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Release 4.11 fs/xfs/libxfs/xfs_log_rlimit.c

Directory: fs/xfs/libxfs
/*
 * Copyright (c) 2013 Jie Liu.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would 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 this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_da_format.h"
#include "xfs_trans_space.h"
#include "xfs_inode.h"
#include "xfs_da_btree.h"
#include "xfs_attr_leaf.h"
#include "xfs_bmap_btree.h"

/*
 * Calculate the maximum length in bytes that would be required for a local
 * attribute value as large attributes out of line are not logged.
 */

STATIC int xfs_log_calc_max_attrsetm_res( struct xfs_mount *mp) { int size; int nblks; size = xfs_attr_leaf_entsize_local_max(mp->m_attr_geo->blksize) - MAXNAMELEN - 1; nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK); nblks += XFS_B_TO_FSB(mp, size); nblks += XFS_NEXTENTADD_SPACE_RES(mp, size, XFS_ATTR_FORK); return M_RES(mp)->tr_attrsetm.tr_logres + M_RES(mp)->tr_attrsetrt.tr_logres * nblks; }

Contributors

PersonTokensPropCommitsCommitProp
Jie Liu7996.34%150.00%
Dave Chinner33.66%150.00%
Total82100.00%2100.00%

/* * Iterate over the log space reservation table to figure out and return * the maximum one in terms of the pre-calculated values which were done * at mount time. */
STATIC void xfs_log_get_max_trans_res( struct xfs_mount *mp, struct xfs_trans_res *max_resp) { struct xfs_trans_res *resp; struct xfs_trans_res *end_resp; int log_space = 0; int attr_space; attr_space = xfs_log_calc_max_attrsetm_res(mp); resp = (struct xfs_trans_res *)M_RES(mp); end_resp = (struct xfs_trans_res *)(M_RES(mp) + 1); for (; resp < end_resp; resp++) { int tmp = resp->tr_logcount > 1 ? resp->tr_logres * resp->tr_logcount : resp->tr_logres; if (log_space < tmp) { log_space = tmp; *max_resp = *resp; /* struct copy */ } } if (attr_space > log_space) { *max_resp = M_RES(mp)->tr_attrsetm; /* struct copy */ max_resp->tr_logres = attr_space; } }

Contributors

PersonTokensPropCommitsCommitProp
Jie Liu146100.00%1100.00%
Total146100.00%1100.00%

/* * Calculate the minimum valid log size for the given superblock configuration. * Used to calculate the minimum log size at mkfs time, and to determine if * the log is large enough or not at mount time. Returns the minimum size in * filesystem block size units. */
int xfs_log_calc_minimum_size( struct xfs_mount *mp) { struct xfs_trans_res tres = {0}; int max_logres; int min_logblks = 0; int lsunit = 0; xfs_log_get_max_trans_res(mp, &tres); max_logres = xfs_log_calc_unit_res(mp, tres.tr_logres); if (tres.tr_logcount > 1) max_logres *= tres.tr_logcount; if (xfs_sb_version_haslogv2(&mp->m_sb) && mp->m_sb.sb_logsunit > 1) lsunit = BTOBB(mp->m_sb.sb_logsunit); /* * Two factors should be taken into account for calculating the minimum * log space. * 1) The fundamental limitation is that no single transaction can be * larger than half size of the log. * * From mkfs.xfs, this is considered by the XFS_MIN_LOG_FACTOR * define, which is set to 3. That means we can definitely fit * maximally sized 2 transactions in the log. We'll use this same * value here. * * 2) If the lsunit option is specified, a transaction requires 2 LSU * for the reservation because there are two log writes that can * require padding - the transaction data and the commit record which * are written separately and both can require padding to the LSU. * Consider that we can have an active CIL reservation holding 2*LSU, * but the CIL is not over a push threshold, in this case, if we * don't have enough log space for at one new transaction, which * includes another 2*LSU in the reservation, we will run into dead * loop situation in log space grant procedure. i.e. * xlog_grant_head_wait(). * * Hence the log size needs to be able to contain two maximally sized * and padded transactions, which is (2 * (2 * LSU + maxlres)). * * Also, the log size should be a multiple of the log stripe unit, round * it up to lsunit boundary if lsunit is specified. */ if (lsunit) { min_logblks = roundup_64(BTOBB(max_logres), lsunit) + 2 * lsunit; } else min_logblks = BTOBB(max_logres) + 2 * BBSIZE; min_logblks *= XFS_MIN_LOG_FACTOR; return XFS_BB_TO_FSB(mp, min_logblks); }

Contributors

PersonTokensPropCommitsCommitProp
Jie Liu140100.00%2100.00%
Total140100.00%2100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Jie Liu39395.62%228.57%
Dave Chinner184.38%571.43%
Total411100.00%7100.00%
Directory: fs/xfs/libxfs
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