diff options
Diffstat (limited to 'fs/xfs/xfs_log_rlimit.c')
| -rw-r--r-- | fs/xfs/xfs_log_rlimit.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/fs/xfs/xfs_log_rlimit.c b/fs/xfs/xfs_log_rlimit.c new file mode 100644 index 000000000000..bbcec0bbc12d --- /dev/null +++ b/fs/xfs/xfs_log_rlimit.c @@ -0,0 +1,147 @@ +/* + * 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_log.h" +#include "xfs_trans.h" +#include "xfs_ag.h" +#include "xfs_sb.h" +#include "xfs_mount.h" +#include "xfs_trans_space.h" +#include "xfs_bmap_btree.h" +#include "xfs_inode.h" +#include "xfs_da_btree.h" +#include "xfs_attr_leaf.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_sb.sb_blocksize) - + 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; +} + +/* + * 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; + } +} + +/* + * 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); +} |