rw.c

lustre 1.6.5 source code

/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
 * vim:expandtab:shiftwidth=8:tabstop=8:
 *
 * Lustre Light block IO
 *
 *  Copyright (c) 2002-2004 Cluster File Systems, Inc.
 *
 *   This file is part of Lustre, http://www.lustre.org.
 *
 *   Lustre is free software; you can redistribute it and/or
 *   modify it under the terms of version 2 of the GNU General Public
 *   License as published by the Free Software Foundation.
 *
 *   Lustre 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 for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with Lustre; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#define DEBUG_SUBSYSTEM S_LLITE

#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/queue.h>
#include <fcntl.h>
#include <sys/uio.h>

#include <sysio.h>
#ifdef HAVE_XTIO_H
#include <xtio.h>
#endif
#include <fs.h>
#include <mount.h>
#include <inode.h>
#ifdef HAVE_FILE_H
#include <file.h>
#endif

#undef LIST_HEAD

#include "llite_lib.h"

struct llu_io_group
{
        struct obd_io_group    *lig_oig;
        struct inode           *lig_inode;
        struct lustre_rw_params *lig_params;
        int                     lig_maxpages;
        int                     lig_npages;
        __u64                   lig_rwcount;
        struct ll_async_page   *lig_llaps;
        struct page            *lig_pages;
        void                   *lig_llap_cookies;
};

#define LLU_IO_GROUP_SIZE(x) \
        (sizeof(struct llu_io_group) + \
         (sizeof(struct ll_async_page) + \
          sizeof(struct page) + \
          llap_cookie_size) * (x))

struct llu_io_session
{
        struct inode           *lis_inode;
        int                     lis_cmd;
        int                     lis_max_groups;
        int                     lis_ngroups;
        struct llu_io_group    *lis_groups[0];
};
#define LLU_IO_SESSION_SIZE(x)  \
        (sizeof(struct llu_io_session) + (x) * 2 * sizeof(void *))


typedef ssize_t llu_file_piov_t(const struct iovec *iovec, int iovlen,
                                _SYSIO_OFF_T pos, ssize_t len,
                                void *private);

size_t llap_cookie_size;

static int llu_lock_to_stripe_offset(struct inode *inode, struct ldlm_lock *lock)
{
        struct llu_inode_info *lli = llu_i2info(inode);
        struct lov_stripe_md *lsm = lli->lli_smd;
        struct obd_export *exp = llu_i2obdexp(inode);
        struct {
                char name[16];
                struct ldlm_lock *lock;
                struct lov_stripe_md *lsm;
        } key = { .name = "lock_to_stripe", .lock = lock, .lsm = lsm };
        __u32 stripe, vallen = sizeof(stripe);
        int rc;
        ENTRY;

        if (lsm->lsm_stripe_count == 1)
                RETURN(0);

        /* get our offset in the lov */
        rc = obd_get_info(exp, sizeof(key), &key, &vallen, &stripe);
        if (rc != 0) {
                CERROR("obd_get_info: rc = %d\n", rc);
                LBUG();
        }
        LASSERT(stripe < lsm->lsm_stripe_count);
        RETURN(stripe);
}

int llu_extent_lock_cancel_cb(struct ldlm_lock *lock,
                                    struct ldlm_lock_desc *new, void *data,
                                    int flag)
{
        struct lustre_handle lockh = { 0 };
        int rc;
        ENTRY;

        if ((unsigned long)data > 0 && (unsigned long)data < 0x1000) {
                LDLM_ERROR(lock, "cancelling lock with bad data %p", data);
                LBUG();
        }

        switch (flag) {
        case LDLM_CB_BLOCKING:
                ldlm_lock2handle(lock, &lockh);
                rc = ldlm_cli_cancel(&lockh);
                if (rc != ELDLM_OK)
                        CERROR("ldlm_cli_cancel failed: %d\n", rc);
                break;
        case LDLM_CB_CANCELING: {
                struct inode *inode;
                struct llu_inode_info *lli;
                struct lov_stripe_md *lsm;
                __u32 stripe;
                __u64 kms;

                /* This lock wasn't granted, don't try to evict pages */
                if (lock->l_req_mode != lock->l_granted_mode)
                        RETURN(0);

                inode = llu_inode_from_lock(lock);
                if (!inode)
                        RETURN(0);
                lli= llu_i2info(inode);
                if (!lli)
                        goto iput;
                if (!lli->lli_smd)
                        goto iput;
                lsm = lli->lli_smd;

                stripe = llu_lock_to_stripe_offset(inode, lock);
                lock_res_and_lock(lock);
                kms = ldlm_extent_shift_kms(lock,
                                            lsm->lsm_oinfo[stripe]->loi_kms);
                unlock_res_and_lock(lock);
                if (lsm->lsm_oinfo[stripe]->loi_kms != kms)
                        LDLM_DEBUG(lock, "updating kms from "LPU64" to "LPU64,
                                   lsm->lsm_oinfo[stripe]->loi_kms, kms);
                lsm->lsm_oinfo[stripe]->loi_kms = kms;
iput:
                I_RELE(inode);
                break;
        }
        default:
                LBUG();
        }

        RETURN(0);
}

static int llu_glimpse_callback(struct ldlm_lock *lock, void *reqp)
{
        struct ptlrpc_request *req = reqp;
        struct inode *inode = llu_inode_from_lock(lock);
        struct llu_inode_info *lli;
        struct ost_lvb *lvb;
        int size[2] = { sizeof(struct ptlrpc_body), sizeof(*lvb) };
        int rc, stripe = 0;
        ENTRY;

        if (inode == NULL)
                GOTO(out, rc = -ELDLM_NO_LOCK_DATA);
        lli = llu_i2info(inode);
        if (lli == NULL)
                GOTO(iput, rc = -ELDLM_NO_LOCK_DATA);
        if (lli->lli_smd == NULL)
                GOTO(iput, rc = -ELDLM_NO_LOCK_DATA);

        /* First, find out which stripe index this lock corresponds to. */
        if (lli->lli_smd->lsm_stripe_count > 1)
                stripe = llu_lock_to_stripe_offset(inode, lock);

        rc = lustre_pack_reply(req, 2, size, NULL);
        if (rc)
                GOTO(iput, rc);

        lvb = lustre_msg_buf(req->rq_repmsg, REPLY_REC_OFF, sizeof(*lvb));
        lvb->lvb_size = lli->lli_smd->lsm_oinfo[stripe]->loi_kms;

        LDLM_DEBUG(lock, "i_size: %llu -> stripe number %u -> kms "LPU64,
                   (long long)llu_i2stat(inode)->st_size, stripe,lvb->lvb_size);
 iput:
        I_RELE(inode);
 out:
        /* These errors are normal races, so we don't want to fill the console
         * with messages by calling ptlrpc_error() */
        if (rc == -ELDLM_NO_LOCK_DATA)
                lustre_pack_reply(req, 1, NULL, NULL);

        req->rq_status = rc;
        return rc;
}

/* NB: lov_merge_size will prefer locally cached writes if they extend the
 * file (because it prefers KMS over RSS when larger) */
int llu_glimpse_size(struct inode *inode)
{
        struct llu_inode_info *lli = llu_i2info(inode);
        struct intnl_stat *st = llu_i2stat(inode);
        struct llu_sb_info *sbi = llu_i2sbi(inode);
        struct lustre_handle lockh = { 0 };
        struct ldlm_enqueue_info einfo = { 0 };
        struct obd_info oinfo = { { { 0 } } };
        struct ost_lvb lvb;
        int rc;
        ENTRY;

        CDEBUG(D_DLMTRACE, "Glimpsing inode %llu\n", (long long)st->st_ino);

        if (!lli->lli_smd) {
                CDEBUG(D_DLMTRACE, "No objects for inode %llu\n", 
                       (long long)st->st_ino);
                RETURN(0);
        }

        einfo.ei_type = LDLM_EXTENT;
        einfo.ei_mode = LCK_PR;
        einfo.ei_cb_bl = osc_extent_blocking_cb;
        einfo.ei_cb_cp = ldlm_completion_ast;
        einfo.ei_cb_gl = llu_glimpse_callback;
        einfo.ei_cbdata = inode;

        oinfo.oi_policy.l_extent.end = OBD_OBJECT_EOF;
        oinfo.oi_lockh = &lockh;
        oinfo.oi_md = lli->lli_smd;
        oinfo.oi_flags = LDLM_FL_HAS_INTENT;

        rc = obd_enqueue_rqset(sbi->ll_osc_exp, &oinfo, &einfo);
        if (rc) {
                CERROR("obd_enqueue returned rc %d, returning -EIO\n", rc);
                RETURN(rc > 0 ? -EIO : rc);
        }

        inode_init_lvb(inode, &lvb);
        rc = obd_merge_lvb(sbi->ll_osc_exp, lli->lli_smd, &lvb, 0);
        st->st_size = lvb.lvb_size;
        st->st_blocks = lvb.lvb_blocks;
        /* handle st_blocks overflow gracefully */
        if (st->st_blocks < lvb.lvb_blocks)
                st->st_blocks = ~0UL;
        st->st_mtime = lvb.lvb_mtime;
        st->st_atime = lvb.lvb_atime;
        st->st_ctime = lvb.lvb_ctime;

        CDEBUG(D_DLMTRACE, "glimpse: size: "LPU64", blocks: "LPU64"\n",
               (__u64)st->st_size, (__u64)st->st_blocks);

        RETURN(rc);
}

int llu_extent_lock(struct ll_file_data *fd, struct inode *inode,
                    struct lov_stripe_md *lsm, int mode,
                    ldlm_policy_data_t *policy, struct lustre_handle *lockh,
                    int ast_flags)
{
        struct llu_sb_info *sbi = llu_i2sbi(inode);
        struct intnl_stat *st = llu_i2stat(inode);
        struct ldlm_enqueue_info einfo = { 0 };
        struct obd_info oinfo = { { { 0 } } };
        struct ost_lvb lvb;
        int rc;
        ENTRY;

        LASSERT(!lustre_handle_is_used(lockh));
        CLASSERT(ELDLM_OK == 0);

        /* XXX phil: can we do this?  won't it screw the file size up? */
        if ((fd && (fd->fd_flags & LL_FILE_IGNORE_LOCK)) ||
            (sbi->ll_flags & LL_SBI_NOLCK) || mode == LCK_NL)
                RETURN(0);

        CDEBUG(D_DLMTRACE, "Locking inode %llu, start "LPU64" end "LPU64"\n",
               (long long)st->st_ino, policy->l_extent.start,
               policy->l_extent.end);

        einfo.ei_type = LDLM_EXTENT;
        einfo.ei_mode = mode;
        einfo.ei_cb_bl = osc_extent_blocking_cb;
        einfo.ei_cb_cp = ldlm_completion_ast;
        einfo.ei_cb_gl = llu_glimpse_callback;
        einfo.ei_cbdata = inode;

        oinfo.oi_policy = *policy;
        oinfo.oi_lockh = lockh;
        oinfo.oi_md = lsm;
        oinfo.oi_flags = ast_flags;

        rc = obd_enqueue(sbi->ll_osc_exp, &oinfo, &einfo, NULL);
        *policy = oinfo.oi_policy;
        if (rc > 0)
                rc = -EIO;

        inode_init_lvb(inode, &lvb);
        obd_merge_lvb(sbi->ll_osc_exp, lsm, &lvb, 1);
        if (policy->l_extent.start == 0 &&
            policy->l_extent.end == OBD_OBJECT_EOF)
                st->st_size = lvb.lvb_size;

        if (rc == 0) {
                st->st_mtime = lvb.lvb_mtime;
                st->st_atime = lvb.lvb_atime;
                st->st_ctime = lvb.lvb_ctime;
        }

        RETURN(rc);
}

int llu_extent_unlock(struct ll_file_data *fd, struct inode *inode,
                struct lov_stripe_md *lsm, int mode,
                struct lustre_handle *lockh)
{
        struct llu_sb_info *sbi = llu_i2sbi(inode);
        int rc;
        ENTRY;

        CLASSERT(ELDLM_OK == 0);

        /* XXX phil: can we do this?  won't it screw the file size up? */
        if ((fd && (fd->fd_flags & LL_FILE_IGNORE_LOCK)) ||
            (sbi->ll_flags & LL_SBI_NOLCK) || mode == LCK_NL)
                RETURN(0);

        rc = obd_cancel(sbi->ll_osc_exp, lsm, mode, lockh);

        RETURN(rc);
}

#define LLAP_MAGIC 12346789

struct ll_async_page {
        int             llap_magic;
        void           *llap_cookie;
        int             llap_queued;
        struct page    *llap_page;
        struct inode   *llap_inode;
};

static void llu_ap_fill_obdo(void *data, int cmd, struct obdo *oa)
{
        struct ll_async_page *llap;
        struct inode *inode;
        struct lov_stripe_md *lsm;
        obd_flag valid_flags;
        ENTRY;

        llap = LLAP_FROM_COOKIE(data);
        inode = llap->llap_inode;
        lsm = llu_i2info(inode)->lli_smd;

        oa->o_id = lsm->lsm_object_id;
        oa->o_valid = OBD_MD_FLID;
        valid_flags = OBD_MD_FLTYPE | OBD_MD_FLATIME;
        if (cmd & OBD_BRW_WRITE)
                valid_flags |= OBD_MD_FLMTIME | OBD_MD_FLCTIME |
                        OBD_MD_FLUID | OBD_MD_FLGID |
                        OBD_MD_FLFID | OBD_MD_FLGENER;

        obdo_from_inode(oa, inode, valid_flags);
        EXIT;
}

static void llu_ap_update_obdo(void *data, int cmd, struct obdo *oa,
                               obd_valid valid)
{
        struct ll_async_page *llap;
        ENTRY;

        llap = LLAP_FROM_COOKIE(data);
        obdo_from_inode(oa, llap->llap_inode, valid);

        EXIT;
}

/* called for each page in a completed rpc.*/
static int llu_ap_completion(void *data, int cmd, struct obdo *oa, int rc)
{
        struct ll_async_page *llap;
        struct page *page;
        ENTRY;

        llap = LLAP_FROM_COOKIE(data);
        llap->llap_queued = 0;
        page = llap->llap_page;

        if (rc != 0) {
                if (cmd & OBD_BRW_WRITE)
                        CERROR("writeback error on page %p index %ld: %d\n",
                               page, page->index, rc);
        }
        RETURN(0);
}

static struct obd_async_page_ops llu_async_page_ops = {
        .ap_make_ready =        NULL,
        .ap_refresh_count =     NULL,
        .ap_fill_obdo =         llu_ap_fill_obdo,
        .ap_update_obdo =       llu_ap_update_obdo,
        .ap_completion =        llu_ap_completion,
};

static int llu_queue_pio(int cmd, struct llu_io_group *group,
                         char *buf, size_t count, loff_t pos)
{
        struct llu_inode_info *lli = llu_i2info(group->lig_inode);
        struct intnl_stat *st = llu_i2stat(group->lig_inode);
        struct lov_stripe_md *lsm = lli->lli_smd;
        struct obd_export *exp = llu_i2obdexp(group->lig_inode);
        struct page *pages = &group->lig_pages[group->lig_npages],*page = pages;
        struct ll_async_page *llap = &group->lig_llaps[group->lig_npages];
        void *llap_cookie = group->lig_llap_cookies +
                llap_cookie_size * group->lig_npages;
        int i, rc, npages = 0, ret_bytes = 0;
        int local_lock;
        ENTRY;

        if (!exp)
                RETURN(-EINVAL);

        local_lock = group->lig_params->lrp_lock_mode != LCK_NL;
        /* prepare the pages array */
	do {
                unsigned long index, offset, bytes;