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nest-open-source / nest-learning-thermostat / 5.7.1 / linux-imx-ul / refs/heads/master / . / drivers / staging / lustre / lustre / osc / osc_cache.c
blob: d44b3d4ffe4d152ff2e32b3740a3d2aa9790ddd8 [file] [log] [blame]
/*
* GPL HEADER START
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 only,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is included
* in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; If not, see
* http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
* GPL HEADER END
*/
/*
* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
*
* Copyright (c) 2012, Intel Corporation.
*
*/
/*
* This file is part of Lustre, http://www.lustre.org/
* Lustre is a trademark of Sun Microsystems, Inc.
*
* osc cache management.
*
* Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
*/
#define DEBUG_SUBSYSTEM S_OSC
#include "osc_cl_internal.h"
#include "osc_internal.h"
static int extent_debug; /* set it to be true for more debug */
static void osc_update_pending(struct osc_object *obj, int cmd, int delta);
static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
int state);
static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
struct osc_async_page *oap, int sent, int rc);
static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
int cmd);
static int osc_refresh_count(const struct lu_env *env,
struct osc_async_page *oap, int cmd);
static int osc_io_unplug_async(const struct lu_env *env,
struct client_obd *cli, struct osc_object *osc);
static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
unsigned int lost_grant);
static void osc_extent_tree_dump0(int level, struct osc_object *obj,
const char *func, int line);
#define osc_extent_tree_dump(lvl, obj) \
osc_extent_tree_dump0(lvl, obj, __func__, __LINE__)
/** \addtogroup osc
* @{
*/
/* ------------------ osc extent ------------------ */
static inline char *ext_flags(struct osc_extent *ext, char *flags)
{
char *buf = flags;
*buf++ = ext->oe_rw ? 'r' : 'w';
if (ext->oe_intree)
*buf++ = 'i';
if (ext->oe_srvlock)
*buf++ = 's';
if (ext->oe_hp)
*buf++ = 'h';
if (ext->oe_urgent)
*buf++ = 'u';
if (ext->oe_memalloc)
*buf++ = 'm';
if (ext->oe_trunc_pending)
*buf++ = 't';
if (ext->oe_fsync_wait)
*buf++ = 'Y';
*buf = 0;
return flags;
}
static inline char list_empty_marker(struct list_head *list)
{
return list_empty(list) ? '-' : '+';
}
#define EXTSTR "[%lu -> %lu/%lu]"
#define EXTPARA(ext) (ext)->oe_start, (ext)->oe_end, (ext)->oe_max_end
static const char *oes_strings[] = {
"inv", "active", "cache", "locking", "lockdone", "rpc", "trunc", NULL };
#define OSC_EXTENT_DUMP(lvl, extent, fmt, ...) do { \
struct osc_extent *__ext = (extent); \
char __buf[16]; \
\
CDEBUG(lvl, \
"extent %p@{" EXTSTR ", " \
"[%d|%d|%c|%s|%s|%p], [%d|%d|%c|%c|%p|%u|%p]} " fmt, \
/* ----- extent part 0 ----- */ \
__ext, EXTPARA(__ext), \
/* ----- part 1 ----- */ \
atomic_read(&__ext->oe_refc), \
atomic_read(&__ext->oe_users), \
list_empty_marker(&__ext->oe_link), \
oes_strings[__ext->oe_state], ext_flags(__ext, __buf), \
__ext->oe_obj, \
/* ----- part 2 ----- */ \
__ext->oe_grants, __ext->oe_nr_pages, \
list_empty_marker(&__ext->oe_pages), \
waitqueue_active(&__ext->oe_waitq) ? '+' : '-', \
__ext->oe_osclock, __ext->oe_mppr, __ext->oe_owner, \
/* ----- part 4 ----- */ \
## __VA_ARGS__); \
} while (0)
#undef EASSERTF
#define EASSERTF(expr, ext, fmt, args...) do { \
if (!(expr)) { \
OSC_EXTENT_DUMP(D_ERROR, (ext), fmt, ##args); \
osc_extent_tree_dump(D_ERROR, (ext)->oe_obj); \
LASSERT(expr); \
} \
} while (0)
#undef EASSERT
#define EASSERT(expr, ext) EASSERTF(expr, ext, "\n")
static inline struct osc_extent *rb_extent(struct rb_node *n)
{
if (n == NULL)
return NULL;
return container_of(n, struct osc_extent, oe_node);
}
static inline struct osc_extent *next_extent(struct osc_extent *ext)
{
if (ext == NULL)
return NULL;
LASSERT(ext->oe_intree);
return rb_extent(rb_next(&ext->oe_node));
}
static inline struct osc_extent *prev_extent(struct osc_extent *ext)
{
if (ext == NULL)
return NULL;
LASSERT(ext->oe_intree);
return rb_extent(rb_prev(&ext->oe_node));
}
static inline struct osc_extent *first_extent(struct osc_object *obj)
{
return rb_extent(rb_first(&obj->oo_root));
}
/* object must be locked by caller. */
static int osc_extent_sanity_check0(struct osc_extent *ext,
const char *func, const int line)
{
struct osc_object *obj = ext->oe_obj;
struct osc_async_page *oap;
int page_count;
int rc = 0;
if (!osc_object_is_locked(obj)) {
rc = 9;
goto out;
}
if (ext->oe_state >= OES_STATE_MAX) {
rc = 10;
goto out;
}
if (atomic_read(&ext->oe_refc) <= 0) {
rc = 20;
goto out;
}
if (atomic_read(&ext->oe_refc) < atomic_read(&ext->oe_users)) {
rc = 30;
goto out;
}
switch (ext->oe_state) {
case OES_INV:
if (ext->oe_nr_pages > 0 || !list_empty(&ext->oe_pages))
rc = 35;
else
rc = 0;
goto out;
case OES_ACTIVE:
if (atomic_read(&ext->oe_users) == 0) {
rc = 40;
goto out;
}
if (ext->oe_hp) {
rc = 50;
goto out;
}
if (ext->oe_fsync_wait && !ext->oe_urgent) {
rc = 55;
goto out;
}
break;
case OES_CACHE:
if (ext->oe_grants == 0) {
rc = 60;
goto out;
}
if (ext->oe_fsync_wait && !ext->oe_urgent && !ext->oe_hp) {
rc = 65;
goto out;
}
default:
if (atomic_read(&ext->oe_users) > 0) {
rc = 70;
goto out;
}
}
if (ext->oe_max_end < ext->oe_end || ext->oe_end < ext->oe_start) {
rc = 80;
goto out;
}
if (ext->oe_osclock == NULL && ext->oe_grants > 0) {
rc = 90;
goto out;
}
if (ext->oe_osclock) {
struct cl_lock_descr *descr;
descr = &ext->oe_osclock->cll_descr;
if (!(descr->cld_start <= ext->oe_start &&
descr->cld_end >= ext->oe_max_end)) {
rc = 100;
goto out;
}
}
if (ext->oe_nr_pages > ext->oe_mppr) {
rc = 105;
goto out;
}
/* Do not verify page list if extent is in RPC. This is because an
* in-RPC extent is supposed to be exclusively accessible w/o lock. */
if (ext->oe_state > OES_CACHE) {
rc = 0;
goto out;
}
if (!extent_debug) {
rc = 0;
goto out;
}
page_count = 0;
list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
pgoff_t index = oap2cl_page(oap)->cp_index;
++page_count;
if (index > ext->oe_end || index < ext->oe_start) {
rc = 110;
goto out;
}
}
if (page_count != ext->oe_nr_pages) {
rc = 120;
goto out;
}
out:
if (rc != 0)
OSC_EXTENT_DUMP(D_ERROR, ext,
"%s:%d sanity check %p failed with rc = %d\n",
func, line, ext, rc);
return rc;
}
#define sanity_check_nolock(ext) \
osc_extent_sanity_check0(ext, __func__, __LINE__)
#define sanity_check(ext) ({ \
int __res; \
osc_object_lock((ext)->oe_obj); \
__res = sanity_check_nolock(ext); \
osc_object_unlock((ext)->oe_obj); \
__res; \
})
/**
* sanity check - to make sure there is no overlapped extent in the tree.
*/
static int osc_extent_is_overlapped(struct osc_object *obj,
struct osc_extent *ext)
{
struct osc_extent *tmp;
LASSERT(osc_object_is_locked(obj));
if (!extent_debug)
return 0;
for (tmp = first_extent(obj); tmp != NULL; tmp = next_extent(tmp)) {
if (tmp == ext)
continue;
if (tmp->oe_end >= ext->oe_start &&
tmp->oe_start <= ext->oe_end)
return 1;
}
return 0;
}
static void osc_extent_state_set(struct osc_extent *ext, int state)
{
LASSERT(osc_object_is_locked(ext->oe_obj));
LASSERT(state >= OES_INV && state < OES_STATE_MAX);
/* Never try to sanity check a state changing extent :-) */
/* LASSERT(sanity_check_nolock(ext) == 0); */
/* TODO: validate the state machine */
ext->oe_state = state;
wake_up_all(&ext->oe_waitq);
}
static struct osc_extent *osc_extent_alloc(struct osc_object *obj)
{
struct osc_extent *ext;
OBD_SLAB_ALLOC_PTR_GFP(ext, osc_extent_kmem, GFP_IOFS);
if (ext == NULL)
return NULL;
RB_CLEAR_NODE(&ext->oe_node);
ext->oe_obj = obj;
atomic_set(&ext->oe_refc, 1);
atomic_set(&ext->oe_users, 0);
INIT_LIST_HEAD(&ext->oe_link);
ext->oe_state = OES_INV;
INIT_LIST_HEAD(&ext->oe_pages);
init_waitqueue_head(&ext->oe_waitq);
ext->oe_osclock = NULL;
return ext;
}
static void osc_extent_free(struct osc_extent *ext)
{
OBD_SLAB_FREE_PTR(ext, osc_extent_kmem);
}
static struct osc_extent *osc_extent_get(struct osc_extent *ext)
{
LASSERT(atomic_read(&ext->oe_refc) >= 0);
atomic_inc(&ext->oe_refc);
return ext;
}
static void osc_extent_put(const struct lu_env *env, struct osc_extent *ext)
{
LASSERT(atomic_read(&ext->oe_refc) > 0);
if (atomic_dec_and_test(&ext->oe_refc)) {
LASSERT(list_empty(&ext->oe_link));
LASSERT(atomic_read(&ext->oe_users) == 0);
LASSERT(ext->oe_state == OES_INV);
LASSERT(!ext->oe_intree);
if (ext->oe_osclock) {
cl_lock_put(env, ext->oe_osclock);
ext->oe_osclock = NULL;
}
osc_extent_free(ext);
}
}
/**
* osc_extent_put_trust() is a special version of osc_extent_put() when
* it's known that the caller is not the last user. This is to address the
* problem of lacking of lu_env ;-).
*/
static void osc_extent_put_trust(struct osc_extent *ext)
{
LASSERT(atomic_read(&ext->oe_refc) > 1);
LASSERT(osc_object_is_locked(ext->oe_obj));
atomic_dec(&ext->oe_refc);
}
/**
* Return the extent which includes pgoff @index, or return the greatest
* previous extent in the tree.
*/
static struct osc_extent *osc_extent_search(struct osc_object *obj,
pgoff_t index)
{
struct rb_node *n = obj->oo_root.rb_node;
struct osc_extent *tmp, *p = NULL;
LASSERT(osc_object_is_locked(obj));
while (n != NULL) {
tmp = rb_extent(n);
if (index < tmp->oe_start) {
n = n->rb_left;
} else if (index > tmp->oe_end) {
p = rb_extent(n);
n = n->rb_right;
} else {
return tmp;
}
}
return p;
}
/*
* Return the extent covering @index, otherwise return NULL.
* caller must have held object lock.
*/
static struct osc_extent *osc_extent_lookup(struct osc_object *obj,
pgoff_t index)
{
struct osc_extent *ext;
ext = osc_extent_search(obj, index);
if (ext != NULL && ext->oe_start <= index && index <= ext->oe_end)
return osc_extent_get(ext);
return NULL;
}
/* caller must have held object lock. */
static void osc_extent_insert(struct osc_object *obj, struct osc_extent *ext)
{
struct rb_node **n = &obj->oo_root.rb_node;
struct rb_node *parent = NULL;
struct osc_extent *tmp;
LASSERT(ext->oe_intree == 0);
LASSERT(ext->oe_obj == obj);
LASSERT(osc_object_is_locked(obj));
while (*n != NULL) {
tmp = rb_extent(*n);
parent = *n;
if (ext->oe_end < tmp->oe_start)
n = &(*n)->rb_left;
else if (ext->oe_start > tmp->oe_end)
n = &(*n)->rb_right;
else
EASSERTF(0, tmp, EXTSTR, EXTPARA(ext));
}
rb_link_node(&ext->oe_node, parent, n);
rb_insert_color(&ext->oe_node, &obj->oo_root);
osc_extent_get(ext);
ext->oe_intree = 1;
}
/* caller must have held object lock. */
static void osc_extent_erase(struct osc_extent *ext)
{
struct osc_object *obj = ext->oe_obj;
LASSERT(osc_object_is_locked(obj));
if (ext->oe_intree) {
rb_erase(&ext->oe_node, &obj->oo_root);
ext->oe_intree = 0;
/* rbtree held a refcount */
osc_extent_put_trust(ext);
}
}
static struct osc_extent *osc_extent_hold(struct osc_extent *ext)
{
struct osc_object *obj = ext->oe_obj;
LASSERT(osc_object_is_locked(obj));
LASSERT(ext->oe_state == OES_ACTIVE || ext->oe_state == OES_CACHE);
if (ext->oe_state == OES_CACHE) {
osc_extent_state_set(ext, OES_ACTIVE);
osc_update_pending(obj, OBD_BRW_WRITE, -ext->oe_nr_pages);
}
atomic_inc(&ext->oe_users);
list_del_init(&ext->oe_link);
return osc_extent_get(ext);
}
static void __osc_extent_remove(struct osc_extent *ext)
{
LASSERT(osc_object_is_locked(ext->oe_obj));
LASSERT(list_empty(&ext->oe_pages));
osc_extent_erase(ext);
list_del_init(&ext->oe_link);
osc_extent_state_set(ext, OES_INV);
OSC_EXTENT_DUMP(D_CACHE, ext, "destroyed.\n");
}
static void osc_extent_remove(struct osc_extent *ext)
{
struct osc_object *obj = ext->oe_obj;
osc_object_lock(obj);
__osc_extent_remove(ext);
osc_object_unlock(obj);
}
/**
* This function is used to merge extents to get better performance. It checks
* if @cur and @victim are contiguous at chunk level.
*/
static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
struct osc_extent *victim)
{
struct osc_object *obj = cur->oe_obj;
pgoff_t chunk_start;
pgoff_t chunk_end;
int ppc_bits;
LASSERT(cur->oe_state == OES_CACHE);
LASSERT(osc_object_is_locked(obj));
if (victim == NULL)
return -EINVAL;
if (victim->oe_state != OES_CACHE || victim->oe_fsync_wait)
return -EBUSY;
if (cur->oe_max_end != victim->oe_max_end)
return -ERANGE;
LASSERT(cur->oe_osclock == victim->oe_osclock);
ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_CACHE_SHIFT;
chunk_start = cur->oe_start >> ppc_bits;
chunk_end = cur->oe_end >> ppc_bits;
if (chunk_start != (victim->oe_end >> ppc_bits) + 1 &&
chunk_end + 1 != victim->oe_start >> ppc_bits)
return -ERANGE;
OSC_EXTENT_DUMP(D_CACHE, victim, "will be merged by %p.\n", cur);
cur->oe_start = min(cur->oe_start, victim->oe_start);
cur->oe_end = max(cur->oe_end, victim->oe_end);
cur->oe_grants += victim->oe_grants;
cur->oe_nr_pages += victim->oe_nr_pages;
/* only the following bits are needed to merge */
cur->oe_urgent |= victim->oe_urgent;
cur->oe_memalloc |= victim->oe_memalloc;
list_splice_init(&victim->oe_pages, &cur->oe_pages);
list_del_init(&victim->oe_link);
victim->oe_nr_pages = 0;
osc_extent_get(victim);
__osc_extent_remove(victim);
osc_extent_put(env, victim);
OSC_EXTENT_DUMP(D_CACHE, cur, "after merging %p.\n", victim);
return 0;
}
/**
* Drop user count of osc_extent, and unplug IO asynchronously.
*/
void osc_extent_release(const struct lu_env *env, struct osc_extent *ext)
{
struct osc_object *obj = ext->oe_obj;
LASSERT(atomic_read(&ext->oe_users) > 0);
LASSERT(sanity_check(ext) == 0);
LASSERT(ext->oe_grants > 0);
if (atomic_dec_and_lock(&ext->oe_users, &obj->oo_lock)) {
LASSERT(ext->oe_state == OES_ACTIVE);
if (ext->oe_trunc_pending) {
/* a truncate process is waiting for this extent.
* This may happen due to a race, check
* osc_cache_truncate_start(). */
osc_extent_state_set(ext, OES_TRUNC);
ext->oe_trunc_pending = 0;
} else {
osc_extent_state_set(ext, OES_CACHE);
osc_update_pending(obj, OBD_BRW_WRITE,
ext->oe_nr_pages);
/* try to merge the previous and next extent. */
osc_extent_merge(env, ext, prev_extent(ext));
osc_extent_merge(env, ext, next_extent(ext));
if (ext->oe_urgent)
list_move_tail(&ext->oe_link,
&obj->oo_urgent_exts);
}
osc_object_unlock(obj);
osc_io_unplug_async(env, osc_cli(obj), obj);
}
osc_extent_put(env, ext);
}
static inline int overlapped(struct osc_extent *ex1, struct osc_extent *ex2)
{
return !(ex1->oe_end < ex2->oe_start || ex2->oe_end < ex1->oe_start);
}
/**
* Find or create an extent which includes @index, core function to manage
* extent tree.
*/
struct osc_extent *osc_extent_find(const struct lu_env *env,
struct osc_object *obj, pgoff_t index,
int *grants)
{
struct client_obd *cli = osc_cli(obj);
struct cl_lock *lock;
struct osc_extent *cur;
struct osc_extent *ext;
struct osc_extent *conflict = NULL;
struct osc_extent *found = NULL;
pgoff_t chunk;
pgoff_t max_end;
int max_pages; /* max_pages_per_rpc */
int chunksize;
int ppc_bits; /* pages per chunk bits */
int chunk_mask;
int rc;
cur = osc_extent_alloc(obj);
if (cur == NULL)
return ERR_PTR(-ENOMEM);
lock = cl_lock_at_pgoff(env, osc2cl(obj), index, NULL, 1, 0);
LASSERT(lock != NULL);
LASSERT(lock->cll_descr.cld_mode >= CLM_WRITE);
LASSERT(cli->cl_chunkbits >= PAGE_CACHE_SHIFT);
ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
chunk_mask = ~((1 << ppc_bits) - 1);
chunksize = 1 << cli->cl_chunkbits;
chunk = index >> ppc_bits;
/* align end to rpc edge, rpc size may not be a power 2 integer. */
max_pages = cli->cl_max_pages_per_rpc;
LASSERT((max_pages & ~chunk_mask) == 0);
max_end = index - (index % max_pages) + max_pages - 1;
max_end = min_t(pgoff_t, max_end, lock->cll_descr.cld_end);
/* initialize new extent by parameters so far */
cur->oe_max_end = max_end;
cur->oe_start = index & chunk_mask;
cur->oe_end = ((index + ~chunk_mask + 1) & chunk_mask) - 1;
if (cur->oe_start < lock->cll_descr.cld_start)
cur->oe_start = lock->cll_descr.cld_start;
if (cur->oe_end > max_end)
cur->oe_end = max_end;
cur->oe_osclock = lock;
cur->oe_grants = 0;
cur->oe_mppr = max_pages;
/* grants has been allocated by caller */
LASSERTF(*grants >= chunksize + cli->cl_extent_tax,
"%u/%u/%u.\n", *grants, chunksize, cli->cl_extent_tax);
LASSERTF((max_end - cur->oe_start) < max_pages, EXTSTR, EXTPARA(cur));
restart:
osc_object_lock(obj);
ext = osc_extent_search(obj, cur->oe_start);
if (ext == NULL)
ext = first_extent(obj);
while (ext != NULL) {
loff_t ext_chk_start = ext->oe_start >> ppc_bits;
loff_t ext_chk_end = ext->oe_end >> ppc_bits;
LASSERT(sanity_check_nolock(ext) == 0);
if (chunk > ext_chk_end + 1)
break;
/* if covering by different locks, no chance to match */
if (lock != ext->oe_osclock) {
EASSERTF(!overlapped(ext, cur), ext,
EXTSTR, EXTPARA(cur));
ext = next_extent(ext);
continue;
}
/* discontiguous chunks? */
if (chunk + 1 < ext_chk_start) {
ext = next_extent(ext);
continue;
}
/* ok, from now on, ext and cur have these attrs:
* 1. covered by the same lock
* 2. contiguous at chunk level or overlapping. */
if (overlapped(ext, cur)) {
/* cur is the minimum unit, so overlapping means
* full contain. */
EASSERTF((ext->oe_start <= cur->oe_start &&
ext->oe_end >= cur->oe_end),
ext, EXTSTR, EXTPARA(cur));
if (ext->oe_state > OES_CACHE || ext->oe_fsync_wait) {
/* for simplicity, we wait for this extent to
* finish before going forward. */
conflict = osc_extent_get(ext);
break;
}
found = osc_extent_hold(ext);
break;
}
/* non-overlapped extent */
if (ext->oe_state != OES_CACHE || ext->oe_fsync_wait) {
/* we can't do anything for a non OES_CACHE extent, or
* if there is someone waiting for this extent to be
* flushed, try next one. */
ext = next_extent(ext);
continue;
}
/* check if they belong to the same rpc slot before trying to
* merge. the extents are not overlapped and contiguous at
* chunk level to get here. */
if (ext->oe_max_end != max_end) {
/* if they don't belong to the same RPC slot or
* max_pages_per_rpc has ever changed, do not merge. */
ext = next_extent(ext);
continue;
}
/* it's required that an extent must be contiguous at chunk
* level so that we know the whole extent is covered by grant
* (the pages in the extent are NOT required to be contiguous).
* Otherwise, it will be too much difficult to know which
* chunks have grants allocated. */
/* try to do front merge - extend ext's start */
if (chunk + 1 == ext_chk_start) {
/* ext must be chunk size aligned */
EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
/* pull ext's start back to cover cur */
ext->oe_start = cur->oe_start;
ext->oe_grants += chunksize;
*grants -= chunksize;
found = osc_extent_hold(ext);
} else if (chunk == ext_chk_end + 1) {
/* rear merge */
ext->oe_end = cur->oe_end;
ext->oe_grants += chunksize;
*grants -= chunksize;
/* try to merge with the next one because we just fill
* in a gap */
if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
/* we can save extent tax from next extent */
*grants += cli->cl_extent_tax;
found = osc_extent_hold(ext);
}
if (found != NULL)
break;
ext = next_extent(ext);
}
osc_extent_tree_dump(D_CACHE, obj);
if (found != NULL) {
LASSERT(conflict == NULL);
if (!IS_ERR(found)) {
LASSERT(found->oe_osclock == cur->oe_osclock);
OSC_EXTENT_DUMP(D_CACHE, found,
"found caching ext for %lu.\n", index);
}
} else if (conflict == NULL) {
/* create a new extent */
EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
cur->oe_grants = chunksize + cli->cl_extent_tax;
*grants -= cur->oe_grants;
LASSERT(*grants >= 0);
cur->oe_state = OES_CACHE;
found = osc_extent_hold(cur);
osc_extent_insert(obj, cur);
OSC_EXTENT_DUMP(D_CACHE, cur, "add into tree %lu/%lu.\n",
index, lock->cll_descr.cld_end);
}
osc_object_unlock(obj);
if (conflict != NULL) {
LASSERT(found == NULL);
/* waiting for IO to finish. Please notice that it's impossible
* to be an OES_TRUNC extent. */
rc = osc_extent_wait(env, conflict, OES_INV);
osc_extent_put(env, conflict);
conflict = NULL;
if (rc < 0) {
found = ERR_PTR(rc);
goto out;
}
goto restart;
}
out:
osc_extent_put(env, cur);
LASSERT(*grants >= 0);
return found;
}
/**
* Called when IO is finished to an extent.
*/
int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
int sent, int rc)
{
struct client_obd *cli = osc_cli(ext->oe_obj);
struct osc_async_page *oap;
struct osc_async_page *tmp;
int nr_pages = ext->oe_nr_pages;
int lost_grant = 0;
int blocksize = cli->cl_import->imp_obd->obd_osfs.os_bsize ? : 4096;
__u64 last_off = 0;
int last_count = -1;
OSC_EXTENT_DUMP(D_CACHE, ext, "extent finished.\n");
ext->oe_rc = rc ?: ext->oe_nr_pages;
EASSERT(ergo(rc == 0, ext->oe_state == OES_RPC), ext);
list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
oap_pending_item) {
list_del_init(&oap->oap_rpc_item);
list_del_init(&oap->oap_pending_item);
if (last_off <= oap->oap_obj_off) {
last_off = oap->oap_obj_off;
last_count = oap->oap_count;
}
--ext->oe_nr_pages;
osc_ap_completion(env, cli, oap, sent, rc);
}
EASSERT(ext->oe_nr_pages == 0, ext);
if (!sent) {
lost_grant = ext->oe_grants;
} else if (blocksize < PAGE_CACHE_SIZE &&
last_count != PAGE_CACHE_SIZE) {
/* For short writes we shouldn't count parts of pages that
* span a whole chunk on the OST side, or our accounting goes
* wrong. Should match the code in filter_grant_check. */
int offset = oap->oap_page_off & ~CFS_PAGE_MASK;
int count = oap->oap_count + (offset & (blocksize - 1));
int end = (offset + oap->oap_count) & (blocksize - 1);
if (end)
count += blocksize - end;
lost_grant = PAGE_CACHE_SIZE - count;
}
if (ext->oe_grants > 0)
osc_free_grant(cli, nr_pages, lost_grant);
osc_extent_remove(ext);
/* put the refcount for RPC */
osc_extent_put(env, ext);
return 0;
}
static int extent_wait_cb(struct osc_extent *ext, int state)
{
int ret;
osc_object_lock(ext->oe_obj);
ret = ext->oe_state == state;
osc_object_unlock(ext->oe_obj);
return ret;
}
/**
* Wait for the extent's state to become @state.
*/
static int osc_extent_wait(const struct lu_env *env, struct osc_extent *ext,
int state)
{
struct osc_object *obj = ext->oe_obj;
struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(600), NULL,
LWI_ON_SIGNAL_NOOP, NULL);
int rc = 0;
osc_object_lock(obj);
LASSERT(sanity_check_nolock(ext) == 0);
/* `Kick' this extent only if the caller is waiting for it to be
* written out. */
if (state == OES_INV && !ext->oe_urgent && !ext->oe_hp &&
!ext->oe_trunc_pending) {
if (ext->oe_state == OES_ACTIVE) {
ext->oe_urgent = 1;
} else if (ext->oe_state == OES_CACHE) {
ext->oe_urgent = 1;
osc_extent_hold(ext);
rc = 1;
}
}
osc_object_unlock(obj);
if (rc == 1)
osc_extent_release(env, ext);
/* wait for the extent until its state becomes @state */
rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state), &lwi);
if (rc == -ETIMEDOUT) {
OSC_EXTENT_DUMP(D_ERROR, ext,
"%s: wait ext to %d timedout, recovery in progress?\n",
osc_export(obj)->exp_obd->obd_name, state);
lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
rc = l_wait_event(ext->oe_waitq, extent_wait_cb(ext, state),
&lwi);
}
if (rc == 0 && ext->oe_rc < 0)
rc = ext->oe_rc;
return rc;
}
/**
* Discard pages with index greater than @size. If @ext is overlapped with
* @size, then partial truncate happens.
*/
static int osc_extent_truncate(struct osc_extent *ext, pgoff_t trunc_index,
bool partial)
{
struct cl_env_nest nest;
struct lu_env *env;
struct cl_io *io;
struct osc_object *obj = ext->oe_obj;
struct client_obd *cli = osc_cli(obj);
struct osc_async_page *oap;
struct osc_async_page *tmp;
int pages_in_chunk = 0;
int ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
__u64 trunc_chunk = trunc_index >> ppc_bits;
int grants = 0;
int nr_pages = 0;
int rc = 0;
LASSERT(sanity_check(ext) == 0);
EASSERT(ext->oe_state == OES_TRUNC, ext);
EASSERT(!ext->oe_urgent, ext);
/* Request new lu_env.
* We can't use that env from osc_cache_truncate_start() because
* it's from lov_io_sub and not fully initialized. */
env = cl_env_nested_get(&nest);
io = &osc_env_info(env)->oti_io;
io->ci_obj = cl_object_top(osc2cl(obj));
rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
if (rc < 0)
goto out;
/* discard all pages with index greater then trunc_index */
list_for_each_entry_safe(oap, tmp, &ext->oe_pages,
oap_pending_item) {
struct cl_page *sub = oap2cl_page(oap);
struct cl_page *page = cl_page_top(sub);
LASSERT(list_empty(&oap->oap_rpc_item));
/* only discard the pages with their index greater than
* trunc_index, and ... */
if (sub->cp_index < trunc_index ||
(sub->cp_index == trunc_index && partial)) {
/* accounting how many pages remaining in the chunk
* so that we can calculate grants correctly. */
if (sub->cp_index >> ppc_bits == trunc_chunk)
++pages_in_chunk;
continue;
}
list_del_init(&oap->oap_pending_item);
cl_page_get(page);
lu_ref_add(&page->cp_reference, "truncate", current);
if (cl_page_own(env, io, page) == 0) {
cl_page_unmap(env, io, page);
cl_page_discard(env, io, page);
cl_page_disown(env, io, page);
} else {
LASSERT(page->cp_state == CPS_FREEING);
LASSERT(0);
}
lu_ref_del(&page->cp_reference, "truncate", current);
cl_page_put(env, page);
--ext->oe_nr_pages;
++nr_pages;
}
EASSERTF(ergo(ext->oe_start >= trunc_index + !!partial,
ext->oe_nr_pages == 0),
ext, "trunc_index %lu, partial %d\n", trunc_index, partial);
osc_object_lock(obj);
if (ext->oe_nr_pages == 0) {
LASSERT(pages_in_chunk == 0);
grants = ext->oe_grants;
ext->oe_grants = 0;
} else { /* calculate how many grants we can free */
int chunks = (ext->oe_end >> ppc_bits) - trunc_chunk;
pgoff_t last_index;
/* if there is no pages in this chunk, we can also free grants
* for the last chunk */
if (pages_in_chunk == 0) {
/* if this is the 1st chunk and no pages in this chunk,
* ext->oe_nr_pages must be zero, so we should be in
* the other if-clause. */
LASSERT(trunc_chunk > 0);
--trunc_chunk;
++chunks;
}
/* this is what we can free from this extent */
grants = chunks << cli->cl_chunkbits;
ext->oe_grants -= grants;
last_index = ((trunc_chunk + 1) << ppc_bits) - 1;
ext->oe_end = min(last_index, ext->oe_max_end);
LASSERT(ext->oe_end >= ext->oe_start);
LASSERT(ext->oe_grants > 0);
}
osc_object_unlock(obj);
if (grants > 0 || nr_pages > 0)
osc_free_grant(cli, nr_pages, grants);
out:
cl_io_fini(env, io);
cl_env_nested_put(&nest, env);
return rc;
}
/**
* This function is used to make the extent prepared for transfer.
* A race with flushing page - ll_writepage() has to be handled cautiously.
*/
static int osc_extent_make_ready(const struct lu_env *env,
struct osc_extent *ext)
{
struct osc_async_page *oap;
struct osc_async_page *last = NULL;
struct osc_object *obj = ext->oe_obj;
int page_count = 0;
int rc;
/* we're going to grab page lock, so object lock must not be taken. */
LASSERT(sanity_check(ext) == 0);
/* in locking state, any process should not touch this extent. */
EASSERT(ext->oe_state == OES_LOCKING, ext);
EASSERT(ext->oe_owner != NULL, ext);
OSC_EXTENT_DUMP(D_CACHE, ext, "make ready\n");
list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
++page_count;
if (last == NULL || last->oap_obj_off < oap->oap_obj_off)
last = oap;
/* checking ASYNC_READY is race safe */
if ((oap->oap_async_flags & ASYNC_READY) != 0)
continue;
rc = osc_make_ready(env, oap, OBD_BRW_WRITE);
switch (rc) {
case 0:
spin_lock(&oap->oap_lock);
oap->oap_async_flags |= ASYNC_READY;
spin_unlock(&oap->oap_lock);
break;
case -EALREADY:
LASSERT((oap->oap_async_flags & ASYNC_READY) != 0);
break;
default:
LASSERTF(0, "unknown return code: %d\n", rc);
}
}
LASSERT(page_count == ext->oe_nr_pages);
LASSERT(last != NULL);
/* the last page is the only one we need to refresh its count by
* the size of file. */
if (!(last->oap_async_flags & ASYNC_COUNT_STABLE)) {
last->oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE);
LASSERT(last->oap_count > 0);
LASSERT(last->oap_page_off + last->oap_count <= PAGE_CACHE_SIZE);
last->oap_async_flags |= ASYNC_COUNT_STABLE;
}
/* for the rest of pages, we don't need to call osf_refresh_count()
* because it's known they are not the last page */
list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) {
if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) {
oap->oap_count = PAGE_CACHE_SIZE - oap->oap_page_off;
oap->oap_async_flags |= ASYNC_COUNT_STABLE;
}
}
osc_object_lock(obj);
osc_extent_state_set(ext, OES_RPC);
osc_object_unlock(obj);
/* get a refcount for RPC. */
osc_extent_get(ext);
return 0;
}
/**
* Quick and simple version of osc_extent_find(). This function is frequently
* called to expand the extent for the same IO. To expand the extent, the
* page index must be in the same or next chunk of ext->oe_end.
*/
static int osc_extent_expand(struct osc_extent *ext, pgoff_t index, int *grants)
{
struct osc_object *obj = ext->oe_obj;
struct client_obd *cli = osc_cli(obj);
struct osc_extent *next;
int ppc_bits = cli->cl_chunkbits - PAGE_CACHE_SHIFT;
pgoff_t chunk = index >> ppc_bits;
pgoff_t end_chunk;
pgoff_t end_index;
int chunksize = 1 << cli->cl_chunkbits;
int rc = 0;
LASSERT(ext->oe_max_end >= index && ext->oe_start <= index);
osc_object_lock(obj);
LASSERT(sanity_check_nolock(ext) == 0);
end_chunk = ext->oe_end >> ppc_bits;
if (chunk > end_chunk + 1) {
rc = -ERANGE;
goto out;
}
if (end_chunk >= chunk) {
rc = 0;
goto out;
}
LASSERT(end_chunk + 1 == chunk);
/* try to expand this extent to cover @index */
end_index = min(ext->oe_max_end, ((chunk + 1) << ppc_bits) - 1);
next = next_extent(ext);
if (next != NULL && next->oe_start <= end_index) {
/* complex mode - overlapped with the next extent,
* this case will be handled by osc_extent_find() */
rc = -EAGAIN;
goto out;
}
ext->oe_end = end_index;
ext->oe_grants += chunksize;
*grants -= chunksize;
LASSERT(*grants >= 0);
EASSERTF(osc_extent_is_overlapped(obj, ext) == 0, ext,
"overlapped after expanding for %lu.\n", index);
out:
osc_object_unlock(obj);
return rc;
}
static void osc_extent_tree_dump0(int level, struct osc_object *obj,
const char *func, int line)
{
struct osc_extent *ext;
int cnt;
CDEBUG(level, "Dump object %p extents at %s:%d, mppr: %u.\n",
obj, func, line, osc_cli(obj)->cl_max_pages_per_rpc);
/* osc_object_lock(obj); */
cnt = 1;
for (ext = first_extent(obj); ext != NULL; ext = next_extent(ext))
OSC_EXTENT_DUMP(level, ext, "in tree %d.\n", cnt++);
cnt = 1;
list_for_each_entry(ext, &obj->oo_hp_exts, oe_link)
OSC_EXTENT_DUMP(level, ext, "hp %d.\n", cnt++);
cnt = 1;
list_for_each_entry(ext, &obj->oo_urgent_exts, oe_link)
OSC_EXTENT_DUMP(level, ext, "urgent %d.\n", cnt++);
cnt = 1;
list_for_each_entry(ext, &obj->oo_reading_exts, oe_link)
OSC_EXTENT_DUMP(level, ext, "reading %d.\n", cnt++);
/* osc_object_unlock(obj); */
}
/* ------------------ osc extent end ------------------ */
static inline int osc_is_ready(struct osc_object *osc)
{
return !list_empty(&osc->oo_ready_item) ||
!list_empty(&osc->oo_hp_ready_item);
}
#define OSC_IO_DEBUG(OSC, STR, args...) \
CDEBUG(D_CACHE, "obj %p ready %d|%c|%c wr %d|%c|%c rd %d|%c " STR, \
(OSC), osc_is_ready(OSC), \
list_empty_marker(&(OSC)->oo_hp_ready_item), \
list_empty_marker(&(OSC)->oo_ready_item), \
atomic_read(&(OSC)->oo_nr_writes), \
list_empty_marker(&(OSC)->oo_hp_exts), \
list_empty_marker(&(OSC)->oo_urgent_exts), \
atomic_read(&(OSC)->oo_nr_reads), \
list_empty_marker(&(OSC)->oo_reading_exts), \
##args)
static int osc_make_ready(const struct lu_env *env, struct osc_async_page *oap,
int cmd)
{
struct osc_page *opg = oap2osc_page(oap);
struct cl_page *page = cl_page_top(oap2cl_page(oap));
int result;
LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
result = cl_page_make_ready(env, page, CRT_WRITE);
if (result == 0)
opg->ops_submit_time = cfs_time_current();
return result;
}
static int osc_refresh_count(const struct lu_env *env,
struct osc_async_page *oap, int cmd)
{
struct osc_page *opg = oap2osc_page(oap);
struct cl_page *page = oap2cl_page(oap);
struct cl_object *obj;
struct cl_attr *attr = &osc_env_info(env)->oti_attr;
int result;
loff_t kms;
/* readpage queues with _COUNT_STABLE, shouldn't get here. */
LASSERT(!(cmd & OBD_BRW_READ));
LASSERT(opg != NULL);
obj = opg->ops_cl.cpl_obj;
cl_object_attr_lock(obj);
result = cl_object_attr_get(env, obj, attr);
cl_object_attr_unlock(obj);
if (result < 0)
return result;
kms = attr->cat_kms;
if (cl_offset(obj, page->cp_index) >= kms)
/* catch race with truncate */
return 0;
else if (cl_offset(obj, page->cp_index + 1) > kms)
/* catch sub-page write at end of file */
return kms % PAGE_CACHE_SIZE;
else
return PAGE_CACHE_SIZE;
}
static int osc_completion(const struct lu_env *env, struct osc_async_page *oap,
int cmd, int rc)
{
struct osc_page *opg = oap2osc_page(oap);
struct cl_page *page = cl_page_top(oap2cl_page(oap));
struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
enum cl_req_type crt;
int srvlock;
cmd &= ~OBD_BRW_NOQUOTA;
LASSERT(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ));
LASSERT(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE));
LASSERT(opg->ops_transfer_pinned);
/*
* page->cp_req can be NULL if io submission failed before
* cl_req was allocated.
*/
if (page->cp_req != NULL)
cl_req_page_done(env, page);
LASSERT(page->cp_req == NULL);
crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
/* Clear opg->ops_transfer_pinned before VM lock is released. */
opg->ops_transfer_pinned = 0;
spin_lock(&obj->oo_seatbelt);
LASSERT(opg->ops_submitter != NULL);
LASSERT(!list_empty(&opg->ops_inflight));
list_del_init(&opg->ops_inflight);
opg->ops_submitter = NULL;
spin_unlock(&obj->oo_seatbelt);
opg->ops_submit_time = 0;
srvlock = oap->oap_brw_flags & OBD_BRW_SRVLOCK;
/* statistic */
if (rc == 0 && srvlock) {
struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
int bytes = oap->oap_count;
if (crt == CRT_READ)
stats->os_lockless_reads += bytes;
else
stats->os_lockless_writes += bytes;
}
/*
* This has to be the last operation with the page, as locks are
* released in cl_page_completion() and nothing except for the
* reference counter protects page from concurrent reclaim.
*/
lu_ref_del(&page->cp_reference, "transfer", page);
cl_page_completion(env, page, crt, rc);
return 0;
}
#define OSC_DUMP_GRANT(cli, fmt, args...) do { \
struct client_obd *__tmp = (cli); \
CDEBUG(D_CACHE, "%s: { dirty: %ld/%ld dirty_pages: %d/%d " \
"dropped: %ld avail: %ld, reserved: %ld, flight: %d } " fmt, \
__tmp->cl_import->imp_obd->obd_name, \
__tmp->cl_dirty, __tmp->cl_dirty_max, \
atomic_read(&obd_dirty_pages), obd_max_dirty_pages, \
__tmp->cl_lost_grant, __tmp->cl_avail_grant, \
__tmp->cl_reserved_grant, __tmp->cl_w_in_flight, ##args); \
} while (0)
/* caller must hold loi_list_lock */
static void osc_consume_write_grant(struct client_obd *cli,
struct brw_page *pga)
{
assert_spin_locked(&cli->cl_loi_list_lock.lock);
LASSERT(!(pga->flag & OBD_BRW_FROM_GRANT));
atomic_inc(&obd_dirty_pages);
cli->cl_dirty += PAGE_CACHE_SIZE;
pga->flag |= OBD_BRW_FROM_GRANT;
CDEBUG(D_CACHE, "using %lu grant credits for brw %p page %p\n",
PAGE_CACHE_SIZE, pga, pga->pg);
osc_update_next_shrink(cli);
}
/* the companion to osc_consume_write_grant, called when a brw has completed.
* must be called with the loi lock held. */
static void osc_release_write_grant(struct client_obd *cli,
struct brw_page *pga)
{
assert_spin_locked(&cli->cl_loi_list_lock.lock);
if (!(pga->flag & OBD_BRW_FROM_GRANT)) {
return;
}
pga->flag &= ~OBD_BRW_FROM_GRANT;
atomic_dec(&obd_dirty_pages);
cli->cl_dirty -= PAGE_CACHE_SIZE;
if (pga->flag & OBD_BRW_NOCACHE) {
pga->flag &= ~OBD_BRW_NOCACHE;
atomic_dec(&obd_dirty_transit_pages);
cli->cl_dirty_transit -= PAGE_CACHE_SIZE;
}
}
/**
* To avoid sleeping with object lock held, it's good for us allocate enough
* grants before entering into critical section.
*
* client_obd_list_lock held by caller
*/
static int osc_reserve_grant(struct client_obd *cli, unsigned int bytes)
{
int rc = -EDQUOT;
if (cli->cl_avail_grant >= bytes) {
cli->cl_avail_grant -= bytes;
cli->cl_reserved_grant += bytes;
rc = 0;
}
return rc;
}
static void __osc_unreserve_grant(struct client_obd *cli,
unsigned int reserved, unsigned int unused)
{
/* it's quite normal for us to get more grant than reserved.
* Thinking about a case that two extents merged by adding a new
* chunk, we can save one extent tax. If extent tax is greater than
* one chunk, we can save more grant by adding a new chunk */
cli->cl_reserved_grant -= reserved;
if (unused > reserved) {
cli->cl_avail_grant += reserved;
cli->cl_lost_grant += unused - reserved;
} else {
cli->cl_avail_grant += unused;
}
}
void osc_unreserve_grant(struct client_obd *cli,
unsigned int reserved, unsigned int unused)
{
client_obd_list_lock(&cli->cl_loi_list_lock);
__osc_unreserve_grant(cli, reserved, unused);
if (unused > 0)
osc_wake_cache_waiters(cli);
client_obd_list_unlock(&cli->cl_loi_list_lock);
}
/**
* Free grant after IO is finished or canceled.
*
* @lost_grant is used to remember how many grants we have allocated but not
* used, we should return these grants to OST. There're two cases where grants
* can be lost:
* 1. truncate;
* 2. blocksize at OST is less than PAGE_CACHE_SIZE and a partial page was
* written. In this case OST may use less chunks to serve this partial
* write. OSTs don't actually know the page size on the client side. so
* clients have to calculate lost grant by the blocksize on the OST.
* See filter_grant_check() for details.
*/
static void osc_free_grant(struct client_obd *cli, unsigned int nr_pages,
unsigned int lost_grant)
{
int grant = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
client_obd_list_lock(&cli->cl_loi_list_lock);
atomic_sub(nr_pages, &obd_dirty_pages);
cli->cl_dirty -= nr_pages << PAGE_CACHE_SHIFT;
cli->cl_lost_grant += lost_grant;
if (cli->cl_avail_grant < grant && cli->cl_lost_grant >= grant) {
/* borrow some grant from truncate to avoid the case that
* truncate uses up all avail grant */
cli->cl_lost_grant -= grant;
cli->cl_avail_grant += grant;
}
osc_wake_cache_waiters(cli);
client_obd_list_unlock(&cli->cl_loi_list_lock);
CDEBUG(D_CACHE, "lost %u grant: %lu avail: %lu dirty: %lu\n",
lost_grant, cli->cl_lost_grant,
cli->cl_avail_grant, cli->cl_dirty);
}
/**
* The companion to osc_enter_cache(), called when @oap is no longer part of
* the dirty accounting due to error.
*/
static void osc_exit_cache(struct client_obd *cli, struct osc_async_page *oap)
{
client_obd_list_lock(&cli->cl_loi_list_lock);
osc_release_write_grant(cli, &oap->oap_brw_page);
client_obd_list_unlock(&cli->cl_loi_list_lock);
}
/**
* Non-blocking version of osc_enter_cache() that consumes grant only when it
* is available.
*/
static int osc_enter_cache_try(struct client_obd *cli,
struct osc_async_page *oap,
int bytes, int transient)
{
int rc;
OSC_DUMP_GRANT(cli, "need:%d.\n", bytes);
rc = osc_reserve_grant(cli, bytes);
if (rc < 0)
return 0;
if (cli->cl_dirty + PAGE_CACHE_SIZE <= cli->cl_dirty_max &&
atomic_read(&obd_dirty_pages) + 1 <= obd_max_dirty_pages) {
osc_consume_write_grant(cli, &oap->oap_brw_page);
if (transient) {
cli->cl_dirty_transit += PAGE_CACHE_SIZE;
atomic_inc(&obd_dirty_transit_pages);
oap->oap_brw_flags |= OBD_BRW_NOCACHE;
}
rc = 1;
} else {
__osc_unreserve_grant(cli, bytes, bytes);
rc = 0;
}
return rc;
}
static int ocw_granted(struct client_obd *cli, struct osc_cache_waiter *ocw)
{
int rc;
client_obd_list_lock(&cli->cl_loi_list_lock);
rc = list_empty(&ocw->ocw_entry);
client_obd_list_unlock(&cli->cl_loi_list_lock);
return rc;
}
/**
* The main entry to reserve dirty page accounting. Usually the grant reserved
* in this function will be freed in bulk in osc_free_grant() unless it fails
* to add osc cache, in that case, it will be freed in osc_exit_cache().
*
* The process will be put into sleep if it's already run out of grant.
*/
static int osc_enter_cache(const struct lu_env *env, struct client_obd *cli,
struct osc_async_page *oap, int bytes)
{
struct osc_object *osc = oap->oap_obj;
struct lov_oinfo *loi = osc->oo_oinfo;
struct osc_cache_waiter ocw;
struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
int rc = -EDQUOT;
OSC_DUMP_GRANT(cli, "need:%d.\n", bytes);
client_obd_list_lock(&cli->cl_loi_list_lock);
/* force the caller to try sync io. this can jump the list
* of queued writes and create a discontiguous rpc stream */
if (OBD_FAIL_CHECK(OBD_FAIL_OSC_NO_GRANT) ||
cli->cl_dirty_max < PAGE_CACHE_SIZE ||
cli->cl_ar.ar_force_sync || loi->loi_ar.ar_force_sync) {
rc = -EDQUOT;
goto out;
}
/* Hopefully normal case - cache space and write credits available */
if (osc_enter_cache_try(cli, oap, bytes, 0)) {
rc = 0;
goto out;
}
/* We can get here for two reasons: too many dirty pages in cache, or
* run out of grants. In both cases we should write dirty pages out.
* Adding a cache waiter will trigger urgent write-out no matter what
* RPC size will be.
* The exiting condition is no avail grants and no dirty pages caching,
* that really means there is no space on the OST. */
init_waitqueue_head(&ocw.ocw_waitq);
ocw.ocw_oap = oap;
ocw.ocw_grant = bytes;
while (cli->cl_dirty > 0 || cli->cl_w_in_flight > 0) {
list_add_tail(&ocw.ocw_entry, &cli->cl_cache_waiters);
ocw.ocw_rc = 0;
client_obd_list_unlock(&cli->cl_loi_list_lock);
osc_io_unplug_async(env, cli, NULL);
CDEBUG(D_CACHE, "%s: sleeping for cache space @ %p for %p\n",
cli->cl_import->imp_obd->obd_name, &ocw, oap);
rc = l_wait_event(ocw.ocw_waitq, ocw_granted(cli, &ocw), &lwi);
client_obd_list_lock(&cli->cl_loi_list_lock);
/* l_wait_event is interrupted by signal */
if (rc < 0) {
list_del_init(&ocw.ocw_entry);
goto out;
}
LASSERT(list_empty(&ocw.ocw_entry));
rc = ocw.ocw_rc;
if (rc != -EDQUOT)
goto out;
if (osc_enter_cache_try(cli, oap, bytes, 0)) {
rc = 0;
goto out;
}
}
out:
client_obd_list_unlock(&cli->cl_loi_list_lock);
OSC_DUMP_GRANT(cli, "returned %d.\n", rc);
return rc;
}
/* caller must hold loi_list_lock */
void osc_wake_cache_waiters(struct client_obd *cli)
{
struct list_head *l, *tmp;
struct osc_cache_waiter *ocw;
list_for_each_safe(l, tmp, &cli->cl_cache_waiters) {
ocw = list_entry(l, struct osc_cache_waiter, ocw_entry);
list_del_init(&ocw->ocw_entry);
ocw->ocw_rc = -EDQUOT;
/* we can't dirty more */
if ((cli->cl_dirty + PAGE_CACHE_SIZE > cli->cl_dirty_max) ||
(atomic_read(&obd_dirty_pages) + 1 >
obd_max_dirty_pages)) {
CDEBUG(D_CACHE, "no dirty room: dirty: %ld osc max %ld, sys max %d\n",
cli->cl_dirty,
cli->cl_dirty_max, obd_max_dirty_pages);
goto wakeup;
}
ocw->ocw_rc = 0;
if (!osc_enter_cache_try(cli, ocw->ocw_oap, ocw->ocw_grant, 0))
ocw->ocw_rc = -EDQUOT;
wakeup:
CDEBUG(D_CACHE, "wake up %p for oap %p, avail grant %ld, %d\n",
ocw, ocw->ocw_oap, cli->cl_avail_grant, ocw->ocw_rc);
wake_up(&ocw->ocw_waitq);
}
}
static int osc_max_rpc_in_flight(struct client_obd *cli, struct osc_object *osc)
{
int hprpc = !!list_empty(&osc->oo_hp_exts);
return rpcs_in_flight(cli) >= cli->cl_max_rpcs_in_flight + hprpc;
}
/* This maintains the lists of pending pages to read/write for a given object
* (lop). This is used by osc_check_rpcs->osc_next_obj() and osc_list_maint()
* to quickly find objects that are ready to send an RPC. */
static int osc_makes_rpc(struct client_obd *cli, struct osc_object *osc,
int cmd)
{
int invalid_import = 0;
/* if we have an invalid import we want to drain the queued pages
* by forcing them through rpcs that immediately fail and complete
* the pages. recovery relies on this to empty the queued pages
* before canceling the locks and evicting down the llite pages */
if ((cli->cl_import == NULL || cli->cl_import->imp_invalid))
invalid_import = 1;
if (cmd & OBD_BRW_WRITE) {
if (atomic_read(&osc->oo_nr_writes) == 0)
return 0;
if (invalid_import) {
CDEBUG(D_CACHE, "invalid import forcing RPC\n");
return 1;
}
if (!list_empty(&osc->oo_hp_exts)) {
CDEBUG(D_CACHE, "high prio request forcing RPC\n");
return 1;
}
if (!list_empty(&osc->oo_urgent_exts)) {
CDEBUG(D_CACHE, "urgent request forcing RPC\n");
return 1;
}
/* trigger a write rpc stream as long as there are dirtiers
* waiting for space. as they're waiting, they're not going to
* create more pages to coalesce with what's waiting.. */
if (!list_empty(&cli->cl_cache_waiters)) {
CDEBUG(D_CACHE, "cache waiters forcing RPC\n");
return 1;
}
if (atomic_read(&osc->oo_nr_writes) >=
cli->cl_max_pages_per_rpc)
return 1;
} else {
if (atomic_read(&osc->oo_nr_reads) == 0)
return 0;
if (invalid_import) {
CDEBUG(D_CACHE, "invalid import forcing RPC\n");
return 1;
}
/* all read are urgent. */
if (!list_empty(&osc->oo_reading_exts))
return 1;
}
return 0;
}
static void osc_update_pending(struct osc_object *obj, int cmd, int delta)
{
struct client_obd *cli = osc_cli(obj);
if (cmd & OBD_BRW_WRITE) {
atomic_add(delta, &obj->oo_nr_writes);
atomic_add(delta, &cli->cl_pending_w_pages);
LASSERT(atomic_read(&obj->oo_nr_writes) >= 0);
} else {
atomic_add(delta, &obj->oo_nr_reads);
atomic_add(delta, &cli->cl_pending_r_pages);
LASSERT(atomic_read(&obj->oo_nr_reads) >= 0);
}
OSC_IO_DEBUG(obj, "update pending cmd %d delta %d.\n", cmd, delta);
}
static int osc_makes_hprpc(struct osc_object *obj)
{
return !list_empty(&obj->oo_hp_exts);
}
static void on_list(struct list_head *item, struct list_head *list, int should_be_on)
{
if (list_empty(item) && should_be_on)
list_add_tail(item, list);
else if (!list_empty(item) && !should_be_on)
list_del_init(item);
}
/* maintain the osc's cli list membership invariants so that osc_send_oap_rpc
* can find pages to build into rpcs quickly */
static int __osc_list_maint(struct client_obd *cli, struct osc_object *osc)
{
if (osc_makes_hprpc(osc)) {
/* HP rpc */
on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list, 0);
on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 1);
} else {
on_list(&osc->oo_hp_ready_item, &cli->cl_loi_hp_ready_list, 0);
on_list(&osc->oo_ready_item, &cli->cl_loi_ready_list,
osc_makes_rpc(cli, osc, OBD_BRW_WRITE) ||
osc_makes_rpc(cli, osc, OBD_BRW_READ));
}
on_list(&osc->oo_write_item, &cli->cl_loi_write_list,
atomic_read(&osc->oo_nr_writes) > 0);
on_list(&osc->oo_read_item, &cli->cl_loi_read_list,
atomic_read(&osc->oo_nr_reads) > 0);
return osc_is_ready(osc);
}
static int osc_list_maint(struct client_obd *cli, struct osc_object *osc)
{
int is_ready;
client_obd_list_lock(&cli->cl_loi_list_lock);
is_ready = __osc_list_maint(cli, osc);
client_obd_list_unlock(&cli->cl_loi_list_lock);
return is_ready;
}
/* this is trying to propagate async writeback errors back up to the
* application. As an async write fails we record the error code for later if
* the app does an fsync. As long as errors persist we force future rpcs to be
* sync so that the app can get a sync error and break the cycle of queueing
* pages for which writeback will fail. */
static void osc_process_ar(struct osc_async_rc *ar, __u64 xid,
int rc)
{
if (rc) {
if (!ar->ar_rc)
ar->ar_rc = rc;
ar->ar_force_sync = 1;
ar->ar_min_xid = ptlrpc_sample_next_xid();
return;
}
if (ar->ar_force_sync && (xid >= ar->ar_min_xid))
ar->ar_force_sync = 0;
}
/* this must be called holding the loi list lock to give coverage to exit_cache,
* async_flag maintenance, and oap_request */
static void osc_ap_completion(const struct lu_env *env, struct client_obd *cli,
struct osc_async_page *oap, int sent, int rc)
{
struct osc_object *osc = oap->oap_obj;
struct lov_oinfo *loi = osc->oo_oinfo;
__u64 xid = 0;
if (oap->oap_request != NULL) {
xid = ptlrpc_req_xid(oap->oap_request);
ptlrpc_req_finished(oap->oap_request);
oap->oap_request = NULL;
}
/* As the transfer for this page is being done, clear the flags */
spin_lock(&oap->oap_lock);
oap->oap_async_flags = 0;
spin_unlock(&oap->oap_lock);
oap->oap_interrupted = 0;
if (oap->oap_cmd & OBD_BRW_WRITE && xid > 0) {
client_obd_list_lock(&cli->cl_loi_list_lock);
osc_process_ar(&cli->cl_ar, xid, rc);
osc_process_ar(&loi->loi_ar, xid, rc);
client_obd_list_unlock(&cli->cl_loi_list_lock);
}
rc = osc_completion(env, oap, oap->oap_cmd, rc);
if (rc)
CERROR("completion on oap %p obj %p returns %d.\n",
oap, osc, rc);
}
/**
* Try to add extent to one RPC. We need to think about the following things:
* - # of pages must not be over max_pages_per_rpc
* - extent must be compatible with previous ones
*/
static int try_to_add_extent_for_io(struct client_obd *cli,
struct osc_extent *ext, struct list_head *rpclist,
int *pc, unsigned int *max_pages)
{
struct osc_extent *tmp;
struct osc_async_page *oap = list_first_entry(&ext->oe_pages,
struct osc_async_page,
oap_pending_item);
EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE),
ext);
*max_pages = max(ext->oe_mppr, *max_pages);
if (*pc + ext->oe_nr_pages > *max_pages)
return 0;
list_for_each_entry(tmp, rpclist, oe_link) {
struct osc_async_page *oap2;
oap2 = list_first_entry(&tmp->oe_pages, struct osc_async_page,
oap_pending_item);
EASSERT(tmp->oe_owner == current, tmp);
#if 0
if (overlapped(tmp, ext)) {
OSC_EXTENT_DUMP(D_ERROR, tmp, "overlapped %p.\n", ext);
EASSERT(0, ext);
}
#endif
if (oap2cl_page(oap)->cp_type != oap2cl_page(oap2)->cp_type) {
CDEBUG(D_CACHE, "Do not permit different type of IO"
" for a same RPC\n");
return 0;
}
if (tmp->oe_srvlock != ext->oe_srvlock ||
!tmp->oe_grants != !ext->oe_grants)
return 0;
/* remove break for strict check */
break;
}
*pc += ext->oe_nr_pages;
list_move_tail(&ext->oe_link, rpclist);
ext->oe_owner = current;
return 1;
}
/**
* In order to prevent multiple ptlrpcd from breaking contiguous extents,
* get_write_extent() takes all appropriate extents in atomic.
*
* The following policy is used to collect extents for IO:
* 1. Add as many HP extents as possible;
* 2. Add the first urgent extent in urgent extent list and take it out of
* urgent list;
* 3. Add subsequent extents of this urgent extent;
* 4. If urgent list is not empty, goto 2;
* 5. Traverse the extent tree from the 1st extent;
* 6. Above steps exit if there is no space in this RPC.
*/
static int get_write_extents(struct osc_object *obj, struct list_head *rpclist)
{
struct client_obd *cli = osc_cli(obj);
struct osc_extent *ext;
int page_count = 0;
unsigned int max_pages = cli->cl_max_pages_per_rpc;
LASSERT(osc_object_is_locked(obj));
while (!list_empty(&obj->oo_hp_exts)) {
ext = list_entry(obj->oo_hp_exts.next, struct osc_extent,
oe_link);
LASSERT(ext->oe_state == OES_CACHE);
if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
&max_pages))
return page_count;
EASSERT(ext->oe_nr_pages <= max_pages, ext);
}
if (page_count == max_pages)
return page_count;
while (!list_empty(&obj->oo_urgent_exts)) {
ext = list_entry(obj->oo_urgent_exts.next,
struct osc_extent, oe_link);
if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
&max_pages))
return page_count;
if (!ext->oe_intree)
continue;
while ((ext = next_extent(ext)) != NULL) {
if ((ext->oe_state != OES_CACHE) ||
(!list_empty(&ext->oe_link) &&
ext->oe_owner != NULL))
continue;
if (!try_to_add_extent_for_io(cli, ext, rpclist,
&page_count, &max_pages))
return page_count;
}
}
if (page_count == max_pages)
return page_count;
ext = first_extent(obj);
while (ext != NULL) {
if ((ext->oe_state != OES_CACHE) ||
/* this extent may be already in current rpclist */
(!list_empty(&ext->oe_link) && ext->oe_owner != NULL)) {
ext = next_extent(ext);
continue;
}
if (!try_to_add_extent_for_io(cli, ext, rpclist, &page_count,
&max_pages))
return page_count;
ext = next_extent(ext);
}
return page_count;
}
static int
osc_send_write_rpc(const struct lu_env *env, struct client_obd *cli,
struct osc_object *osc, pdl_policy_t pol)
{
LIST_HEAD(rpclist);
struct osc_extent *ext;
struct osc_extent *tmp;
struct osc_extent *first = NULL;
u32 page_count = 0;
int srvlock = 0;
int rc = 0;
LASSERT(osc_object_is_locked(osc));
page_count = get_write_extents(osc, &rpclist);
LASSERT(equi(page_count == 0, list_empty(&rpclist)));
if (list_empty(&rpclist))
return 0;
osc_update_pending(osc, OBD_BRW_WRITE, -page_count);
list_for_each_entry(ext, &rpclist, oe_link) {
LASSERT(ext->oe_state == OES_CACHE ||
ext->oe_state == OES_LOCK_DONE);
if (ext->oe_state == OES_CACHE)
osc_extent_state_set(ext, OES_LOCKING);
else
osc_extent_state_set(ext, OES_RPC);
}
/* we're going to grab page lock, so release object lock because
* lock order is page lock -> object lock. */
osc_object_unlock(osc);
list_for_each_entry_safe(ext, tmp, &rpclist, oe_link) {
if (ext->oe_state == OES_LOCKING) {
rc = osc_extent_make_ready(env, ext);
if (unlikely(rc < 0)) {
list_del_init(&ext->oe_link);
osc_extent_finish(env, ext, 0, rc);
continue;
}
}
if (first == NULL) {
first = ext;
srvlock = ext->oe_srvlock;
} else {
LASSERT(srvlock == ext->oe_srvlock);
}
}
if (!list_empty(&rpclist)) {
LASSERT(page_count > 0);
rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_WRITE, pol);
LASSERT(list_empty(&rpclist));
}
osc_object_lock(osc);
return rc;
}
/**
* prepare pages for ASYNC io and put pages in send queue.
*
* \param cmd OBD_BRW_* macroses
* \param lop pending pages
*
* \return zero if no page added to send queue.
* \return 1 if pages successfully added to send queue.
* \return negative on errors.
*/
static int
osc_send_read_rpc(const struct lu_env *env, struct client_obd *cli,
struct osc_object *osc, pdl_policy_t pol)
{
struct osc_extent *ext;
struct osc_extent *next;
LIST_HEAD(rpclist);
int page_count = 0;
unsigned int max_pages = cli->cl_max_pages_per_rpc;
int rc = 0;
LASSERT(osc_object_is_locked(osc));
list_for_each_entry_safe(ext, next,
&osc->oo_reading_exts, oe_link) {
EASSERT(ext->oe_state == OES_LOCK_DONE, ext);
if (!try_to_add_extent_for_io(cli, ext, &rpclist, &page_count,
&max_pages))
break;
osc_extent_state_set(ext, OES_RPC);
EASSERT(ext->oe_nr_pages <= max_pages, ext);
}
LASSERT(page_count <= max_pages);
osc_update_pending(osc, OBD_BRW_READ, -page_count);
if (!list_empty(&rpclist)) {
osc_object_unlock(osc);
LASSERT(page_count > 0);
rc = osc_build_rpc(env, cli, &rpclist, OBD_BRW_READ, pol);
LASSERT(list_empty(&rpclist));
osc_object_lock(osc);
}
return rc;
}
#define list_to_obj(list, item) ({ \
struct list_head *__tmp = (list)->next; \
list_del_init(__tmp); \
list_entry(__tmp, struct osc_object, oo_##item); \
})
/* This is called by osc_check_rpcs() to find which objects have pages that
* we could be sending. These lists are maintained by osc_makes_rpc(). */
static struct osc_object *osc_next_obj(struct client_obd *cli)
{
/* First return objects that have blocked locks so that they
* will be flushed quickly and other clients can get the lock,
* then objects which have pages ready to be stuffed into RPCs */
if (!list_empty(&cli->cl_loi_hp_ready_list))
return list_to_obj(&cli->cl_loi_hp_ready_list, hp_ready_item);
if (!list_empty(&cli->cl_loi_ready_list))
return list_to_obj(&cli->cl_loi_ready_list, ready_item);
/* then if we have cache waiters, return all objects with queued
* writes. This is especially important when many small files
* have filled up the cache and not been fired into rpcs because
* they don't pass the nr_pending/object threshold */
if (!list_empty(&cli->cl_cache_waiters) &&
!list_empty(&cli->cl_loi_write_list))
return list_to_obj(&cli->cl_loi_write_list, write_item);
/* then return all queued objects when we have an invalid import
* so that they get flushed */
if (cli->cl_import == NULL || cli->cl_import->imp_invalid) {
if (!list_empty(&cli->cl_loi_write_list))
return list_to_obj(&cli->cl_loi_write_list, write_item);
if (!list_empty(&cli->cl_loi_read_list))
return list_to_obj(&cli->cl_loi_read_list, read_item);
}
return NULL;
}
/* called with the loi list lock held */
static void osc_check_rpcs(const struct lu_env *env, struct client_obd *cli,
pdl_policy_t pol)
{
struct osc_object *osc;
int rc = 0;
while ((osc = osc_next_obj(cli)) != NULL) {
struct cl_object *obj = osc2cl(osc);
struct lu_ref_link link;
OSC_IO_DEBUG(osc, "%lu in flight\n", rpcs_in_flight(cli));
if (osc_max_rpc_in_flight(cli, osc)) {
__osc_list_maint(cli, osc);
break;
}
cl_object_get(obj);
client_obd_list_unlock(&cli->cl_loi_list_lock);
lu_object_ref_add_at(&obj->co_lu, &link, "check",
current);
/* attempt some read/write balancing by alternating between
* reads and writes in an object. The makes_rpc checks here
* would be redundant if we were getting read/write work items
* instead of objects. we don't want send_oap_rpc to drain a
* partial read pending queue when we're given this object to
* do io on writes while there are cache waiters */
osc_object_lock(osc);
if (osc_makes_rpc(cli, osc, OBD_BRW_WRITE)) {
rc = osc_send_write_rpc(env, cli, osc, pol);
if (rc < 0) {
CERROR("Write request failed with %d\n", rc);
/* osc_send_write_rpc failed, mostly because of
* memory pressure.
*
* It can't break here, because if:
* - a page was submitted by osc_io_submit, so
* page locked;
* - no request in flight
* - no subsequent request
* The system will be in live-lock state,
* because there is no chance to call
* osc_io_unplug() and osc_check_rpcs() any
* more. pdflush can't help in this case,
* because it might be blocked at grabbing
* the page lock as we mentioned.
*
* Anyway, continue to drain pages. */
/* break; */
}
}
if (osc_makes_rpc(cli, osc, OBD_BRW_READ)) {
rc = osc_send_read_rpc(env, cli, osc, pol);
if (rc < 0)
CERROR("Read request failed with %d\n", rc);
}
osc_object_unlock(osc);
osc_list_maint(cli, osc);
lu_object_ref_del_at(&obj->co_lu, &link, "check",
current);
cl_object_put(env, obj);
client_obd_list_lock(&cli->cl_loi_list_lock);
}
}
static int osc_io_unplug0(const struct lu_env *env, struct client_obd *cli,
struct osc_object *osc, pdl_policy_t pol, int async)
{
int rc = 0;
if (osc != NULL && osc_list_maint(cli, osc) == 0)
return 0;
if (!async) {
/* disable osc_lru_shrink() temporarily to avoid
* potential stack overrun problem. LU-2859 */
atomic_inc(&cli->cl_lru_shrinkers);
client_obd_list_lock(&cli->cl_loi_list_lock);
osc_check_rpcs(env, cli, pol);
client_obd_list_unlock(&cli->cl_loi_list_lock);
atomic_dec(&cli->cl_lru_shrinkers);
} else {
CDEBUG(D_CACHE, "Queue writeback work for client %p.\n", cli);
LASSERT(cli->cl_writeback_work != NULL);
rc = ptlrpcd_queue_work(cli->cl_writeback_work);
}
return rc;
}
static int osc_io_unplug_async(const struct lu_env *env,
struct client_obd *cli, struct osc_object *osc)
{
/* XXX: policy is no use actually. */
return osc_io_unplug0(env, cli, osc, PDL_POLICY_ROUND, 1);
}
void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
struct osc_object *osc, pdl_policy_t pol)
{
(void)osc_io_unplug0(env, cli, osc, pol, 0);
}
int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
struct page *page, loff_t offset)
{
struct obd_export *exp = osc_export(osc);
struct osc_async_page *oap = &ops->ops_oap;
if (!page)
return cfs_size_round(sizeof(*oap));
oap->oap_magic = OAP_MAGIC;
oap->oap_cli = &exp->exp_obd->u.cli;
oap->oap_obj = osc;
oap->oap_page = page;
oap->oap_obj_off = offset;
LASSERT(!(offset & ~CFS_PAGE_MASK));
if (!client_is_remote(exp) && capable(CFS_CAP_SYS_RESOURCE))
oap->oap_brw_flags = OBD_BRW_NOQUOTA;
INIT_LIST_HEAD(&oap->oap_pending_item);
INIT_LIST_HEAD(&oap->oap_rpc_item);
spin_lock_init(&oap->oap_lock);
CDEBUG(D_INFO, "oap %p page %p obj off %llu\n",
oap, page, oap->oap_obj_off);
return 0;
}
int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
struct osc_page *ops)
{
struct osc_io *oio = osc_env_io(env);
struct osc_extent *ext = NULL;
struct osc_async_page *oap = &ops->ops_oap;
struct client_obd *cli = oap->oap_cli;
struct osc_object *osc = oap->oap_obj;
pgoff_t index;
int grants = 0;
int brw_flags = OBD_BRW_ASYNC;
int cmd = OBD_BRW_WRITE;
int need_release = 0;
int rc = 0;
if (oap->oap_magic != OAP_MAGIC)
return -EINVAL;
if (cli->cl_import == NULL || cli->cl_import->imp_invalid)
return -EIO;
if (!list_empty(&oap->oap_pending_item) ||
!list_empty(&oap->oap_rpc_item))
return -EBUSY;
/* Set the OBD_BRW_SRVLOCK before the page is queued. */
brw_flags |= ops->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
if (!client_is_remote(osc_export(osc)) &&
capable(CFS_CAP_SYS_RESOURCE)) {
brw_flags |= OBD_BRW_NOQUOTA;
cmd |= OBD_BRW_NOQUOTA;
}
/* check if the file's owner/group is over quota */
if (!(cmd & OBD_BRW_NOQUOTA)) {
struct cl_object *obj;
struct cl_attr *attr;
unsigned int qid[MAXQUOTAS];
obj = cl_object_top(&osc->oo_cl);
attr = &osc_env_info(env)->oti_attr;
cl_object_attr_lock(obj);
rc = cl_object_attr_get(env, obj, attr);
cl_object_attr_unlock(obj);
qid[USRQUOTA] = attr->cat_uid;
qid[GRPQUOTA] = attr->cat_gid;
if (rc == 0 && osc_quota_chkdq(cli, qid) == NO_QUOTA)
rc = -EDQUOT;
if (rc)
return rc;
}
oap->oap_cmd = cmd;
oap->oap_page_off = ops->ops_from;
oap->oap_count = ops->ops_to - ops->ops_from;
oap->oap_async_flags = 0;
oap->oap_brw_flags = brw_flags;
OSC_IO_DEBUG(osc, "oap %p page %p added for cmd %d\n",
oap, oap->oap_page, oap->oap_cmd & OBD_BRW_RWMASK);
index = oap2cl_page(oap)->cp_index;
/* Add this page into extent by the following steps:
* 1. if there exists an active extent for this IO, mostly this page
* can be added to the active extent and sometimes we need to
* expand extent to accommodate this page;
* 2. otherwise, a new extent will be allocated. */
ext = oio->oi_active;
if (ext != NULL && ext->oe_start <= index && ext->oe_max_end >= index) {
/* one chunk plus extent overhead must be enough to write this
* page */
grants = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
if (ext->oe_end >= index)
grants = 0;
/* it doesn't need any grant to dirty this page */
client_obd_list_lock(&cli->cl_loi_list_lock);
rc = osc_enter_cache_try(cli, oap, grants, 0);
client_obd_list_unlock(&cli->cl_loi_list_lock);
if (rc == 0) { /* try failed */
grants = 0;
need_release = 1;
} else if (ext->oe_end < index) {
int tmp = grants;
/* try to expand this extent */
rc = osc_extent_expand(ext, index, &tmp);
if (rc < 0) {
need_release = 1;
/* don't free reserved grant */
} else {
OSC_EXTENT_DUMP(D_CACHE, ext,
"expanded for %lu.\n", index);
osc_unreserve_grant(cli, grants, tmp);
grants = 0;
}
}
rc = 0;
} else if (ext != NULL) {
/* index is located outside of active extent */
need_release = 1;
}
if (need_release) {
osc_extent_release(env, ext);
oio->oi_active = NULL;
ext = NULL;
}
if (ext == NULL) {
int tmp = (1 << cli->cl_chunkbits) + cli->cl_extent_tax;
/* try to find new extent to cover this page */
LASSERT(oio->oi_active == NULL);
/* we may have allocated grant for this page if we failed
* to expand the previous active extent. */
LASSERT(ergo(grants > 0, grants >= tmp));
rc = 0;
if (grants == 0) {
/* we haven't allocated grant for this page. */
rc = osc_enter_cache(env, cli, oap, tmp);
if (rc == 0)
grants = tmp;
}
tmp = grants;
if (rc == 0) {
ext = osc_extent_find(env, osc, index, &tmp);
if (IS_ERR(ext)) {
LASSERT(tmp == grants);
osc_exit_cache(cli, oap);
rc = PTR_ERR(ext);
ext = NULL;
} else {
oio->oi_active = ext;
}
}
if (grants > 0)
osc_unreserve_grant(cli, grants, tmp);
}
LASSERT(ergo(rc == 0, ext != NULL));
if (ext != NULL) {
EASSERTF(ext->oe_end >= index && ext->oe_start <= index,
ext, "index = %lu.\n", index);
LASSERT((oap->oap_brw_flags & OBD_BRW_FROM_GRANT) != 0);
osc_object_lock(osc);
if (ext->oe_nr_pages == 0)
ext->oe_srvlock = ops->ops_srvlock;
else
LASSERT(ext->oe_srvlock == ops->ops_srvlock);
++ext->oe_nr_pages;
list_add_tail(&oap->oap_pending_item, &ext->oe_pages);
osc_object_unlock(osc);
}
return rc;
}
int osc_teardown_async_page(const struct lu_env *env,
struct osc_object *obj, struct osc_page *ops)
{
struct osc_async_page *oap = &ops->ops_oap;
struct osc_extent *ext = NULL;
int rc = 0;
LASSERT(oap->oap_magic == OAP_MAGIC);
CDEBUG(D_INFO, "teardown oap %p page %p at index %lu.\n",
oap, ops, oap2cl_page(oap)->cp_index);
osc_object_lock(obj);
if (!list_empty(&oap->oap_rpc_item)) {
CDEBUG(D_CACHE, "oap %p is not in cache.\n", oap);
rc = -EBUSY;
} else if (!list_empty(&oap->oap_pending_item)) {
ext = osc_extent_lookup(obj, oap2cl_page(oap)->cp_index);
/* only truncated pages are allowed to be taken out.
* See osc_extent_truncate() and osc_cache_truncate_start()
* for details. */
if (ext != NULL && ext->oe_state != OES_TRUNC) {
OSC_EXTENT_DUMP(D_ERROR, ext, "trunc at %lu.\n",
oap2cl_page(oap)->cp_index);
rc = -EBUSY;
}
}
osc_object_unlock(obj);
if (ext != NULL)
osc_extent_put(env, ext);
return rc;
}
/**
* This is called when a page is picked up by kernel to write out.
*
* We should find out the corresponding extent and add the whole extent
* into urgent list. The extent may be being truncated or used, handle it
* carefully.
*/
int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
struct osc_page *ops)
{
struct osc_extent *ext = NULL;
struct osc_object *obj = cl2osc(ops->ops_cl.cpl_obj);
struct cl_page *cp = ops->ops_cl.cpl_page;
pgoff_t index = cp->cp_index;
struct osc_async_page *oap = &ops->ops_oap;
bool unplug = false;
int rc = 0;
osc_object_lock(obj);
ext = osc_extent_lookup(obj, index);
if (ext == NULL) {
osc_extent_tree_dump(D_ERROR, obj);
LASSERTF(0, "page index %lu is NOT covered.\n", index);
}
switch (ext->oe_state) {
case OES_RPC:
case OES_LOCK_DONE:
CL_PAGE_DEBUG(D_ERROR, env, cl_page_top(cp),
"flush an in-rpc page?\n");
LASSERT(0);
break;
case OES_LOCKING:
/* If we know this extent is being written out, we should abort
* so that the writer can make this page ready. Otherwise, there
* exists a deadlock problem because other process can wait for
* page writeback bit holding page lock; and meanwhile in
* vvp_page_make_ready(), we need to grab page lock before
* really sending the RPC. */
case OES_TRUNC:
/* race with truncate, page will be redirtied */
case OES_ACTIVE:
/* The extent is active so we need to abort and let the caller
* re-dirty the page. If we continued on here, and we were the
* one making the extent active, we could deadlock waiting for
* the page writeback to clear but it won't because the extent
* is active and won't be written out. */
rc = -EAGAIN;
goto out;
default:
break;
}
rc = cl_page_prep(env, io, cl_page_top(cp), CRT_WRITE);
if (rc)
goto out;
spin_lock(&oap->oap_lock);
oap->oap_async_flags |= ASYNC_READY|ASYNC_URGENT;
spin_unlock(&oap->oap_lock);
if (memory_pressure_get())
ext->oe_memalloc = 1;
ext->oe_urgent = 1;
if (ext->oe_state == OES_CACHE) {
OSC_EXTENT_DUMP(D_CACHE, ext,
"flush page %p make it urgent.\n", oap);
if (list_empty(&ext->oe_link))
list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
unplug = true;
}
rc = 0;
out:
osc_object_unlock(obj);
osc_extent_put(env, ext);
if (unplug)
osc_io_unplug_async(env, osc_cli(obj), obj);
return rc;
}
/**
* this is called when a sync waiter receives an interruption. Its job is to
* get the caller woken as soon as possible. If its page hasn't been put in an
* rpc yet it can dequeue immediately. Otherwise it has to mark the rpc as
* desiring interruption which will forcefully complete the rpc once the rpc
* has timed out.
*/
int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops)
{
struct osc_async_page *oap = &ops->ops_oap;
struct osc_object *obj = oap->oap_obj;
struct client_obd *cli = osc_cli(obj);
struct osc_extent *ext;
struct osc_extent *found = NULL;
struct list_head *plist;
pgoff_t index = oap2cl_page(oap)->cp_index;
int rc = -EBUSY;
int cmd;
LASSERT(!oap->oap_interrupted);
oap->oap_interrupted = 1;
/* Find out the caching extent */
osc_object_lock(obj);
if (oap->oap_cmd & OBD_BRW_WRITE) {
plist = &obj->oo_urgent_exts;
cmd = OBD_BRW_WRITE;
} else {
plist = &obj->oo_reading_exts;
cmd = OBD_BRW_READ;
}
list_for_each_entry(ext, plist, oe_link) {
if (ext->oe_start <= index && ext->oe_end >= index) {
LASSERT(ext->oe_state == OES_LOCK_DONE);
/* For OES_LOCK_DONE state extent, it has already held
* a refcount for RPC. */
found = osc_extent_get(ext);
break;
}
}
if (found != NULL) {
list_del_init(&found->oe_link);
osc_update_pending(obj, cmd, -found->oe_nr_pages);
osc_object_unlock(obj);
osc_extent_finish(env, found, 0, -EINTR);
osc_extent_put(env, found);
rc = 0;
} else {
osc_object_unlock(obj);
/* ok, it's been put in an rpc. only one oap gets a request
* reference */
if (oap->oap_request != NULL) {
ptlrpc_mark_interrupted(oap->oap_request);
ptlrpcd_wake(oap->oap_request);
ptlrpc_req_finished(oap->oap_request);
oap->oap_request = NULL;
}
}
osc_list_maint(cli, obj);
return rc;
}
int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
struct list_head *list, int cmd, int brw_flags)
{
struct client_obd *cli = osc_cli(obj);
struct osc_extent *ext;
struct osc_async_page *oap, *tmp;
int page_count = 0;
int mppr = cli->cl_max_pages_per_rpc;
pgoff_t start = CL_PAGE_EOF;
pgoff_t end = 0;
list_for_each_entry(oap, list, oap_pending_item) {
struct cl_page *cp = oap2cl_page(oap);
if (cp->cp_index > end)
end = cp->cp_index;
if (cp->cp_index < start)
start = cp->cp_index;
++page_count;
mppr <<= (page_count > mppr);
}
ext = osc_extent_alloc(obj);
if (ext == NULL) {
list_for_each_entry_safe(oap, tmp, list, oap_pending_item) {
list_del_init(&oap->oap_pending_item);
osc_ap_completion(env, cli, oap, 0, -ENOMEM);
}
return -ENOMEM;
}
ext->oe_rw = !!(cmd & OBD_BRW_READ);
ext->oe_urgent = 1;
ext->oe_start = start;
ext->oe_end = ext->oe_max_end = end;
ext->oe_obj = obj;
ext->oe_srvlock = !!(brw_flags & OBD_BRW_SRVLOCK);
ext->oe_nr_pages = page_count;
ext->oe_mppr = mppr;
list_splice_init(list, &ext->oe_pages);
osc_object_lock(obj);
/* Reuse the initial refcount for RPC, don't drop it */
osc_extent_state_set(ext, OES_LOCK_DONE);
if (cmd & OBD_BRW_WRITE) {
list_add_tail(&ext->oe_link, &obj->oo_urgent_exts);
osc_update_pending(obj, OBD_BRW_WRITE, page_count);
} else {
list_add_tail(&ext->oe_link, &obj->oo_reading_exts);
osc_update_pending(obj, OBD_BRW_READ, page_count);
}
osc_object_unlock(obj);
osc_io_unplug_async(env, cli, obj);
return 0;
}
/**
* Called by osc_io_setattr_start() to freeze and destroy covering extents.
*/
int osc_cache_truncate_start(const struct lu_env *env, struct osc_io *oio,
struct osc_object *obj, __u64 size)
{
struct client_obd *cli = osc_cli(obj);
struct osc_extent *ext;
struct osc_extent *waiting = NULL;
pgoff_t index;
LIST_HEAD(list);
int result = 0;
bool partial;
/* pages with index greater or equal to index will be truncated. */
index = cl_index(osc2cl(obj), size);
partial = size > cl_offset(osc2cl(obj), index);
again:
osc_object_lock(obj);
ext = osc_extent_search(obj, index);
if (ext == NULL)
ext = first_extent(obj);
else if (ext->oe_end < index)
ext = next_extent(ext);
while (ext != NULL) {
EASSERT(ext->oe_state != OES_TRUNC, ext);
if (ext->oe_state > OES_CACHE || ext->oe_urgent) {
/* if ext is in urgent state, it means there must exist
* a page already having been flushed by write_page().
* We have to wait for this extent because we can't
* truncate that page. */
LASSERT(!ext->oe_hp);
OSC_EXTENT_DUMP(D_CACHE, ext,
"waiting for busy extent\n");
waiting = osc_extent_get(ext);
break;
}
OSC_EXTENT_DUMP(D_CACHE, ext, "try to trunc:%llu.\n", size);
osc_extent_get(ext);
if (ext->oe_state == OES_ACTIVE) {
/* though we grab inode mutex for write path, but we
* release it before releasing extent(in osc_io_end()),
* so there is a race window that an extent is still
* in OES_ACTIVE when truncate starts. */
LASSERT(!ext->oe_trunc_pending);
ext->oe_trunc_pending = 1;
} else {
EASSERT(ext->oe_state == OES_CACHE, ext);
osc_extent_state_set(ext, OES_TRUNC);
osc_update_pending(obj, OBD_BRW_WRITE,
-ext->oe_nr_pages);
}
EASSERT(list_empty(&ext->oe_link), ext);
list_add_tail(&ext->oe_link, &list);
ext = next_extent(ext);
}
osc_object_unlock(obj);
osc_list_maint(cli, obj);
while (!list_empty(&list)) {
int rc;
ext = list_entry(list.next, struct osc_extent, oe_link);
list_del_init(&ext->oe_link);
/* extent may be in OES_ACTIVE state because inode mutex
* is released before osc_io_end() in file write case */
if (ext->oe_state != OES_TRUNC)
osc_extent_wait(env, ext, OES_TRUNC);
rc = osc_extent_truncate(ext, index, partial);
if (rc < 0) {
if (result == 0)
result = rc;
OSC_EXTENT_DUMP(D_ERROR, ext,
"truncate error %d\n", rc);
} else if (ext->oe_nr_pages == 0) {
osc_extent_remove(ext);
} else {
/* this must be an overlapped extent which means only
* part of pages in this extent have been truncated.
*/
EASSERTF(ext->oe_start <= index, ext,
"trunc index = %lu/%d.\n", index, partial);
/* fix index to skip this partially truncated extent */
index = ext->oe_end + 1;
partial = false;
/* we need to hold this extent in OES_TRUNC state so
* that no writeback will happen. This is to avoid
* BUG 17397. */
LASSERT(oio->oi_trunc == NULL);
oio->oi_trunc = osc_extent_get(ext);
OSC_EXTENT_DUMP(D_CACHE, ext,
"trunc at %llu\n", size);
}
osc_extent_put(env, ext);
}
if (waiting != NULL) {
int rc;
/* ignore the result of osc_extent_wait the write initiator
* should take care of it. */
rc = osc_extent_wait(env, waiting, OES_INV);
if (rc < 0)
OSC_EXTENT_DUMP(D_CACHE, waiting, "error: %d.\n", rc);
osc_extent_put(env, waiting);
waiting = NULL;
goto again;
}
return result;
}
/**
* Called after osc_io_setattr_end to add oio->oi_trunc back to cache.
*/
void osc_cache_truncate_end(const struct lu_env *env, struct osc_io *oio,
struct osc_object *obj)
{
struct osc_extent *ext = oio->oi_trunc;
oio->oi_trunc = NULL;
if (ext != NULL) {
bool unplug = false;
EASSERT(ext->oe_nr_pages > 0, ext);
EASSERT(ext->oe_state == OES_TRUNC, ext);
EASSERT(!ext->oe_urgent, ext);
OSC_EXTENT_DUMP(D_CACHE, ext, "trunc -> cache.\n");
osc_object_lock(obj);
osc_extent_state_set(ext, OES_CACHE);
if (ext->oe_fsync_wait && !ext->oe_urgent) {
ext->oe_urgent = 1;
list_move_tail(&ext->oe_link, &obj->oo_urgent_exts);
unplug = true;
}
osc_update_pending(obj, OBD_BRW_WRITE, ext->oe_nr_pages);
osc_object_unlock(obj);
osc_extent_put(env, ext);
if (unplug)
osc_io_unplug_async(env, osc_cli(obj), obj);
}
}
/**
* Wait for extents in a specific range to be written out.
* The caller must have called osc_cache_writeback_range() to issue IO
* otherwise it will take a long time for this function to finish.
*
* Caller must hold inode_mutex , or cancel exclusive dlm lock so that
* nobody else can dirty this range of file while we're waiting for
* extents to be written.
*/
int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
pgoff_t start, pgoff_t end)
{
struct osc_extent *ext;
pgoff_t index = start;
int result = 0;
again:
osc_object_lock(obj);
ext = osc_extent_search(obj, index);
if (ext == NULL)
ext = first_extent(obj);
else if (ext->oe_end < index)
ext = next_extent(ext);
while (ext != NULL) {
int rc;
if (ext->oe_start > end)
break;
if (!ext->oe_fsync_wait) {
ext = next_extent(ext);
continue;
}
EASSERT(ergo(ext->oe_state == OES_CACHE,
ext->oe_hp || ext->oe_urgent), ext);
EASSERT(ergo(ext->oe_state == OES_ACTIVE,
!ext->oe_hp && ext->oe_urgent), ext);
index = ext->oe_end + 1;
osc_extent_get(ext);
osc_object_unlock(obj);
rc = osc_extent_wait(env, ext, OES_INV);
if (result == 0)
result = rc;
osc_extent_put(env, ext);
goto again;
}
osc_object_unlock(obj);
OSC_IO_DEBUG(obj, "sync file range.\n");
return result;
}
/**
* Called to write out a range of osc object.
*
* @hp : should be set this is caused by lock cancel;
* @discard: is set if dirty pages should be dropped - file will be deleted or
* truncated, this implies there is no partially discarding extents.
*
* Return how many pages will be issued, or error code if error occurred.
*/
int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
pgoff_t start, pgoff_t end, int hp, int discard)
{
struct osc_extent *ext;
LIST_HEAD(discard_list);
bool unplug = false;
int result = 0;
osc_object_lock(obj);
ext = osc_extent_search(obj, start);
if (ext == NULL)
ext = first_extent(obj);
else if (ext->oe_end < start)
ext = next_extent(ext);
while (ext != NULL) {
if (ext->oe_start > end)
break;
ext->oe_fsync_wait = 1;
switch (ext->oe_state) {
case OES_CACHE:
result += ext->oe_nr_pages;
if (!discard) {
struct list_head *list = NULL;
if (hp) {
EASSERT(!ext->oe_hp, ext);
ext->oe_hp = 1;
list = &obj->oo_hp_exts;
} else if (!ext->oe_urgent) {
ext->oe_urgent = 1;
list = &obj->oo_urgent_exts;
}
if (list != NULL)
list_move_tail(&ext->oe_link, list);
unplug = true;
} else {
/* the only discarder is lock cancelling, so
* [start, end] must contain this extent */
EASSERT(ext->oe_start >= start &&
ext->oe_max_end <= end, ext);
osc_extent_state_set(ext, OES_LOCKING);
ext->oe_owner = current;
list_move_tail(&ext->oe_link,
&discard_list);
osc_update_pending(obj, OBD_BRW_WRITE,
-ext->oe_nr_pages);
}
break;
case OES_ACTIVE:
/* It's pretty bad to wait for ACTIVE extents, because
* we don't know how long we will wait for it to be
* flushed since it may be blocked at awaiting more
* grants. We do this for the correctness of fsync. */
LASSERT(hp == 0 && discard == 0);
ext->oe_urgent = 1;
break;
case OES_TRUNC:
/* this extent is being truncated, can't do anything
* for it now. it will be set to urgent after truncate
* is finished in osc_cache_truncate_end(). */
default:
break;
}
ext = next_extent(ext);
}
osc_object_unlock(obj);
LASSERT(ergo(!discard, list_empty(&discard_list)));
if (!list_empty(&discard_list)) {
struct osc_extent *tmp;
int rc;
osc_list_maint(osc_cli(obj), obj);
list_for_each_entry_safe(ext, tmp, &discard_list, oe_link) {
list_del_init(&ext->oe_link);
EASSERT(ext->oe_state == OES_LOCKING, ext);
/* Discard caching pages. We don't actually write this
* extent out but we complete it as if we did. */
rc = osc_extent_make_ready(env, ext);
if (unlikely(rc < 0)) {
OSC_EXTENT_DUMP(D_ERROR, ext,
"make_ready returned %d\n", rc);
if (result >= 0)
result = rc;
}
/* finish the extent as if the pages were sent */
osc_extent_finish(env, ext, 0, 0);
}
}
if (unplug)
osc_io_unplug(env, osc_cli(obj), obj, PDL_POLICY_ROUND);
if (hp || discard) {
int rc;
rc = osc_cache_wait_range(env, obj, start, end);
if (result >= 0 && rc < 0)
result = rc;
}
OSC_IO_DEBUG(obj, "cache page out.\n");
return result;
}
/** @} osc */