorithm = layout.olo_map.odm_raid_algorithm;
err = ore_verify_layout(layout.olo_map.odm_num_comps,
&objio_seg->layout);
if (unlikely(err))
goto err;
objio_seg->oc.first_dev = layout.olo_comps_index;
cur_comp = 0;
while (pnfs_osd_xdr_decode_layout_comp(&src_comp, &iter, xdr, &err)) {
copy_single_comp(&objio_seg->oc, cur_comp, &src_comp);
err = objio_devices_lookup(pnfslay, objio_seg, cur_comp,
&src_comp.oc_object_id.oid_device_id,
gfp_flags);
if (err)
goto err;
++cur_comp;
}
/* pnfs_osd_xdr_decode_layout_comp returns false on error */
if (unlikely(err))
goto err;
*outp = &objio_seg->lseg;
return 0;
err:
kfree(objio_seg);
dprintk("%s: Error: return %d\n", __func__, err);
*outp = NULL;
return err;
}
void objio_free_lseg(struct pnfs_layout_segment *lseg)
{
int i;
struct objio_segment *objio_seg = OBJIO_LSEG(lseg);
for (i = 0; i < objio_seg->oc.numdevs; i++) {
struct ore_dev *od = objio_seg->oc.ods[i];
struct objio_dev_ent *ode;
if (!od)
break;
ode = container_of(od, typeof(*ode), od);
nfs4_put_deviceid_node(&ode->id_node);
}
kfree(objio_seg);
}
static int
objio_alloc_io_state(struct pnfs_layout_hdr *pnfs_layout_type, bool is_reading,
struct pnfs_layout_segment *lseg, struct page **pages, unsigned pgbase,
loff_t offset, size_t count, void *rpcdata, gfp_t gfp_flags,
struct objio_state **outp)
{
struct objio_segment *objio_seg = OBJIO_LSEG(lseg);
struct ore_io_state *ios;
int ret;
struct __alloc_objio_state {
struct objio_state objios;
struct pnfs_osd_ioerr ioerrs[objio_seg->oc.numdevs];
} *aos;
aos = kzalloc(sizeof(*aos), gfp_flags);
if (unlikely(!aos))
return -ENOMEM;
objlayout_init_ioerrs(&aos->objios.oir, objio_seg->oc.numdevs,
aos->ioerrs, rpcdata, pnfs_layout_type);
ret = ore_get_rw_state(&objio_seg->layout, &objio_seg->oc, is_reading,
offset, count, &ios);
if (unlikely(ret)) {
kfree(aos);
return ret;
}
ios->pages = pages;
ios->pgbase = pgbase;
ios->private = aos;
BUG_ON(ios->nr_pages > (pgbase + count + PAGE_SIZE - 1) >> PAGE_SHIFT);
aos->objios.sync = 0;
aos->objios.ios = ios;
*outp = &aos->objios;
return 0;
}
void objio_free_result(struct objlayout_io_res *oir)
{
struct objio_state *objios = container_of(oir, struct objio_state, oir);
ore_put_io_state(objios->ios);
kfree(objios);
}
enum pnfs_osd_errno osd_pri_2_pnfs_err(enum osd_err_priority oep)
{
switch (oep) {
case OSD_ERR_PRI_NO_ERROR:
return (enum pnfs_osd_errno)0;
case OSD_ERR_PRI_CLEAR_PAGES:
BUG_ON(1);
return 0;
case OSD_ERR_PRI_RESOURCE:
return PNFS_OSD_ERR_RESOURCE;
case OSD_ERR_PRI_BAD_CRED:
return PNFS_OSD_ERR_BAD_CRED;
case OSD_ERR_PRI_NO_ACCESS:
return PNFS_OSD_ERR_NO_ACCESS;
case OSD_ERR_PRI_UNREACHABLE:
return PNFS_OSD_ERR_UNREACHABLE;
case OSD_ERR_PRI_NOT_FOUND:
return PNFS_OSD_ERR_NOT_FOUND;
case OSD_ERR_PRI_NO_SPACE:
return PNFS_OSD_ERR_NO_SPACE;
default:
WARN_ON(1);
/* fallthrough */
case OSD_ERR_PRI_EIO:
return PNFS_OSD_ERR_EIO;
}
}
static void __on_dev_error(struct ore_io_state *ios,
struct ore_dev *od, unsigned dev_index, enum osd_err_priority oep,
u64 dev_offset, u64 dev_len)
{
struct objio_state *objios = ios->private;
struct pnfs_osd_objid pooid;
struct objio_dev_ent *ode = container_of(od, typeof(*ode), od);
/* FIXME: what to do with more-then-one-group layouts. We need to
* translate from ore_io_state index to oc->comps index
*/
unsigned comp = dev_index;
pooid.oid_device_id = ode->id_node.deviceid;
pooid.oid_partition_id = ios->oc->comps[comp].obj.partition;
pooid.oid_object_id = ios->oc->comps[comp].obj.id;
objlayout_io_set_result(&objios->oir, comp,
&pooid, osd_pri_2_pnfs_err(oep),
dev_offset, dev_len, !ios->reading);
}
/*
* read
*/
static void _read_done(struct ore_io_state *ios, void *private)
{
struct objio_state *objios = private;
ssize_t status;
int ret = ore_check_io(ios, &__on_dev_error);
/* FIXME: _io_free(ios) can we dealocate the libosd resources; */
if (likely(!ret))
status = ios->length;
else
status = ret;
objlayout_read_done(&objios->oir, status, objios->sync);
}
int objio_read_pagelist(struct nfs_read_data *rdata)
{
struct nfs_pgio_header *hdr = rdata->header;
struct objio_state *objios;
int ret;
ret = objio_alloc_io_state(NFS_I(hdr->inode)->layout, true,
hdr->lseg, rdata->args.pages, rdata->args.pgbase,
rdata->args.offset, rdata->args.count, rdata,
GFP_KERNEL, &objios);
if (unlikely(ret))
return ret;
objios->ios->done = _read_done;
dprintk("%s: offset=0x%llx length=0x%x\n", __func__,
rdata->args.offset, rdata->args.count);
ret = ore_read(objios->ios);
if (unlikely(ret))
objio_free_result(&objios->oir);
return ret;
}
/*
* write
*/
static void _write_done(struct ore_io_state *ios, void *private)
{
struct objio_state *objios = private;
ssize_t status;
int ret = ore_check_io(ios, &__on_dev_error);
/* FIXME: _io_free(ios) can we dealocate the libosd resources; */
if (likely(!ret)) {
/* FIXME: should be based on the OSD's persistence model
* See OSD2r05 Section 4.13 Data persistence model */
objios->oir.committed = NFS_FILE_SYNC;
status = ios->length;
} else {
status = ret;
}
objlayout_write_done(&objios->oir, status, objios->sync);
}
static struct page *__r4w_get_page(void *priv, u64 offset, bool *uptodate)
{
struct objio_state *objios = priv;
struct nfs_write_data *wdata = objios->oir.rpcdata;
struct address_space *mapping = wdata->header->inode->i_mapping;
pgoff_t index = offset / PAGE_SIZE;
struct page *page;
loff_t i_size = i_size_read(wdata->header->inode);
if (offset >= i_size) {
*uptodate = true;
dprintk("%s: g_zero_page index=0x%lx\n", __func__, index);
return ZERO_PAGE(0);
}
page = find_get_page(mapping, index);
if (!page) {
page = find_or_create_page(mapping, index, GFP_NOFS);
if (unlikely(!page)) {
dprintk("%s: grab_cache_page Failed index=0x%lx\n",
__func__, index);
return NULL;
}
unlock_page(page);
}
if (PageDirty(page) || PageWriteback(page))
*uptodate = true;
else
*uptodate = PageUptodate(page);
dprintk("%s: index=0x%lx uptodate=%d\n", __func__, index, *uptodate);
return page;
}
static void __r4w_put_page(void *priv, struct page *page)
{
dprintk("%s: index=0x%lx\n", __func__,
(page == ZERO_PAGE(0)) ? -1UL : page->index);
if (ZERO_PAGE(0) != page)
page_cache_release(page);
return;
}
static const struct _ore_r4w_op _r4w_op = {
.get_page = &__r4w_get_page,
.put_page = &__r4w_put_page,
};
int objio_write_pagelist(struct nfs_write_data *wdata, int how)
{
struct nfs_pgio_header *hdr = wdata->header;
struct objio_state *objios;
int ret;
ret = objio_alloc_io_state(NFS_I(hdr->inode)->layout, false,
hdr->lseg, wdata->args.pages, wdata->args.pgbase,
wdata->args.offset, wdata->args.count, wdata, GFP_NOFS,
&objios);
if (unlikely(ret))
return ret;
objios->sync = 0 != (how & FLUSH_SYNC);
objios->ios->r4w = &_r4w_op;
if (!objios->sync)
objios->ios->done = _write_done;
dprintk("%s: offset=0x%llx length=0x%x\n", __func__,
wdata->args.offset, wdata->args.count);
ret = ore_write(objios->ios);
if (unlikely(ret)) {
objio_free_result(&objios->oir);
return ret;
}
if (objios->sync)
_write_done(objios->ios, objios);
return 0;
}
static bool objio_pg_test(struct nfs_pageio_descriptor *pgio,
struct nfs_page *prev, struct nfs_page *req)
{
if (!pnfs_generic_pg_test(pgio, prev, req))
return false;
return pgio->pg_count + req->wb_bytes <=
(unsigned long)pgio->pg_layout_private;
}
void objio_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
pnfs_generic_pg_init_read(pgio, req);
if (unlikely(pgio->pg_lseg == NULL))
return; /* Not pNFS */
pgio->pg_layout_private = (void *)
OBJIO_LSEG(pgio->pg_lseg)->layout.max_io_length;
}
static bool aligned_on_raid_stripe(u64 offset, struct ore_layout *layout,
unsigned long *stripe_end)
{
u32 stripe_off;
unsigned stripe_size;
if (layout->raid_algorithm == PNFS_OSD_RAID_0)
return true;
stripe_size = layout->stripe_unit *
(layout->group_width - layout->parity);
div_u64_rem(offset, stripe_size, &stripe_off);
if (!stripe_off)
return true;
*stripe_end = stripe_size - stripe_off;
return false;
}
void objio_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
unsigned long stripe_end = 0;
pnfs_generic_pg_init_write(pgio, req);
if (unlikely(pgio->pg_lseg == NULL))
return; /* Not pNFS */
if (req->wb_offset ||
!aligned_on_raid_stripe(req->wb_index * PAGE_SIZE,
&OBJIO_LSEG(pgio->pg_lseg)->layout,
&stripe_end)) {
pgio->pg_layout_private = (void *)stripe_end;
} else {
pgio->pg_layout_private = (void *)
OBJIO_LSEG(pgio->pg_lseg)->layout.max_io_length;
}
}
static const struct nfs_pageio_ops objio_pg_read_ops = {
.pg_init = objio_init_read,
.pg_test = objio_pg_test,
.pg_doio = pnfs_generic_pg_readpages,
};
static const struct nfs_pageio_ops objio_pg_write_ops = {
.pg_init = objio_init_write,
.pg_test = objio_pg_test,
.pg_doio = pnfs_generic_pg_writepages,
};
static struct pnfs_layoutdriver_type objlayout_type = {
.id = LAYOUT_OSD2_OBJECTS,
.name = "LAYOUT_OSD2_OBJECTS",
.flags = PNFS_LAYOUTRET_ON_SETATTR |
PNFS_LAYOUTRET_ON_ERROR,
.alloc_layout_hdr = objlayout_alloc_layout_hdr,
.free_layout_hdr = objlayout_free_layout_hdr,
.alloc_lseg = objlayout_alloc_lseg,
.free_lseg = objlayout_free_lseg,
.read_pagelist = objlayout_read_pagelist,
.write_pagelist = objlayout_write_pagelist,
.pg_read_ops = &objio_pg_read_ops,
.pg_write_ops = &objio_pg_write_ops,
.free_deviceid_node = objio_free_deviceid_node,
.encode_layoutcommit = objlayout_encode_layoutcommit,
.encode_layoutreturn = objlayout_encode_layoutreturn,
};
MODULE_DESCRIPTION("pNFS Layout Driver for OSD2 objects");
MODULE_AUTHOR("Benny Halevy <bhalevy@panasas.com>");
MODULE_LICENSE("GPL");
static int __init
objlayout_init(void)
{
int ret = pnfs_register_layoutdriver(&objlayout_type);
if (ret)
printk(KERN_INFO
"NFS: %s: Registering OSD pNFS Layout Driver failed: error=%d\n",
__func__, ret);
else
printk(KERN_INFO "NFS: %s: Registered OSD pNFS Layout Driver\n",
__func__);
return ret;
}
static void __exit
objlayout_exit(void)
{
pnfs_unregister_layoutdriver(&objlayout_type);
printk(KERN_INFO "NFS: %s: Unregistered OSD pNFS Layout Driver\n",
__func__);
}
MODULE_ALIAS("nfs-layouttype4-2");
module_init(objlayout_init);
module_exit(objlayout_exit);