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-rw-r--r--fs/xfs/libxfs/xfs_trans_resv.c1028
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diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c
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+++ b/fs/xfs/libxfs/xfs_trans_resv.c
@@ -0,0 +1,1028 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
+ * Copyright (C) 2010 Red Hat, Inc.
+ * All Rights Reserved.
+ */
+#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_da_btree.h"
+#include "xfs_inode.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_quota.h"
+#include "xfs_trans.h"
+#include "xfs_qm.h"
+#include "xfs_trans_space.h"
+
+#define _ALLOC true
+#define _FREE false
+
+/*
+ * A buffer has a format structure overhead in the log in addition
+ * to the data, so we need to take this into account when reserving
+ * space in a transaction for a buffer. Round the space required up
+ * to a multiple of 128 bytes so that we don't change the historical
+ * reservation that has been used for this overhead.
+ */
+STATIC uint
+xfs_buf_log_overhead(void)
+{
+ return round_up(sizeof(struct xlog_op_header) +
+ sizeof(struct xfs_buf_log_format), 128);
+}
+
+/*
+ * Calculate out transaction log reservation per item in bytes.
+ *
+ * The nbufs argument is used to indicate the number of items that
+ * will be changed in a transaction. size is used to tell how many
+ * bytes should be reserved per item.
+ */
+STATIC uint
+xfs_calc_buf_res(
+ uint nbufs,
+ uint size)
+{
+ return nbufs * (size + xfs_buf_log_overhead());
+}
+
+/*
+ * Per-extent log reservation for the btree changes involved in freeing or
+ * allocating an extent. In classic XFS there were two trees that will be
+ * modified (bnobt + cntbt). With rmap enabled, there are three trees
+ * (rmapbt). The number of blocks reserved is based on the formula:
+ *
+ * num trees * ((2 blocks/level * max depth) - 1)
+ *
+ * Keep in mind that max depth is calculated separately for each type of tree.
+ */
+uint
+xfs_allocfree_block_count(
+ struct xfs_mount *mp,
+ uint num_ops)
+{
+ uint blocks;
+
+ blocks = num_ops * 2 * (2 * mp->m_alloc_maxlevels - 1);
+ if (xfs_has_rmapbt(mp))
+ blocks += num_ops * (2 * mp->m_rmap_maxlevels - 1);
+
+ return blocks;
+}
+
+/*
+ * Per-extent log reservation for refcount btree changes. These are never done
+ * in the same transaction as an allocation or a free, so we compute them
+ * separately.
+ */
+static unsigned int
+xfs_refcountbt_block_count(
+ struct xfs_mount *mp,
+ unsigned int num_ops)
+{
+ return num_ops * (2 * mp->m_refc_maxlevels - 1);
+}
+
+/*
+ * Logging inodes is really tricksy. They are logged in memory format,
+ * which means that what we write into the log doesn't directly translate into
+ * the amount of space they use on disk.
+ *
+ * Case in point - btree format forks in memory format use more space than the
+ * on-disk format. In memory, the buffer contains a normal btree block header so
+ * the btree code can treat it as though it is just another generic buffer.
+ * However, when we write it to the inode fork, we don't write all of this
+ * header as it isn't needed. e.g. the root is only ever in the inode, so
+ * there's no need for sibling pointers which would waste 16 bytes of space.
+ *
+ * Hence when we have an inode with a maximally sized btree format fork, then
+ * amount of information we actually log is greater than the size of the inode
+ * on disk. Hence we need an inode reservation function that calculates all this
+ * correctly. So, we log:
+ *
+ * - 4 log op headers for object
+ * - for the ilf, the inode core and 2 forks
+ * - inode log format object
+ * - the inode core
+ * - two inode forks containing bmap btree root blocks.
+ * - the btree data contained by both forks will fit into the inode size,
+ * hence when combined with the inode core above, we have a total of the
+ * actual inode size.
+ * - the BMBT headers need to be accounted separately, as they are
+ * additional to the records and pointers that fit inside the inode
+ * forks.
+ */
+STATIC uint
+xfs_calc_inode_res(
+ struct xfs_mount *mp,
+ uint ninodes)
+{
+ return ninodes *
+ (4 * sizeof(struct xlog_op_header) +
+ sizeof(struct xfs_inode_log_format) +
+ mp->m_sb.sb_inodesize +
+ 2 * XFS_BMBT_BLOCK_LEN(mp));
+}
+
+/*
+ * Inode btree record insertion/removal modifies the inode btree and free space
+ * btrees (since the inobt does not use the agfl). This requires the following
+ * reservation:
+ *
+ * the inode btree: max depth * blocksize
+ * the allocation btrees: 2 trees * (max depth - 1) * block size
+ *
+ * The caller must account for SB and AG header modifications, etc.
+ */
+STATIC uint
+xfs_calc_inobt_res(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(M_IGEO(mp)->inobt_maxlevels,
+ XFS_FSB_TO_B(mp, 1)) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
+ XFS_FSB_TO_B(mp, 1));
+}
+
+/*
+ * The free inode btree is a conditional feature. The behavior differs slightly
+ * from that of the traditional inode btree in that the finobt tracks records
+ * for inode chunks with at least one free inode. A record can be removed from
+ * the tree during individual inode allocation. Therefore the finobt
+ * reservation is unconditional for both the inode chunk allocation and
+ * individual inode allocation (modify) cases.
+ *
+ * Behavior aside, the reservation for finobt modification is equivalent to the
+ * traditional inobt: cover a full finobt shape change plus block allocation.
+ */
+STATIC uint
+xfs_calc_finobt_res(
+ struct xfs_mount *mp)
+{
+ if (!xfs_has_finobt(mp))
+ return 0;
+
+ return xfs_calc_inobt_res(mp);
+}
+
+/*
+ * Calculate the reservation required to allocate or free an inode chunk. This
+ * includes:
+ *
+ * the allocation btrees: 2 trees * (max depth - 1) * block size
+ * the inode chunk: m_ino_geo.ialloc_blks * N
+ *
+ * The size N of the inode chunk reservation depends on whether it is for
+ * allocation or free and which type of create transaction is in use. An inode
+ * chunk free always invalidates the buffers and only requires reservation for
+ * headers (N == 0). An inode chunk allocation requires a chunk sized
+ * reservation on v4 and older superblocks to initialize the chunk. No chunk
+ * reservation is required for allocation on v5 supers, which use ordered
+ * buffers to initialize.
+ */
+STATIC uint
+xfs_calc_inode_chunk_res(
+ struct xfs_mount *mp,
+ bool alloc)
+{
+ uint res, size = 0;
+
+ res = xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
+ XFS_FSB_TO_B(mp, 1));
+ if (alloc) {
+ /* icreate tx uses ordered buffers */
+ if (xfs_has_v3inodes(mp))
+ return res;
+ size = XFS_FSB_TO_B(mp, 1);
+ }
+
+ res += xfs_calc_buf_res(M_IGEO(mp)->ialloc_blks, size);
+ return res;
+}
+
+/*
+ * Per-extent log reservation for the btree changes involved in freeing or
+ * allocating a realtime extent. We have to be able to log as many rtbitmap
+ * blocks as needed to mark inuse XFS_BMBT_MAX_EXTLEN blocks' worth of realtime
+ * extents, as well as the realtime summary block.
+ */
+static unsigned int
+xfs_rtalloc_block_count(
+ struct xfs_mount *mp,
+ unsigned int num_ops)
+{
+ unsigned int blksz = XFS_FSB_TO_B(mp, 1);
+ unsigned int rtbmp_bytes;
+
+ rtbmp_bytes = (XFS_MAX_BMBT_EXTLEN / mp->m_sb.sb_rextsize) / NBBY;
+ return (howmany(rtbmp_bytes, blksz) + 1) * num_ops;
+}
+
+/*
+ * Various log reservation values.
+ *
+ * These are based on the size of the file system block because that is what
+ * most transactions manipulate. Each adds in an additional 128 bytes per
+ * item logged to try to account for the overhead of the transaction mechanism.
+ *
+ * Note: Most of the reservations underestimate the number of allocation
+ * groups into which they could free extents in the xfs_defer_finish() call.
+ * This is because the number in the worst case is quite high and quite
+ * unusual. In order to fix this we need to change xfs_defer_finish() to free
+ * extents in only a single AG at a time. This will require changes to the
+ * EFI code as well, however, so that the EFI for the extents not freed is
+ * logged again in each transaction. See SGI PV #261917.
+ *
+ * Reservation functions here avoid a huge stack in xfs_trans_init due to
+ * register overflow from temporaries in the calculations.
+ */
+
+/*
+ * Compute the log reservation required to handle the refcount update
+ * transaction. Refcount updates are always done via deferred log items.
+ *
+ * This is calculated as:
+ * Data device refcount updates (t1):
+ * the agfs of the ags containing the blocks: nr_ops * sector size
+ * the refcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
+ */
+static unsigned int
+xfs_calc_refcountbt_reservation(
+ struct xfs_mount *mp,
+ unsigned int nr_ops)
+{
+ unsigned int blksz = XFS_FSB_TO_B(mp, 1);
+
+ if (!xfs_has_reflink(mp))
+ return 0;
+
+ return xfs_calc_buf_res(nr_ops, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_refcountbt_block_count(mp, nr_ops), blksz);
+}
+
+/*
+ * In a write transaction we can allocate a maximum of 2
+ * extents. This gives (t1):
+ * the inode getting the new extents: inode size
+ * the inode's bmap btree: max depth * block size
+ * the agfs of the ags from which the extents are allocated: 2 * sector
+ * the superblock free block counter: sector size
+ * the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
+ * Or, if we're writing to a realtime file (t2):
+ * the inode getting the new extents: inode size
+ * the inode's bmap btree: max depth * block size
+ * the agfs of the ags from which the extents are allocated: 2 * sector
+ * the superblock free block counter: sector size
+ * the realtime bitmap: ((XFS_BMBT_MAX_EXTLEN / rtextsize) / NBBY) bytes
+ * the realtime summary: 1 block
+ * the allocation btrees: 2 trees * (2 * max depth - 1) * block size
+ * And the bmap_finish transaction can free bmap blocks in a join (t3):
+ * the agfs of the ags containing the blocks: 2 * sector size
+ * the agfls of the ags containing the blocks: 2 * sector size
+ * the super block free block counter: sector size
+ * the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
+ * And any refcount updates that happen in a separate transaction (t4).
+ */
+STATIC uint
+xfs_calc_write_reservation(
+ struct xfs_mount *mp,
+ bool for_minlogsize)
+{
+ unsigned int t1, t2, t3, t4;
+ unsigned int blksz = XFS_FSB_TO_B(mp, 1);
+
+ t1 = xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK), blksz) +
+ xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2), blksz);
+
+ if (xfs_has_realtime(mp)) {
+ t2 = xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK),
+ blksz) +
+ xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_rtalloc_block_count(mp, 1), blksz) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1), blksz);
+ } else {
+ t2 = 0;
+ }
+
+ t3 = xfs_calc_buf_res(5, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2), blksz);
+
+ /*
+ * In the early days of reflink, we included enough reservation to log
+ * two refcountbt splits for each transaction. The codebase runs
+ * refcountbt updates in separate transactions now, so to compute the
+ * minimum log size, add the refcountbtree splits back to t1 and t3 and
+ * do not account them separately as t4. Reflink did not support
+ * realtime when the reservations were established, so no adjustment to
+ * t2 is needed.
+ */
+ if (for_minlogsize) {
+ unsigned int adj = 0;
+
+ if (xfs_has_reflink(mp))
+ adj = xfs_calc_buf_res(
+ xfs_refcountbt_block_count(mp, 2),
+ blksz);
+ t1 += adj;
+ t3 += adj;
+ return XFS_DQUOT_LOGRES(mp) + max3(t1, t2, t3);
+ }
+
+ t4 = xfs_calc_refcountbt_reservation(mp, 1);
+ return XFS_DQUOT_LOGRES(mp) + max(t4, max3(t1, t2, t3));
+}
+
+unsigned int
+xfs_calc_write_reservation_minlogsize(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_write_reservation(mp, true);
+}
+
+/*
+ * In truncating a file we free up to two extents at once. We can modify (t1):
+ * the inode being truncated: inode size
+ * the inode's bmap btree: (max depth + 1) * block size
+ * And the bmap_finish transaction can free the blocks and bmap blocks (t2):
+ * the agf for each of the ags: 4 * sector size
+ * the agfl for each of the ags: 4 * sector size
+ * the super block to reflect the freed blocks: sector size
+ * worst case split in allocation btrees per extent assuming 4 extents:
+ * 4 exts * 2 trees * (2 * max depth - 1) * block size
+ * Or, if it's a realtime file (t3):
+ * the agf for each of the ags: 2 * sector size
+ * the agfl for each of the ags: 2 * sector size
+ * the super block to reflect the freed blocks: sector size
+ * the realtime bitmap:
+ * 2 exts * ((XFS_BMBT_MAX_EXTLEN / rtextsize) / NBBY) bytes
+ * the realtime summary: 2 exts * 1 block
+ * worst case split in allocation btrees per extent assuming 2 extents:
+ * 2 exts * 2 trees * (2 * max depth - 1) * block size
+ * And any refcount updates that happen in a separate transaction (t4).
+ */
+STATIC uint
+xfs_calc_itruncate_reservation(
+ struct xfs_mount *mp,
+ bool for_minlogsize)
+{
+ unsigned int t1, t2, t3, t4;
+ unsigned int blksz = XFS_FSB_TO_B(mp, 1);
+
+ t1 = xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + 1, blksz);
+
+ t2 = xfs_calc_buf_res(9, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 4), blksz);
+
+ if (xfs_has_realtime(mp)) {
+ t3 = xfs_calc_buf_res(5, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_rtalloc_block_count(mp, 2), blksz) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2), blksz);
+ } else {
+ t3 = 0;
+ }
+
+ /*
+ * In the early days of reflink, we included enough reservation to log
+ * four refcountbt splits in the same transaction as bnobt/cntbt
+ * updates. The codebase runs refcountbt updates in separate
+ * transactions now, so to compute the minimum log size, add the
+ * refcount btree splits back here and do not compute them separately
+ * as t4. Reflink did not support realtime when the reservations were
+ * established, so do not adjust t3.
+ */
+ if (for_minlogsize) {
+ if (xfs_has_reflink(mp))
+ t2 += xfs_calc_buf_res(
+ xfs_refcountbt_block_count(mp, 4),
+ blksz);
+
+ return XFS_DQUOT_LOGRES(mp) + max3(t1, t2, t3);
+ }
+
+ t4 = xfs_calc_refcountbt_reservation(mp, 2);
+ return XFS_DQUOT_LOGRES(mp) + max(t4, max3(t1, t2, t3));
+}
+
+unsigned int
+xfs_calc_itruncate_reservation_minlogsize(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_itruncate_reservation(mp, true);
+}
+
+/*
+ * In renaming a files we can modify:
+ * the five inodes involved: 5 * inode size
+ * the two directory btrees: 2 * (max depth + v2) * dir block size
+ * the two directory bmap btrees: 2 * max depth * block size
+ * And the bmap_finish transaction can free dir and bmap blocks (two sets
+ * of bmap blocks) giving:
+ * the agf for the ags in which the blocks live: 3 * sector size
+ * the agfl for the ags in which the blocks live: 3 * sector size
+ * the superblock for the free block count: sector size
+ * the allocation btrees: 3 exts * 2 trees * (2 * max depth - 1) * block size
+ */
+STATIC uint
+xfs_calc_rename_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ max((xfs_calc_inode_res(mp, 5) +
+ xfs_calc_buf_res(2 * XFS_DIROP_LOG_COUNT(mp),
+ XFS_FSB_TO_B(mp, 1))),
+ (xfs_calc_buf_res(7, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 3),
+ XFS_FSB_TO_B(mp, 1))));
+}
+
+/*
+ * For removing an inode from unlinked list at first, we can modify:
+ * the agi hash list and counters: sector size
+ * the on disk inode before ours in the agi hash list: inode cluster size
+ * the on disk inode in the agi hash list: inode cluster size
+ */
+STATIC uint
+xfs_calc_iunlink_remove_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
+ 2 * M_IGEO(mp)->inode_cluster_size;
+}
+
+/*
+ * For creating a link to an inode:
+ * the parent directory inode: inode size
+ * the linked inode: inode size
+ * the directory btree could split: (max depth + v2) * dir block size
+ * the directory bmap btree could join or split: (max depth + v2) * blocksize
+ * And the bmap_finish transaction can free some bmap blocks giving:
+ * the agf for the ag in which the blocks live: sector size
+ * the agfl for the ag in which the blocks live: sector size
+ * the superblock for the free block count: sector size
+ * the allocation btrees: 2 trees * (2 * max depth - 1) * block size
+ */
+STATIC uint
+xfs_calc_link_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ xfs_calc_iunlink_remove_reservation(mp) +
+ max((xfs_calc_inode_res(mp, 2) +
+ xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp),
+ XFS_FSB_TO_B(mp, 1))),
+ (xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
+ XFS_FSB_TO_B(mp, 1))));
+}
+
+/*
+ * For adding an inode to unlinked list we can modify:
+ * the agi hash list: sector size
+ * the on disk inode: inode cluster size
+ */
+STATIC uint
+xfs_calc_iunlink_add_reservation(xfs_mount_t *mp)
+{
+ return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
+ M_IGEO(mp)->inode_cluster_size;
+}
+
+/*
+ * For removing a directory entry we can modify:
+ * the parent directory inode: inode size
+ * the removed inode: inode size
+ * the directory btree could join: (max depth + v2) * dir block size
+ * the directory bmap btree could join or split: (max depth + v2) * blocksize
+ * And the bmap_finish transaction can free the dir and bmap blocks giving:
+ * the agf for the ag in which the blocks live: 2 * sector size
+ * the agfl for the ag in which the blocks live: 2 * sector size
+ * the superblock for the free block count: sector size
+ * the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
+ */
+STATIC uint
+xfs_calc_remove_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ xfs_calc_iunlink_add_reservation(mp) +
+ max((xfs_calc_inode_res(mp, 2) +
+ xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp),
+ XFS_FSB_TO_B(mp, 1))),
+ (xfs_calc_buf_res(4, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2),
+ XFS_FSB_TO_B(mp, 1))));
+}
+
+/*
+ * For create, break it in to the two cases that the transaction
+ * covers. We start with the modify case - allocation done by modification
+ * of the state of existing inodes - and the allocation case.
+ */
+
+/*
+ * For create we can modify:
+ * the parent directory inode: inode size
+ * the new inode: inode size
+ * the inode btree entry: block size
+ * the superblock for the nlink flag: sector size
+ * the directory btree: (max depth + v2) * dir block size
+ * the directory inode's bmap btree: (max depth + v2) * block size
+ * the finobt (record modification and allocation btrees)
+ */
+STATIC uint
+xfs_calc_create_resv_modify(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_inode_res(mp, 2) +
+ xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
+ (uint)XFS_FSB_TO_B(mp, 1) +
+ xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp), XFS_FSB_TO_B(mp, 1)) +
+ xfs_calc_finobt_res(mp);
+}
+
+/*
+ * For icreate we can allocate some inodes giving:
+ * the agi and agf of the ag getting the new inodes: 2 * sectorsize
+ * the superblock for the nlink flag: sector size
+ * the inode chunk (allocation, optional init)
+ * the inobt (record insertion)
+ * the finobt (optional, record insertion)
+ */
+STATIC uint
+xfs_calc_icreate_resv_alloc(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(2, mp->m_sb.sb_sectsize) +
+ mp->m_sb.sb_sectsize +
+ xfs_calc_inode_chunk_res(mp, _ALLOC) +
+ xfs_calc_inobt_res(mp) +
+ xfs_calc_finobt_res(mp);
+}
+
+STATIC uint
+xfs_calc_icreate_reservation(xfs_mount_t *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ max(xfs_calc_icreate_resv_alloc(mp),
+ xfs_calc_create_resv_modify(mp));
+}
+
+STATIC uint
+xfs_calc_create_tmpfile_reservation(
+ struct xfs_mount *mp)
+{
+ uint res = XFS_DQUOT_LOGRES(mp);
+
+ res += xfs_calc_icreate_resv_alloc(mp);
+ return res + xfs_calc_iunlink_add_reservation(mp);
+}
+
+/*
+ * Making a new directory is the same as creating a new file.
+ */
+STATIC uint
+xfs_calc_mkdir_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_icreate_reservation(mp);
+}
+
+
+/*
+ * Making a new symplink is the same as creating a new file, but
+ * with the added blocks for remote symlink data which can be up to 1kB in
+ * length (XFS_SYMLINK_MAXLEN).
+ */
+STATIC uint
+xfs_calc_symlink_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_icreate_reservation(mp) +
+ xfs_calc_buf_res(1, XFS_SYMLINK_MAXLEN);
+}
+
+/*
+ * In freeing an inode we can modify:
+ * the inode being freed: inode size
+ * the super block free inode counter, AGF and AGFL: sector size
+ * the on disk inode (agi unlinked list removal)
+ * the inode chunk (invalidated, headers only)
+ * the inode btree
+ * the finobt (record insertion, removal or modification)
+ *
+ * Note that the inode chunk res. includes an allocfree res. for freeing of the
+ * inode chunk. This is technically extraneous because the inode chunk free is
+ * deferred (it occurs after a transaction roll). Include the extra reservation
+ * anyways since we've had reports of ifree transaction overruns due to too many
+ * agfl fixups during inode chunk frees.
+ */
+STATIC uint
+xfs_calc_ifree_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
+ xfs_calc_iunlink_remove_reservation(mp) +
+ xfs_calc_inode_chunk_res(mp, _FREE) +
+ xfs_calc_inobt_res(mp) +
+ xfs_calc_finobt_res(mp);
+}
+
+/*
+ * When only changing the inode we log the inode and possibly the superblock
+ * We also add a bit of slop for the transaction stuff.
+ */
+STATIC uint
+xfs_calc_ichange_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
+
+}
+
+/*
+ * Growing the data section of the filesystem.
+ * superblock
+ * agi and agf
+ * allocation btrees
+ */
+STATIC uint
+xfs_calc_growdata_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
+ XFS_FSB_TO_B(mp, 1));
+}
+
+/*
+ * Growing the rt section of the filesystem.
+ * In the first set of transactions (ALLOC) we allocate space to the
+ * bitmap or summary files.
+ * superblock: sector size
+ * agf of the ag from which the extent is allocated: sector size
+ * bmap btree for bitmap/summary inode: max depth * blocksize
+ * bitmap/summary inode: inode size
+ * allocation btrees for 1 block alloc: 2 * (2 * maxdepth - 1) * blocksize
+ */
+STATIC uint
+xfs_calc_growrtalloc_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(2, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK),
+ XFS_FSB_TO_B(mp, 1)) +
+ xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
+ XFS_FSB_TO_B(mp, 1));
+}
+
+/*
+ * Growing the rt section of the filesystem.
+ * In the second set of transactions (ZERO) we zero the new metadata blocks.
+ * one bitmap/summary block: blocksize
+ */
+STATIC uint
+xfs_calc_growrtzero_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(1, mp->m_sb.sb_blocksize);
+}
+
+/*
+ * Growing the rt section of the filesystem.
+ * In the third set of transactions (FREE) we update metadata without
+ * allocating any new blocks.
+ * superblock: sector size
+ * bitmap inode: inode size
+ * summary inode: inode size
+ * one bitmap block: blocksize
+ * summary blocks: new summary size
+ */
+STATIC uint
+xfs_calc_growrtfree_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
+ xfs_calc_inode_res(mp, 2) +
+ xfs_calc_buf_res(1, mp->m_sb.sb_blocksize) +
+ xfs_calc_buf_res(1, mp->m_rsumsize);
+}
+
+/*
+ * Logging the inode modification timestamp on a synchronous write.
+ * inode
+ */
+STATIC uint
+xfs_calc_swrite_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_inode_res(mp, 1);
+}
+
+/*
+ * Logging the inode mode bits when writing a setuid/setgid file
+ * inode
+ */
+STATIC uint
+xfs_calc_writeid_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_inode_res(mp, 1);
+}
+
+/*
+ * Converting the inode from non-attributed to attributed.
+ * the inode being converted: inode size
+ * agf block and superblock (for block allocation)
+ * the new block (directory sized)
+ * bmap blocks for the new directory block
+ * allocation btrees
+ */
+STATIC uint
+xfs_calc_addafork_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(2, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(1, mp->m_dir_geo->blksize) +
+ xfs_calc_buf_res(XFS_DAENTER_BMAP1B(mp, XFS_DATA_FORK) + 1,
+ XFS_FSB_TO_B(mp, 1)) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
+ XFS_FSB_TO_B(mp, 1));
+}
+
+/*
+ * Removing the attribute fork of a file
+ * the inode being truncated: inode size
+ * the inode's bmap btree: max depth * block size
+ * And the bmap_finish transaction can free the blocks and bmap blocks:
+ * the agf for each of the ags: 4 * sector size
+ * the agfl for each of the ags: 4 * sector size
+ * the super block to reflect the freed blocks: sector size
+ * worst case split in allocation btrees per extent assuming 4 extents:
+ * 4 exts * 2 trees * (2 * max depth - 1) * block size
+ */
+STATIC uint
+xfs_calc_attrinval_reservation(
+ struct xfs_mount *mp)
+{
+ return max((xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK),
+ XFS_FSB_TO_B(mp, 1))),
+ (xfs_calc_buf_res(9, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 4),
+ XFS_FSB_TO_B(mp, 1))));
+}
+
+/*
+ * Setting an attribute at mount time.
+ * the inode getting the attribute
+ * the superblock for allocations
+ * the agfs extents are allocated from
+ * the attribute btree * max depth
+ * the inode allocation btree
+ * Since attribute transaction space is dependent on the size of the attribute,
+ * the calculation is done partially at mount time and partially at runtime(see
+ * below).
+ */
+STATIC uint
+xfs_calc_attrsetm_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(XFS_DA_NODE_MAXDEPTH, XFS_FSB_TO_B(mp, 1));
+}
+
+/*
+ * Setting an attribute at runtime, transaction space unit per block.
+ * the superblock for allocations: sector size
+ * the inode bmap btree could join or split: max depth * block size
+ * Since the runtime attribute transaction space is dependent on the total
+ * blocks needed for the 1st bmap, here we calculate out the space unit for
+ * one block so that the caller could figure out the total space according
+ * to the attibute extent length in blocks by:
+ * ext * M_RES(mp)->tr_attrsetrt.tr_logres
+ */
+STATIC uint
+xfs_calc_attrsetrt_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK),
+ XFS_FSB_TO_B(mp, 1));
+}
+
+/*
+ * Removing an attribute.
+ * the inode: inode size
+ * the attribute btree could join: max depth * block size
+ * the inode bmap btree could join or split: max depth * block size
+ * And the bmap_finish transaction can free the attr blocks freed giving:
+ * the agf for the ag in which the blocks live: 2 * sector size
+ * the agfl for the ag in which the blocks live: 2 * sector size
+ * the superblock for the free block count: sector size
+ * the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
+ */
+STATIC uint
+xfs_calc_attrrm_reservation(
+ struct xfs_mount *mp)
+{
+ return XFS_DQUOT_LOGRES(mp) +
+ max((xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(XFS_DA_NODE_MAXDEPTH,
+ XFS_FSB_TO_B(mp, 1)) +
+ (uint)XFS_FSB_TO_B(mp,
+ XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)) +
+ xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK), 0)),
+ (xfs_calc_buf_res(5, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2),
+ XFS_FSB_TO_B(mp, 1))));
+}
+
+/*
+ * Clearing a bad agino number in an agi hash bucket.
+ */
+STATIC uint
+xfs_calc_clear_agi_bucket_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
+}
+
+/*
+ * Adjusting quota limits.
+ * the disk quota buffer: sizeof(struct xfs_disk_dquot)
+ */
+STATIC uint
+xfs_calc_qm_setqlim_reservation(void)
+{
+ return xfs_calc_buf_res(1, sizeof(struct xfs_disk_dquot));
+}
+
+/*
+ * Allocating quota on disk if needed.
+ * the write transaction log space for quota file extent allocation
+ * the unit of quota allocation: one system block size
+ */
+STATIC uint
+xfs_calc_qm_dqalloc_reservation(
+ struct xfs_mount *mp,
+ bool for_minlogsize)
+{
+ return xfs_calc_write_reservation(mp, for_minlogsize) +
+ xfs_calc_buf_res(1,
+ XFS_FSB_TO_B(mp, XFS_DQUOT_CLUSTER_SIZE_FSB) - 1);
+}
+
+unsigned int
+xfs_calc_qm_dqalloc_reservation_minlogsize(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_qm_dqalloc_reservation(mp, true);
+}
+
+/*
+ * Syncing the incore super block changes to disk.
+ * the super block to reflect the changes: sector size
+ */
+STATIC uint
+xfs_calc_sb_reservation(
+ struct xfs_mount *mp)
+{
+ return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
+}
+
+void
+xfs_trans_resv_calc(
+ struct xfs_mount *mp,
+ struct xfs_trans_resv *resp)
+{
+ int logcount_adj = 0;
+
+ /*
+ * The following transactions are logged in physical format and
+ * require a permanent reservation on space.
+ */
+ resp->tr_write.tr_logres = xfs_calc_write_reservation(mp, false);
+ resp->tr_write.tr_logcount = XFS_WRITE_LOG_COUNT;
+ resp->tr_write.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_itruncate.tr_logres = xfs_calc_itruncate_reservation(mp, false);
+ resp->tr_itruncate.tr_logcount = XFS_ITRUNCATE_LOG_COUNT;
+ resp->tr_itruncate.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_rename.tr_logres = xfs_calc_rename_reservation(mp);
+ resp->tr_rename.tr_logcount = XFS_RENAME_LOG_COUNT;
+ resp->tr_rename.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_link.tr_logres = xfs_calc_link_reservation(mp);
+ resp->tr_link.tr_logcount = XFS_LINK_LOG_COUNT;
+ resp->tr_link.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_remove.tr_logres = xfs_calc_remove_reservation(mp);
+ resp->tr_remove.tr_logcount = XFS_REMOVE_LOG_COUNT;
+ resp->tr_remove.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_symlink.tr_logres = xfs_calc_symlink_reservation(mp);
+ resp->tr_symlink.tr_logcount = XFS_SYMLINK_LOG_COUNT;
+ resp->tr_symlink.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_create.tr_logres = xfs_calc_icreate_reservation(mp);
+ resp->tr_create.tr_logcount = XFS_CREATE_LOG_COUNT;
+ resp->tr_create.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_create_tmpfile.tr_logres =
+ xfs_calc_create_tmpfile_reservation(mp);
+ resp->tr_create_tmpfile.tr_logcount = XFS_CREATE_TMPFILE_LOG_COUNT;
+ resp->tr_create_tmpfile.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_mkdir.tr_logres = xfs_calc_mkdir_reservation(mp);
+ resp->tr_mkdir.tr_logcount = XFS_MKDIR_LOG_COUNT;
+ resp->tr_mkdir.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_ifree.tr_logres = xfs_calc_ifree_reservation(mp);
+ resp->tr_ifree.tr_logcount = XFS_INACTIVE_LOG_COUNT;
+ resp->tr_ifree.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_addafork.tr_logres = xfs_calc_addafork_reservation(mp);
+ resp->tr_addafork.tr_logcount = XFS_ADDAFORK_LOG_COUNT;
+ resp->tr_addafork.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_attrinval.tr_logres = xfs_calc_attrinval_reservation(mp);
+ resp->tr_attrinval.tr_logcount = XFS_ATTRINVAL_LOG_COUNT;
+ resp->tr_attrinval.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_attrsetm.tr_logres = xfs_calc_attrsetm_reservation(mp);
+ resp->tr_attrsetm.tr_logcount = XFS_ATTRSET_LOG_COUNT;
+ resp->tr_attrsetm.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_attrrm.tr_logres = xfs_calc_attrrm_reservation(mp);
+ resp->tr_attrrm.tr_logcount = XFS_ATTRRM_LOG_COUNT;
+ resp->tr_attrrm.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_growrtalloc.tr_logres = xfs_calc_growrtalloc_reservation(mp);
+ resp->tr_growrtalloc.tr_logcount = XFS_DEFAULT_PERM_LOG_COUNT;
+ resp->tr_growrtalloc.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ resp->tr_qm_dqalloc.tr_logres = xfs_calc_qm_dqalloc_reservation(mp,
+ false);
+ resp->tr_qm_dqalloc.tr_logcount = XFS_WRITE_LOG_COUNT;
+ resp->tr_qm_dqalloc.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ /*
+ * The following transactions are logged in logical format with
+ * a default log count.
+ */
+ resp->tr_qm_setqlim.tr_logres = xfs_calc_qm_setqlim_reservation();
+ resp->tr_qm_setqlim.tr_logcount = XFS_DEFAULT_LOG_COUNT;
+
+ resp->tr_sb.tr_logres = xfs_calc_sb_reservation(mp);
+ resp->tr_sb.tr_logcount = XFS_DEFAULT_LOG_COUNT;
+
+ /* growdata requires permanent res; it can free space to the last AG */
+ resp->tr_growdata.tr_logres = xfs_calc_growdata_reservation(mp);
+ resp->tr_growdata.tr_logcount = XFS_DEFAULT_PERM_LOG_COUNT;
+ resp->tr_growdata.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
+
+ /* The following transaction are logged in logical format */
+ resp->tr_ichange.tr_logres = xfs_calc_ichange_reservation(mp);
+ resp->tr_fsyncts.tr_logres = xfs_calc_swrite_reservation(mp);
+ resp->tr_writeid.tr_logres = xfs_calc_writeid_reservation(mp);
+ resp->tr_attrsetrt.tr_logres = xfs_calc_attrsetrt_reservation(mp);
+ resp->tr_clearagi.tr_logres = xfs_calc_clear_agi_bucket_reservation(mp);
+ resp->tr_growrtzero.tr_logres = xfs_calc_growrtzero_reservation(mp);
+ resp->tr_growrtfree.tr_logres = xfs_calc_growrtfree_reservation(mp);
+
+ /*
+ * Add one logcount for BUI items that appear with rmap or reflink,
+ * one logcount for refcount intent items, and one logcount for rmap
+ * intent items.
+ */
+ if (xfs_has_reflink(mp) || xfs_has_rmapbt(mp))
+ logcount_adj++;
+ if (xfs_has_reflink(mp))
+ logcount_adj++;
+ if (xfs_has_rmapbt(mp))
+ logcount_adj++;
+
+ resp->tr_itruncate.tr_logcount += logcount_adj;
+ resp->tr_write.tr_logcount += logcount_adj;
+ resp->tr_qm_dqalloc.tr_logcount += logcount_adj;
+}