diff options
Diffstat (limited to 'drivers/staging/lustre/lnet/lnet/lib-md.c')
| -rw-r--r-- | drivers/staging/lustre/lnet/lnet/lib-md.c | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lnet/lnet/lib-md.c b/drivers/staging/lustre/lnet/lnet/lib-md.c new file mode 100644 index 000000000000..ae643f26933b --- /dev/null +++ b/drivers/staging/lustre/lnet/lnet/lib-md.c @@ -0,0 +1,451 @@ +/* + * 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) 2003, 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. + * + * lnet/lnet/lib-md.c + * + * Memory Descriptor management routines + */ + +#define DEBUG_SUBSYSTEM S_LNET + +#include <linux/lnet/lib-lnet.h> + +/* must be called with lnet_res_lock held */ +void +lnet_md_unlink(lnet_libmd_t *md) +{ + if ((md->md_flags & LNET_MD_FLAG_ZOMBIE) == 0) { + /* first unlink attempt... */ + lnet_me_t *me = md->md_me; + + md->md_flags |= LNET_MD_FLAG_ZOMBIE; + + /* Disassociate from ME (if any), and unlink it if it was created + * with LNET_UNLINK */ + if (me != NULL) { + /* detach MD from portal */ + lnet_ptl_detach_md(me, md); + if (me->me_unlink == LNET_UNLINK) + lnet_me_unlink(me); + } + + /* ensure all future handle lookups fail */ + lnet_res_lh_invalidate(&md->md_lh); + } + + if (md->md_refcount != 0) { + CDEBUG(D_NET, "Queueing unlink of md %p\n", md); + return; + } + + CDEBUG(D_NET, "Unlinking md %p\n", md); + + if (md->md_eq != NULL) { + int cpt = lnet_cpt_of_cookie(md->md_lh.lh_cookie); + + LASSERT(*md->md_eq->eq_refs[cpt] > 0); + (*md->md_eq->eq_refs[cpt])--; + } + + LASSERT(!list_empty(&md->md_list)); + list_del_init(&md->md_list); + lnet_md_free_locked(md); +} + +static int +lnet_md_build(lnet_libmd_t *lmd, lnet_md_t *umd, int unlink) +{ + int i; + unsigned int niov; + int total_length = 0; + + lmd->md_me = NULL; + lmd->md_start = umd->start; + lmd->md_offset = 0; + lmd->md_max_size = umd->max_size; + lmd->md_options = umd->options; + lmd->md_user_ptr = umd->user_ptr; + lmd->md_eq = NULL; + lmd->md_threshold = umd->threshold; + lmd->md_refcount = 0; + lmd->md_flags = (unlink == LNET_UNLINK) ? LNET_MD_FLAG_AUTO_UNLINK : 0; + + if ((umd->options & LNET_MD_IOVEC) != 0) { + + if ((umd->options & LNET_MD_KIOV) != 0) /* Can't specify both */ + return -EINVAL; + + lmd->md_niov = niov = umd->length; + memcpy(lmd->md_iov.iov, umd->start, + niov * sizeof (lmd->md_iov.iov[0])); + + for (i = 0; i < (int)niov; i++) { + /* We take the base address on trust */ + if (lmd->md_iov.iov[i].iov_len <= 0) /* invalid length */ + return -EINVAL; + + total_length += lmd->md_iov.iov[i].iov_len; + } + + lmd->md_length = total_length; + + if ((umd->options & LNET_MD_MAX_SIZE) != 0 && /* max size used */ + (umd->max_size < 0 || + umd->max_size > total_length)) // illegal max_size + return -EINVAL; + + } else if ((umd->options & LNET_MD_KIOV) != 0) { + lmd->md_niov = niov = umd->length; + memcpy(lmd->md_iov.kiov, umd->start, + niov * sizeof (lmd->md_iov.kiov[0])); + + for (i = 0; i < (int)niov; i++) { + /* We take the page pointer on trust */ + if (lmd->md_iov.kiov[i].kiov_offset + + lmd->md_iov.kiov[i].kiov_len > PAGE_CACHE_SIZE ) + return -EINVAL; /* invalid length */ + + total_length += lmd->md_iov.kiov[i].kiov_len; + } + + lmd->md_length = total_length; + + if ((umd->options & LNET_MD_MAX_SIZE) != 0 && /* max size used */ + (umd->max_size < 0 || + umd->max_size > total_length)) // illegal max_size + return -EINVAL; + } else { /* contiguous */ + lmd->md_length = umd->length; + lmd->md_niov = niov = 1; + lmd->md_iov.iov[0].iov_base = umd->start; + lmd->md_iov.iov[0].iov_len = umd->length; + + if ((umd->options & LNET_MD_MAX_SIZE) != 0 && /* max size used */ + (umd->max_size < 0 || + umd->max_size > (int)umd->length)) // illegal max_size + return -EINVAL; + } + + return 0; +} + +/* must be called with resource lock held */ +static int +lnet_md_link(lnet_libmd_t *md, lnet_handle_eq_t eq_handle, int cpt) +{ + struct lnet_res_container *container = the_lnet.ln_md_containers[cpt]; + + /* NB we are passed an allocated, but inactive md. + * if we return success, caller may lnet_md_unlink() it. + * otherwise caller may only lnet_md_free() it. + */ + /* This implementation doesn't know how to create START events or + * disable END events. Best to LASSERT our caller is compliant so + * we find out quickly... */ + /* TODO - reevaluate what should be here in light of + * the removal of the start and end events + * maybe there we shouldn't even allow LNET_EQ_NONE!) + * LASSERT (eq == NULL); + */ + if (!LNetHandleIsInvalid(eq_handle)) { + md->md_eq = lnet_handle2eq(&eq_handle); + + if (md->md_eq == NULL) + return -ENOENT; + + (*md->md_eq->eq_refs[cpt])++; + } + + lnet_res_lh_initialize(container, &md->md_lh); + + LASSERT(list_empty(&md->md_list)); + list_add(&md->md_list, &container->rec_active); + + return 0; +} + +/* must be called with lnet_res_lock held */ +void +lnet_md_deconstruct(lnet_libmd_t *lmd, lnet_md_t *umd) +{ + /* NB this doesn't copy out all the iov entries so when a + * discontiguous MD is copied out, the target gets to know the + * original iov pointer (in start) and the number of entries it had + * and that's all. + */ + umd->start = lmd->md_start; + umd->length = ((lmd->md_options & (LNET_MD_IOVEC | LNET_MD_KIOV)) == 0) ? + lmd->md_length : lmd->md_niov; + umd->threshold = lmd->md_threshold; + umd->max_size = lmd->md_max_size; + umd->options = lmd->md_options; + umd->user_ptr = lmd->md_user_ptr; + lnet_eq2handle(&umd->eq_handle, lmd->md_eq); +} + +int +lnet_md_validate(lnet_md_t *umd) +{ + if (umd->start == NULL && umd->length != 0) { + CERROR("MD start pointer can not be NULL with length %u\n", + umd->length); + return -EINVAL; + } + + if ((umd->options & (LNET_MD_KIOV | LNET_MD_IOVEC)) != 0 && + umd->length > LNET_MAX_IOV) { + CERROR("Invalid option: too many fragments %u, %d max\n", + umd->length, LNET_MAX_IOV); + return -EINVAL; + } + + return 0; +} + +/** + * Create a memory descriptor and attach it to a ME + * + * \param meh A handle for a ME to associate the new MD with. + * \param umd Provides initial values for the user-visible parts of a MD. + * Other than its use for initialization, there is no linkage between this + * structure and the MD maintained by the LNet. + * \param unlink A flag to indicate whether the MD is automatically unlinked + * when it becomes inactive, either because the operation threshold drops to + * zero or because the available memory becomes less than \a umd.max_size. + * (Note that the check for unlinking a MD only occurs after the completion + * of a successful operation on the MD.) The value LNET_UNLINK enables auto + * unlinking; the value LNET_RETAIN disables it. + * \param handle On successful returns, a handle to the newly created MD is + * saved here. This handle can be used later in LNetMDUnlink(). + * + * \retval 0 On success. + * \retval -EINVAL If \a umd is not valid. + * \retval -ENOMEM If new MD cannot be allocated. + * \retval -ENOENT Either \a meh or \a umd.eq_handle does not point to a + * valid object. Note that it's OK to supply a NULL \a umd.eq_handle by + * calling LNetInvalidateHandle() on it. + * \retval -EBUSY If the ME pointed to by \a meh is already associated with + * a MD. + */ +int +LNetMDAttach(lnet_handle_me_t meh, lnet_md_t umd, + lnet_unlink_t unlink, lnet_handle_md_t *handle) +{ + LIST_HEAD (matches); + LIST_HEAD (drops); + struct lnet_me *me; + struct lnet_libmd *md; + int cpt; + int rc; + + LASSERT (the_lnet.ln_init); + LASSERT (the_lnet.ln_refcount > 0); + + if (lnet_md_validate(&umd) != 0) + return -EINVAL; + + if ((umd.options & (LNET_MD_OP_GET | LNET_MD_OP_PUT)) == 0) { + CERROR("Invalid option: no MD_OP set\n"); + return -EINVAL; + } + + md = lnet_md_alloc(&umd); + if (md == NULL) + return -ENOMEM; + + rc = lnet_md_build(md, &umd, unlink); + cpt = lnet_cpt_of_cookie(meh.cookie); + + lnet_res_lock(cpt); + if (rc != 0) + goto failed; + + me = lnet_handle2me(&meh); + if (me == NULL) + rc = -ENOENT; + else if (me->me_md != NULL) + rc = -EBUSY; + else + rc = lnet_md_link(md, umd.eq_handle, cpt); + + if (rc != 0) + goto failed; + + /* attach this MD to portal of ME and check if it matches any + * blocked msgs on this portal */ + lnet_ptl_attach_md(me, md, &matches, &drops); + + lnet_md2handle(handle, md); + + lnet_res_unlock(cpt); + + lnet_drop_delayed_msg_list(&drops, "Bad match"); + lnet_recv_delayed_msg_list(&matches); + + return 0; + + failed: + lnet_md_free_locked(md); + + lnet_res_unlock(cpt); + return rc; +} +EXPORT_SYMBOL(LNetMDAttach); + +/** + * Create a "free floating" memory descriptor - a MD that is not associated + * with a ME. Such MDs are usually used in LNetPut() and LNetGet() operations. + * + * \param umd,unlink See the discussion for LNetMDAttach(). + * \param handle On successful returns, a handle to the newly created MD is + * saved here. This handle can be used later in LNetMDUnlink(), LNetPut(), + * and LNetGet() operations. + * + * \retval 0 On success. + * \retval -EINVAL If \a umd is not valid. + * \retval -ENOMEM If new MD cannot be allocated. + * \retval -ENOENT \a umd.eq_handle does not point to a valid EQ. Note that + * it's OK to supply a NULL \a umd.eq_handle by calling + * LNetInvalidateHandle() on it. + */ +int +LNetMDBind(lnet_md_t umd, lnet_unlink_t unlink, lnet_handle_md_t *handle) +{ + lnet_libmd_t *md; + int cpt; + int rc; + + LASSERT (the_lnet.ln_init); + LASSERT (the_lnet.ln_refcount > 0); + + if (lnet_md_validate(&umd) != 0) + return -EINVAL; + + if ((umd.options & (LNET_MD_OP_GET | LNET_MD_OP_PUT)) != 0) { + CERROR("Invalid option: GET|PUT illegal on active MDs\n"); + return -EINVAL; + } + + md = lnet_md_alloc(&umd); + if (md == NULL) + return -ENOMEM; + + rc = lnet_md_build(md, &umd, unlink); + + cpt = lnet_res_lock_current(); + if (rc != 0) + goto failed; + + rc = lnet_md_link(md, umd.eq_handle, cpt); + if (rc != 0) + goto failed; + + lnet_md2handle(handle, md); + + lnet_res_unlock(cpt); + return 0; + + failed: + lnet_md_free_locked(md); + + lnet_res_unlock(cpt); + return rc; +} +EXPORT_SYMBOL(LNetMDBind); + +/** + * Unlink the memory descriptor from any ME it may be linked to and release + * the internal resources associated with it. + * + * This function does not free the memory region associated with the MD; + * i.e., the memory the user allocated for this MD. If the ME associated with + * this MD is not NULL and was created with auto unlink enabled, the ME is + * unlinked as well (see LNetMEAttach()). + * + * Explicitly unlinking a MD via this function call has the same behavior as + * a MD that has been automatically unlinked, except that no LNET_EVENT_UNLINK + * is generated in the latter case. + * + * An unlinked event can be reported in two ways: + * - If there's no pending operations on the MD, it's unlinked immediately + * and an LNET_EVENT_UNLINK event is logged before this function returns. + * - Otherwise, the MD is only marked for deletion when this function + * returns, and the unlinked event will be piggybacked on the event of + * the completion of the last operation by setting the unlinked field of + * the event. No dedicated LNET_EVENT_UNLINK event is generated. + * + * Note that in both cases the unlinked field of the event is always set; no + * more event will happen on the MD after such an event is logged. + * + * \param mdh A handle for the MD to be unlinked. + * + * \retval 0 On success. + * \retval -ENOENT If \a mdh does not point to a valid MD object. + */ +int +LNetMDUnlink (lnet_handle_md_t mdh) +{ + lnet_event_t ev; + lnet_libmd_t *md; + int cpt; + + LASSERT(the_lnet.ln_init); + LASSERT(the_lnet.ln_refcount > 0); + + cpt = lnet_cpt_of_cookie(mdh.cookie); + lnet_res_lock(cpt); + + md = lnet_handle2md(&mdh); + if (md == NULL) { + lnet_res_unlock(cpt); + return -ENOENT; + } + + /* If the MD is busy, lnet_md_unlink just marks it for deletion, and + * when the NAL is done, the completion event flags that the MD was + * unlinked. Otherwise, we enqueue an event now... */ + + if (md->md_eq != NULL && + md->md_refcount == 0) { + lnet_build_unlink_event(md, &ev); + lnet_eq_enqueue_event(md->md_eq, &ev); + } + + lnet_md_unlink(md); + + lnet_res_unlock(cpt); + return 0; +} +EXPORT_SYMBOL(LNetMDUnlink); |