diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/obdclass/cl_page.c')
| -rw-r--r-- | drivers/staging/lustre/lustre/obdclass/cl_page.c | 1046 |
1 files changed, 0 insertions, 1046 deletions
diff --git a/drivers/staging/lustre/lustre/obdclass/cl_page.c b/drivers/staging/lustre/lustre/obdclass/cl_page.c deleted file mode 100644 index d3b25667bc3a..000000000000 --- a/drivers/staging/lustre/lustre/obdclass/cl_page.c +++ /dev/null @@ -1,1046 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * 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.gnu.org/licenses/gpl-2.0.html - * - * GPL HEADER END - */ -/* - * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. - * Use is subject to license terms. - * - * Copyright (c) 2011, 2015, Intel Corporation. - */ -/* - * This file is part of Lustre, http://www.lustre.org/ - * Lustre is a trademark of Sun Microsystems, Inc. - * - * Client Lustre Page. - * - * Author: Nikita Danilov <nikita.danilov@sun.com> - * Author: Jinshan Xiong <jinshan.xiong@intel.com> - */ - -#define DEBUG_SUBSYSTEM S_CLASS - -#include <linux/libcfs/libcfs.h> -#include <obd_class.h> -#include <obd_support.h> -#include <linux/list.h> - -#include <cl_object.h> -#include "cl_internal.h" - -static void cl_page_delete0(const struct lu_env *env, struct cl_page *pg); - -# define PASSERT(env, page, expr) \ - do { \ - if (unlikely(!(expr))) { \ - CL_PAGE_DEBUG(D_ERROR, (env), (page), #expr "\n"); \ - LASSERT(0); \ - } \ - } while (0) - -# define PINVRNT(env, page, exp) \ - ((void)sizeof(env), (void)sizeof(page), (void)sizeof !!(exp)) - -/** - * Internal version of cl_page_get(). - * - * This function can be used to obtain initial reference to previously - * unreferenced cached object. It can be called only if concurrent page - * reclamation is somehow prevented, e.g., by keeping a lock on a VM page, - * associated with \a page. - * - * Use with care! Not exported. - */ -static void cl_page_get_trust(struct cl_page *page) -{ - LASSERT(atomic_read(&page->cp_ref) > 0); - atomic_inc(&page->cp_ref); -} - -/** - * Returns a slice within a page, corresponding to the given layer in the - * device stack. - * - * \see cl_lock_at() - */ -static const struct cl_page_slice * -cl_page_at_trusted(const struct cl_page *page, - const struct lu_device_type *dtype) -{ - const struct cl_page_slice *slice; - - list_for_each_entry(slice, &page->cp_layers, cpl_linkage) { - if (slice->cpl_obj->co_lu.lo_dev->ld_type == dtype) - return slice; - } - return NULL; -} - -static void cl_page_free(const struct lu_env *env, struct cl_page *page) -{ - struct cl_object *obj = page->cp_obj; - - PASSERT(env, page, list_empty(&page->cp_batch)); - PASSERT(env, page, !page->cp_owner); - PASSERT(env, page, page->cp_state == CPS_FREEING); - - while (!list_empty(&page->cp_layers)) { - struct cl_page_slice *slice; - - slice = list_entry(page->cp_layers.next, - struct cl_page_slice, cpl_linkage); - list_del_init(page->cp_layers.next); - if (unlikely(slice->cpl_ops->cpo_fini)) - slice->cpl_ops->cpo_fini(env, slice); - } - lu_object_ref_del_at(&obj->co_lu, &page->cp_obj_ref, "cl_page", page); - cl_object_put(env, obj); - lu_ref_fini(&page->cp_reference); - kfree(page); -} - -/** - * Helper function updating page state. This is the only place in the code - * where cl_page::cp_state field is mutated. - */ -static inline void cl_page_state_set_trust(struct cl_page *page, - enum cl_page_state state) -{ - /* bypass const. */ - *(enum cl_page_state *)&page->cp_state = state; -} - -struct cl_page *cl_page_alloc(const struct lu_env *env, - struct cl_object *o, pgoff_t ind, - struct page *vmpage, - enum cl_page_type type) -{ - struct cl_page *page; - struct lu_object_header *head; - - page = kzalloc(cl_object_header(o)->coh_page_bufsize, GFP_NOFS); - if (page) { - int result = 0; - - atomic_set(&page->cp_ref, 1); - page->cp_obj = o; - cl_object_get(o); - lu_object_ref_add_at(&o->co_lu, &page->cp_obj_ref, "cl_page", - page); - page->cp_vmpage = vmpage; - cl_page_state_set_trust(page, CPS_CACHED); - page->cp_type = type; - INIT_LIST_HEAD(&page->cp_layers); - INIT_LIST_HEAD(&page->cp_batch); - lu_ref_init(&page->cp_reference); - head = o->co_lu.lo_header; - list_for_each_entry(o, &head->loh_layers, co_lu.lo_linkage) { - if (o->co_ops->coo_page_init) { - result = o->co_ops->coo_page_init(env, o, page, - ind); - if (result != 0) { - cl_page_delete0(env, page); - cl_page_free(env, page); - page = ERR_PTR(result); - break; - } - } - } - } else { - page = ERR_PTR(-ENOMEM); - } - return page; -} - -/** - * Returns a cl_page with index \a idx at the object \a o, and associated with - * the VM page \a vmpage. - * - * This is the main entry point into the cl_page caching interface. First, a - * cache (implemented as a per-object radix tree) is consulted. If page is - * found there, it is returned immediately. Otherwise new page is allocated - * and returned. In any case, additional reference to page is acquired. - * - * \see cl_object_find(), cl_lock_find() - */ -struct cl_page *cl_page_find(const struct lu_env *env, - struct cl_object *o, - pgoff_t idx, struct page *vmpage, - enum cl_page_type type) -{ - struct cl_page *page = NULL; - struct cl_object_header *hdr; - - LASSERT(type == CPT_CACHEABLE || type == CPT_TRANSIENT); - might_sleep(); - - hdr = cl_object_header(o); - - CDEBUG(D_PAGE, "%lu@" DFID " %p %lx %d\n", - idx, PFID(&hdr->coh_lu.loh_fid), vmpage, vmpage->private, type); - /* fast path. */ - if (type == CPT_CACHEABLE) { - /* - * vmpage lock is used to protect the child/parent - * relationship - */ - LASSERT(PageLocked(vmpage)); - /* - * cl_vmpage_page() can be called here without any locks as - * - * - "vmpage" is locked (which prevents ->private from - * concurrent updates), and - * - * - "o" cannot be destroyed while current thread holds a - * reference on it. - */ - page = cl_vmpage_page(vmpage, o); - - if (page) - return page; - } - - /* allocate and initialize cl_page */ - page = cl_page_alloc(env, o, idx, vmpage, type); - return page; -} -EXPORT_SYMBOL(cl_page_find); - -static inline int cl_page_invariant(const struct cl_page *pg) -{ - return cl_page_in_use_noref(pg); -} - -static void cl_page_state_set0(const struct lu_env *env, - struct cl_page *page, enum cl_page_state state) -{ - enum cl_page_state old; - - /* - * Matrix of allowed state transitions [old][new], for sanity - * checking. - */ - static const int allowed_transitions[CPS_NR][CPS_NR] = { - [CPS_CACHED] = { - [CPS_CACHED] = 0, - [CPS_OWNED] = 1, /* io finds existing cached page */ - [CPS_PAGEIN] = 0, - [CPS_PAGEOUT] = 1, /* write-out from the cache */ - [CPS_FREEING] = 1, /* eviction on the memory pressure */ - }, - [CPS_OWNED] = { - [CPS_CACHED] = 1, /* release to the cache */ - [CPS_OWNED] = 0, - [CPS_PAGEIN] = 1, /* start read immediately */ - [CPS_PAGEOUT] = 1, /* start write immediately */ - [CPS_FREEING] = 1, /* lock invalidation or truncate */ - }, - [CPS_PAGEIN] = { - [CPS_CACHED] = 1, /* io completion */ - [CPS_OWNED] = 0, - [CPS_PAGEIN] = 0, - [CPS_PAGEOUT] = 0, - [CPS_FREEING] = 0, - }, - [CPS_PAGEOUT] = { - [CPS_CACHED] = 1, /* io completion */ - [CPS_OWNED] = 0, - [CPS_PAGEIN] = 0, - [CPS_PAGEOUT] = 0, - [CPS_FREEING] = 0, - }, - [CPS_FREEING] = { - [CPS_CACHED] = 0, - [CPS_OWNED] = 0, - [CPS_PAGEIN] = 0, - [CPS_PAGEOUT] = 0, - [CPS_FREEING] = 0, - } - }; - - old = page->cp_state; - PASSERT(env, page, allowed_transitions[old][state]); - CL_PAGE_HEADER(D_TRACE, env, page, "%d -> %d\n", old, state); - PASSERT(env, page, page->cp_state == old); - PASSERT(env, page, equi(state == CPS_OWNED, page->cp_owner)); - cl_page_state_set_trust(page, state); -} - -static void cl_page_state_set(const struct lu_env *env, - struct cl_page *page, enum cl_page_state state) -{ - cl_page_state_set0(env, page, state); -} - -/** - * Acquires an additional reference to a page. - * - * This can be called only by caller already possessing a reference to \a - * page. - * - * \see cl_object_get(), cl_lock_get(). - */ -void cl_page_get(struct cl_page *page) -{ - cl_page_get_trust(page); -} -EXPORT_SYMBOL(cl_page_get); - -/** - * Releases a reference to a page. - * - * When last reference is released, page is returned to the cache, unless it - * is in cl_page_state::CPS_FREEING state, in which case it is immediately - * destroyed. - * - * \see cl_object_put(), cl_lock_put(). - */ -void cl_page_put(const struct lu_env *env, struct cl_page *page) -{ - CL_PAGE_HEADER(D_TRACE, env, page, "%d\n", - atomic_read(&page->cp_ref)); - - if (atomic_dec_and_test(&page->cp_ref)) { - LASSERT(page->cp_state == CPS_FREEING); - - LASSERT(atomic_read(&page->cp_ref) == 0); - PASSERT(env, page, !page->cp_owner); - PASSERT(env, page, list_empty(&page->cp_batch)); - /* - * Page is no longer reachable by other threads. Tear - * it down. - */ - cl_page_free(env, page); - } -} -EXPORT_SYMBOL(cl_page_put); - -/** - * Returns a cl_page associated with a VM page, and given cl_object. - */ -struct cl_page *cl_vmpage_page(struct page *vmpage, struct cl_object *obj) -{ - struct cl_page *page; - - LASSERT(PageLocked(vmpage)); - - /* - * NOTE: absence of races and liveness of data are guaranteed by page - * lock on a "vmpage". That works because object destruction has - * bottom-to-top pass. - */ - - page = (struct cl_page *)vmpage->private; - if (page) { - cl_page_get_trust(page); - LASSERT(page->cp_type == CPT_CACHEABLE); - } - return page; -} -EXPORT_SYMBOL(cl_vmpage_page); - -const struct cl_page_slice *cl_page_at(const struct cl_page *page, - const struct lu_device_type *dtype) -{ - return cl_page_at_trusted(page, dtype); -} -EXPORT_SYMBOL(cl_page_at); - -#define CL_PAGE_OP(opname) offsetof(struct cl_page_operations, opname) - -#define CL_PAGE_INVOKE(_env, _page, _op, _proto, ...) \ -({ \ - const struct lu_env *__env = (_env); \ - struct cl_page *__page = (_page); \ - const struct cl_page_slice *__scan; \ - int __result; \ - ptrdiff_t __op = (_op); \ - int (*__method)_proto; \ - \ - __result = 0; \ - list_for_each_entry(__scan, &__page->cp_layers, cpl_linkage) { \ - __method = *(void **)((char *)__scan->cpl_ops + __op); \ - if (__method) { \ - __result = (*__method)(__env, __scan, ## __VA_ARGS__); \ - if (__result != 0) \ - break; \ - } \ - } \ - if (__result > 0) \ - __result = 0; \ - __result; \ -}) - -#define CL_PAGE_INVOID(_env, _page, _op, _proto, ...) \ -do { \ - const struct lu_env *__env = (_env); \ - struct cl_page *__page = (_page); \ - const struct cl_page_slice *__scan; \ - ptrdiff_t __op = (_op); \ - void (*__method)_proto; \ - \ - list_for_each_entry(__scan, &__page->cp_layers, cpl_linkage) { \ - __method = *(void **)((char *)__scan->cpl_ops + __op); \ - if (__method) \ - (*__method)(__env, __scan, ## __VA_ARGS__); \ - } \ -} while (0) - -#define CL_PAGE_INVOID_REVERSE(_env, _page, _op, _proto, ...) \ -do { \ - const struct lu_env *__env = (_env); \ - struct cl_page *__page = (_page); \ - const struct cl_page_slice *__scan; \ - ptrdiff_t __op = (_op); \ - void (*__method)_proto; \ - \ - list_for_each_entry_reverse(__scan, &__page->cp_layers, cpl_linkage) { \ - __method = *(void **)((char *)__scan->cpl_ops + __op); \ - if (__method) \ - (*__method)(__env, __scan, ## __VA_ARGS__); \ - } \ -} while (0) - -static int cl_page_invoke(const struct lu_env *env, - struct cl_io *io, struct cl_page *page, ptrdiff_t op) - -{ - PINVRNT(env, page, cl_object_same(page->cp_obj, io->ci_obj)); - return CL_PAGE_INVOKE(env, page, op, - (const struct lu_env *, - const struct cl_page_slice *, struct cl_io *), - io); -} - -static void cl_page_invoid(const struct lu_env *env, - struct cl_io *io, struct cl_page *page, ptrdiff_t op) - -{ - PINVRNT(env, page, cl_object_same(page->cp_obj, io->ci_obj)); - CL_PAGE_INVOID(env, page, op, - (const struct lu_env *, - const struct cl_page_slice *, struct cl_io *), io); -} - -static void cl_page_owner_clear(struct cl_page *page) -{ - if (page->cp_owner) { - LASSERT(page->cp_owner->ci_owned_nr > 0); - page->cp_owner->ci_owned_nr--; - page->cp_owner = NULL; - } -} - -static void cl_page_owner_set(struct cl_page *page) -{ - page->cp_owner->ci_owned_nr++; -} - -void cl_page_disown0(const struct lu_env *env, - struct cl_io *io, struct cl_page *pg) -{ - enum cl_page_state state; - - state = pg->cp_state; - PINVRNT(env, pg, state == CPS_OWNED || state == CPS_FREEING); - PINVRNT(env, pg, cl_page_invariant(pg) || state == CPS_FREEING); - cl_page_owner_clear(pg); - - if (state == CPS_OWNED) - cl_page_state_set(env, pg, CPS_CACHED); - /* - * Completion call-backs are executed in the bottom-up order, so that - * uppermost layer (llite), responsible for VFS/VM interaction runs - * last and can release locks safely. - */ - CL_PAGE_INVOID_REVERSE(env, pg, CL_PAGE_OP(cpo_disown), - (const struct lu_env *, - const struct cl_page_slice *, struct cl_io *), - io); -} - -/** - * returns true, iff page is owned by the given io. - */ -int cl_page_is_owned(const struct cl_page *pg, const struct cl_io *io) -{ - struct cl_io *top = cl_io_top((struct cl_io *)io); - - LINVRNT(cl_object_same(pg->cp_obj, io->ci_obj)); - return pg->cp_state == CPS_OWNED && pg->cp_owner == top; -} -EXPORT_SYMBOL(cl_page_is_owned); - -/** - * Try to own a page by IO. - * - * Waits until page is in cl_page_state::CPS_CACHED state, and then switch it - * into cl_page_state::CPS_OWNED state. - * - * \pre !cl_page_is_owned(pg, io) - * \post result == 0 iff cl_page_is_owned(pg, io) - * - * \retval 0 success - * - * \retval -ve failure, e.g., page was destroyed (and landed in - * cl_page_state::CPS_FREEING instead of cl_page_state::CPS_CACHED). - * or, page was owned by another thread, or in IO. - * - * \see cl_page_disown() - * \see cl_page_operations::cpo_own() - * \see cl_page_own_try() - * \see cl_page_own - */ -static int cl_page_own0(const struct lu_env *env, struct cl_io *io, - struct cl_page *pg, int nonblock) -{ - int result; - - PINVRNT(env, pg, !cl_page_is_owned(pg, io)); - - io = cl_io_top(io); - - if (pg->cp_state == CPS_FREEING) { - result = -ENOENT; - } else { - result = CL_PAGE_INVOKE(env, pg, CL_PAGE_OP(cpo_own), - (const struct lu_env *, - const struct cl_page_slice *, - struct cl_io *, int), - io, nonblock); - if (result == 0) { - PASSERT(env, pg, !pg->cp_owner); - pg->cp_owner = cl_io_top(io); - cl_page_owner_set(pg); - if (pg->cp_state != CPS_FREEING) { - cl_page_state_set(env, pg, CPS_OWNED); - } else { - cl_page_disown0(env, io, pg); - result = -ENOENT; - } - } - } - PINVRNT(env, pg, ergo(result == 0, cl_page_invariant(pg))); - return result; -} - -/** - * Own a page, might be blocked. - * - * \see cl_page_own0() - */ -int cl_page_own(const struct lu_env *env, struct cl_io *io, struct cl_page *pg) -{ - return cl_page_own0(env, io, pg, 0); -} -EXPORT_SYMBOL(cl_page_own); - -/** - * Nonblock version of cl_page_own(). - * - * \see cl_page_own0() - */ -int cl_page_own_try(const struct lu_env *env, struct cl_io *io, - struct cl_page *pg) -{ - return cl_page_own0(env, io, pg, 1); -} -EXPORT_SYMBOL(cl_page_own_try); - -/** - * Assume page ownership. - * - * Called when page is already locked by the hosting VM. - * - * \pre !cl_page_is_owned(pg, io) - * \post cl_page_is_owned(pg, io) - * - * \see cl_page_operations::cpo_assume() - */ -void cl_page_assume(const struct lu_env *env, - struct cl_io *io, struct cl_page *pg) -{ - PINVRNT(env, pg, cl_object_same(pg->cp_obj, io->ci_obj)); - - io = cl_io_top(io); - - cl_page_invoid(env, io, pg, CL_PAGE_OP(cpo_assume)); - PASSERT(env, pg, !pg->cp_owner); - pg->cp_owner = cl_io_top(io); - cl_page_owner_set(pg); - cl_page_state_set(env, pg, CPS_OWNED); -} -EXPORT_SYMBOL(cl_page_assume); - -/** - * Releases page ownership without unlocking the page. - * - * Moves page into cl_page_state::CPS_CACHED without releasing a lock on the - * underlying VM page (as VM is supposed to do this itself). - * - * \pre cl_page_is_owned(pg, io) - * \post !cl_page_is_owned(pg, io) - * - * \see cl_page_assume() - */ -void cl_page_unassume(const struct lu_env *env, - struct cl_io *io, struct cl_page *pg) -{ - PINVRNT(env, pg, cl_page_is_owned(pg, io)); - PINVRNT(env, pg, cl_page_invariant(pg)); - - io = cl_io_top(io); - cl_page_owner_clear(pg); - cl_page_state_set(env, pg, CPS_CACHED); - CL_PAGE_INVOID_REVERSE(env, pg, CL_PAGE_OP(cpo_unassume), - (const struct lu_env *, - const struct cl_page_slice *, struct cl_io *), - io); -} -EXPORT_SYMBOL(cl_page_unassume); - -/** - * Releases page ownership. - * - * Moves page into cl_page_state::CPS_CACHED. - * - * \pre cl_page_is_owned(pg, io) - * \post !cl_page_is_owned(pg, io) - * - * \see cl_page_own() - * \see cl_page_operations::cpo_disown() - */ -void cl_page_disown(const struct lu_env *env, - struct cl_io *io, struct cl_page *pg) -{ - PINVRNT(env, pg, cl_page_is_owned(pg, io) || - pg->cp_state == CPS_FREEING); - - io = cl_io_top(io); - cl_page_disown0(env, io, pg); -} -EXPORT_SYMBOL(cl_page_disown); - -/** - * Called when page is to be removed from the object, e.g., as a result of - * truncate. - * - * Calls cl_page_operations::cpo_discard() top-to-bottom. - * - * \pre cl_page_is_owned(pg, io) - * - * \see cl_page_operations::cpo_discard() - */ -void cl_page_discard(const struct lu_env *env, - struct cl_io *io, struct cl_page *pg) -{ - PINVRNT(env, pg, cl_page_is_owned(pg, io)); - PINVRNT(env, pg, cl_page_invariant(pg)); - - cl_page_invoid(env, io, pg, CL_PAGE_OP(cpo_discard)); -} -EXPORT_SYMBOL(cl_page_discard); - -/** - * Version of cl_page_delete() that can be called for not fully constructed - * pages, e.g,. in a error handling cl_page_find()->cl_page_delete0() - * path. Doesn't check page invariant. - */ -static void cl_page_delete0(const struct lu_env *env, struct cl_page *pg) -{ - PASSERT(env, pg, pg->cp_state != CPS_FREEING); - - /* - * Sever all ways to obtain new pointers to @pg. - */ - cl_page_owner_clear(pg); - - cl_page_state_set0(env, pg, CPS_FREEING); - - CL_PAGE_INVOID_REVERSE(env, pg, CL_PAGE_OP(cpo_delete), - (const struct lu_env *, - const struct cl_page_slice *)); -} - -/** - * Called when a decision is made to throw page out of memory. - * - * Notifies all layers about page destruction by calling - * cl_page_operations::cpo_delete() method top-to-bottom. - * - * Moves page into cl_page_state::CPS_FREEING state (this is the only place - * where transition to this state happens). - * - * Eliminates all venues through which new references to the page can be - * obtained: - * - * - removes page from the radix trees, - * - * - breaks linkage from VM page to cl_page. - * - * Once page reaches cl_page_state::CPS_FREEING, all remaining references will - * drain after some time, at which point page will be recycled. - * - * \pre VM page is locked - * \post pg->cp_state == CPS_FREEING - * - * \see cl_page_operations::cpo_delete() - */ -void cl_page_delete(const struct lu_env *env, struct cl_page *pg) -{ - PINVRNT(env, pg, cl_page_invariant(pg)); - cl_page_delete0(env, pg); -} -EXPORT_SYMBOL(cl_page_delete); - -/** - * Marks page up-to-date. - * - * Call cl_page_operations::cpo_export() through all layers top-to-bottom. The - * layer responsible for VM interaction has to mark/clear page as up-to-date - * by the \a uptodate argument. - * - * \see cl_page_operations::cpo_export() - */ -void cl_page_export(const struct lu_env *env, struct cl_page *pg, int uptodate) -{ - PINVRNT(env, pg, cl_page_invariant(pg)); - CL_PAGE_INVOID(env, pg, CL_PAGE_OP(cpo_export), - (const struct lu_env *, - const struct cl_page_slice *, int), uptodate); -} -EXPORT_SYMBOL(cl_page_export); - -/** - * Returns true, iff \a pg is VM locked in a suitable sense by the calling - * thread. - */ -int cl_page_is_vmlocked(const struct lu_env *env, const struct cl_page *pg) -{ - int result; - const struct cl_page_slice *slice; - - slice = container_of(pg->cp_layers.next, - const struct cl_page_slice, cpl_linkage); - PASSERT(env, pg, slice->cpl_ops->cpo_is_vmlocked); - /* - * Call ->cpo_is_vmlocked() directly instead of going through - * CL_PAGE_INVOKE(), because cl_page_is_vmlocked() is used by - * cl_page_invariant(). - */ - result = slice->cpl_ops->cpo_is_vmlocked(env, slice); - PASSERT(env, pg, result == -EBUSY || result == -ENODATA); - return result == -EBUSY; -} -EXPORT_SYMBOL(cl_page_is_vmlocked); - -static enum cl_page_state cl_req_type_state(enum cl_req_type crt) -{ - return crt == CRT_WRITE ? CPS_PAGEOUT : CPS_PAGEIN; -} - -static void cl_page_io_start(const struct lu_env *env, - struct cl_page *pg, enum cl_req_type crt) -{ - /* - * Page is queued for IO, change its state. - */ - cl_page_owner_clear(pg); - cl_page_state_set(env, pg, cl_req_type_state(crt)); -} - -/** - * Prepares page for immediate transfer. cl_page_operations::cpo_prep() is - * called top-to-bottom. Every layer either agrees to submit this page (by - * returning 0), or requests to omit this page (by returning -EALREADY). Layer - * handling interactions with the VM also has to inform VM that page is under - * transfer now. - */ -int cl_page_prep(const struct lu_env *env, struct cl_io *io, - struct cl_page *pg, enum cl_req_type crt) -{ - int result; - - PINVRNT(env, pg, cl_page_is_owned(pg, io)); - PINVRNT(env, pg, cl_page_invariant(pg)); - PINVRNT(env, pg, crt < CRT_NR); - - /* - * XXX this has to be called bottom-to-top, so that llite can set up - * PG_writeback without risking other layers deciding to skip this - * page. - */ - if (crt >= CRT_NR) - return -EINVAL; - result = cl_page_invoke(env, io, pg, CL_PAGE_OP(io[crt].cpo_prep)); - if (result == 0) - cl_page_io_start(env, pg, crt); - - CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, result); - return result; -} -EXPORT_SYMBOL(cl_page_prep); - -/** - * Notify layers about transfer completion. - * - * Invoked by transfer sub-system (which is a part of osc) to notify layers - * that a transfer, of which this page is a part of has completed. - * - * Completion call-backs are executed in the bottom-up order, so that - * uppermost layer (llite), responsible for the VFS/VM interaction runs last - * and can release locks safely. - * - * \pre pg->cp_state == CPS_PAGEIN || pg->cp_state == CPS_PAGEOUT - * \post pg->cp_state == CPS_CACHED - * - * \see cl_page_operations::cpo_completion() - */ -void cl_page_completion(const struct lu_env *env, - struct cl_page *pg, enum cl_req_type crt, int ioret) -{ - struct cl_sync_io *anchor = pg->cp_sync_io; - - PASSERT(env, pg, crt < CRT_NR); - PASSERT(env, pg, pg->cp_state == cl_req_type_state(crt)); - - CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, ioret); - - cl_page_state_set(env, pg, CPS_CACHED); - if (crt >= CRT_NR) - return; - CL_PAGE_INVOID_REVERSE(env, pg, CL_PAGE_OP(io[crt].cpo_completion), - (const struct lu_env *, - const struct cl_page_slice *, int), ioret); - if (anchor) { - LASSERT(pg->cp_sync_io == anchor); - pg->cp_sync_io = NULL; - cl_sync_io_note(env, anchor, ioret); - } -} -EXPORT_SYMBOL(cl_page_completion); - -/** - * Notify layers that transfer formation engine decided to yank this page from - * the cache and to make it a part of a transfer. - * - * \pre pg->cp_state == CPS_CACHED - * \post pg->cp_state == CPS_PAGEIN || pg->cp_state == CPS_PAGEOUT - * - * \see cl_page_operations::cpo_make_ready() - */ -int cl_page_make_ready(const struct lu_env *env, struct cl_page *pg, - enum cl_req_type crt) -{ - int result; - - PINVRNT(env, pg, crt < CRT_NR); - - if (crt >= CRT_NR) - return -EINVAL; - result = CL_PAGE_INVOKE(env, pg, CL_PAGE_OP(io[crt].cpo_make_ready), - (const struct lu_env *, - const struct cl_page_slice *)); - if (result == 0) { - PASSERT(env, pg, pg->cp_state == CPS_CACHED); - cl_page_io_start(env, pg, crt); - } - CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, result); - return result; -} -EXPORT_SYMBOL(cl_page_make_ready); - -/** - * Called if a pge is being written back by kernel's intention. - * - * \pre cl_page_is_owned(pg, io) - * \post ergo(result == 0, pg->cp_state == CPS_PAGEOUT) - * - * \see cl_page_operations::cpo_flush() - */ -int cl_page_flush(const struct lu_env *env, struct cl_io *io, - struct cl_page *pg) -{ - int result; - - PINVRNT(env, pg, cl_page_is_owned(pg, io)); - PINVRNT(env, pg, cl_page_invariant(pg)); - - result = cl_page_invoke(env, io, pg, CL_PAGE_OP(cpo_flush)); - - CL_PAGE_HEADER(D_TRACE, env, pg, "%d\n", result); - return result; -} -EXPORT_SYMBOL(cl_page_flush); - -/** - * Tells transfer engine that only part of a page is to be transmitted. - * - * \see cl_page_operations::cpo_clip() - */ -void cl_page_clip(const struct lu_env *env, struct cl_page *pg, - int from, int to) -{ - PINVRNT(env, pg, cl_page_invariant(pg)); - - CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", from, to); - CL_PAGE_INVOID(env, pg, CL_PAGE_OP(cpo_clip), - (const struct lu_env *, - const struct cl_page_slice *, int, int), - from, to); -} -EXPORT_SYMBOL(cl_page_clip); - -/** - * Prints human readable representation of \a pg to the \a f. - */ -void cl_page_header_print(const struct lu_env *env, void *cookie, - lu_printer_t printer, const struct cl_page *pg) -{ - (*printer)(env, cookie, - "page@%p[%d %p %d %d %p]\n", - pg, atomic_read(&pg->cp_ref), pg->cp_obj, - pg->cp_state, pg->cp_type, - pg->cp_owner); -} -EXPORT_SYMBOL(cl_page_header_print); - -/** - * Prints human readable representation of \a pg to the \a f. - */ -void cl_page_print(const struct lu_env *env, void *cookie, - lu_printer_t printer, const struct cl_page *pg) -{ - cl_page_header_print(env, cookie, printer, pg); - CL_PAGE_INVOKE(env, (struct cl_page *)pg, CL_PAGE_OP(cpo_print), - (const struct lu_env *env, - const struct cl_page_slice *slice, - void *cookie, lu_printer_t p), cookie, printer); - (*printer)(env, cookie, "end page@%p\n", pg); -} -EXPORT_SYMBOL(cl_page_print); - -/** - * Cancel a page which is still in a transfer. - */ -int cl_page_cancel(const struct lu_env *env, struct cl_page *page) -{ - return CL_PAGE_INVOKE(env, page, CL_PAGE_OP(cpo_cancel), - (const struct lu_env *, - const struct cl_page_slice *)); -} - -/** - * Converts a byte offset within object \a obj into a page index. - */ -loff_t cl_offset(const struct cl_object *obj, pgoff_t idx) -{ - /* - * XXX for now. - */ - return (loff_t)idx << PAGE_SHIFT; -} -EXPORT_SYMBOL(cl_offset); - -/** - * Converts a page index into a byte offset within object \a obj. - */ -pgoff_t cl_index(const struct cl_object *obj, loff_t offset) -{ - /* - * XXX for now. - */ - return offset >> PAGE_SHIFT; -} -EXPORT_SYMBOL(cl_index); - -size_t cl_page_size(const struct cl_object *obj) -{ - return 1UL << PAGE_SHIFT; -} -EXPORT_SYMBOL(cl_page_size); - -/** - * Adds page slice to the compound page. - * - * This is called by cl_object_operations::coo_page_init() methods to add a - * per-layer state to the page. New state is added at the end of - * cl_page::cp_layers list, that is, it is at the bottom of the stack. - * - * \see cl_lock_slice_add(), cl_req_slice_add(), cl_io_slice_add() - */ -void cl_page_slice_add(struct cl_page *page, struct cl_page_slice *slice, - struct cl_object *obj, pgoff_t index, - const struct cl_page_operations *ops) -{ - list_add_tail(&slice->cpl_linkage, &page->cp_layers); - slice->cpl_obj = obj; - slice->cpl_index = index; - slice->cpl_ops = ops; - slice->cpl_page = page; -} -EXPORT_SYMBOL(cl_page_slice_add); - -/** - * Allocate and initialize cl_cache, called by ll_init_sbi(). - */ -struct cl_client_cache *cl_cache_init(unsigned long lru_page_max) -{ - struct cl_client_cache *cache = NULL; - - cache = kzalloc(sizeof(*cache), GFP_KERNEL); - if (!cache) - return NULL; - - /* Initialize cache data */ - atomic_set(&cache->ccc_users, 1); - cache->ccc_lru_max = lru_page_max; - atomic_long_set(&cache->ccc_lru_left, lru_page_max); - spin_lock_init(&cache->ccc_lru_lock); - INIT_LIST_HEAD(&cache->ccc_lru); - - atomic_long_set(&cache->ccc_unstable_nr, 0); - init_waitqueue_head(&cache->ccc_unstable_waitq); - - return cache; -} -EXPORT_SYMBOL(cl_cache_init); - -/** - * Increase cl_cache refcount - */ -void cl_cache_incref(struct cl_client_cache *cache) -{ - atomic_inc(&cache->ccc_users); -} -EXPORT_SYMBOL(cl_cache_incref); - -/** - * Decrease cl_cache refcount and free the cache if refcount=0. - * Since llite, lov and osc all hold cl_cache refcount, - * the free will not cause race. (LU-6173) - */ -void cl_cache_decref(struct cl_client_cache *cache) -{ - if (atomic_dec_and_test(&cache->ccc_users)) - kfree(cache); -} -EXPORT_SYMBOL(cl_cache_decref); |