On Thu, Jun 16, 2016 at 06:22:14PM -0700, Darrick J. Wong wrote:
> Create rmap update intent/done log items to record redo information in
> the log. Because we need to roll transactions between updating the
> bmbt mapping and updating the reverse mapping, we also have to track
> the status of the metadata updates that will be recorded in the
> post-roll transactions, just in case we crash before committing the
> final transaction. This mechanism enables log recovery to finish what
> was already started.
>
> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> ---
A couple nits below, otherwise looks good:
Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>
> fs/xfs/Makefile | 1
> fs/xfs/libxfs/xfs_log_format.h | 67 ++++++
> fs/xfs/libxfs/xfs_rmap_btree.h | 19 ++
> fs/xfs/xfs_rmap_item.c | 459 ++++++++++++++++++++++++++++++++++++++++
> fs/xfs/xfs_rmap_item.h | 100 +++++++++
> fs/xfs/xfs_super.c | 21 ++
> 6 files changed, 665 insertions(+), 2 deletions(-)
> create mode 100644 fs/xfs/xfs_rmap_item.c
> create mode 100644 fs/xfs/xfs_rmap_item.h
>
>
> diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
> index 2de8c20..8ae0a10 100644
> --- a/fs/xfs/Makefile
> +++ b/fs/xfs/Makefile
> @@ -104,6 +104,7 @@ xfs-y += xfs_log.o \
> xfs_extfree_item.o \
> xfs_icreate_item.o \
> xfs_inode_item.o \
> + xfs_rmap_item.o \
> xfs_log_recover.o \
> xfs_trans_ail.o \
> xfs_trans_buf.o \
> diff --git a/fs/xfs/libxfs/xfs_log_format.h b/fs/xfs/libxfs/xfs_log_format.h
> index e5baba3..b9627b7 100644
> --- a/fs/xfs/libxfs/xfs_log_format.h
> +++ b/fs/xfs/libxfs/xfs_log_format.h
> @@ -110,7 +110,9 @@ static inline uint xlog_get_cycle(char *ptr)
> #define XLOG_REG_TYPE_COMMIT 18
> #define XLOG_REG_TYPE_TRANSHDR 19
> #define XLOG_REG_TYPE_ICREATE 20
> -#define XLOG_REG_TYPE_MAX 20
> +#define XLOG_REG_TYPE_RUI_FORMAT 21
> +#define XLOG_REG_TYPE_RUD_FORMAT 22
> +#define XLOG_REG_TYPE_MAX 22
>
> /*
> * Flags to log operation header
> @@ -227,6 +229,8 @@ typedef struct xfs_trans_header {
> #define XFS_LI_DQUOT 0x123d
> #define XFS_LI_QUOTAOFF 0x123e
> #define XFS_LI_ICREATE 0x123f
> +#define XFS_LI_RUI 0x1240 /* rmap update intent */
> +#define XFS_LI_RUD 0x1241
>
> #define XFS_LI_TYPE_DESC \
> { XFS_LI_EFI, "XFS_LI_EFI" }, \
> @@ -236,7 +240,9 @@ typedef struct xfs_trans_header {
> { XFS_LI_BUF, "XFS_LI_BUF" }, \
> { XFS_LI_DQUOT, "XFS_LI_DQUOT" }, \
> { XFS_LI_QUOTAOFF, "XFS_LI_QUOTAOFF" }, \
> - { XFS_LI_ICREATE, "XFS_LI_ICREATE" }
> + { XFS_LI_ICREATE, "XFS_LI_ICREATE" }, \
> + { XFS_LI_RUI, "XFS_LI_RUI" }, \
> + { XFS_LI_RUD, "XFS_LI_RUD" }
>
> /*
> * Inode Log Item Format definitions.
> @@ -604,6 +610,63 @@ typedef struct xfs_efd_log_format_64 {
> } xfs_efd_log_format_64_t;
>
> /*
> + * RUI/RUD (reverse mapping) log format definitions
> + */
> +struct xfs_map_extent {
> + __uint64_t me_owner;
> + __uint64_t me_startblock;
> + __uint64_t me_startoff;
> + __uint32_t me_len;
> + __uint32_t me_flags;
> +};
> +
> +/* rmap me_flags: upper bits are flags, lower byte is type code */
> +#define XFS_RMAP_EXTENT_MAP 1
> +#define XFS_RMAP_EXTENT_MAP_SHARED 2
> +#define XFS_RMAP_EXTENT_UNMAP 3
> +#define XFS_RMAP_EXTENT_UNMAP_SHARED 4
> +#define XFS_RMAP_EXTENT_CONVERT 5
> +#define XFS_RMAP_EXTENT_CONVERT_SHARED 6
> +#define XFS_RMAP_EXTENT_ALLOC 7
> +#define XFS_RMAP_EXTENT_FREE 8
> +#define XFS_RMAP_EXTENT_TYPE_MASK 0xFF
I assume all of the _SHARED stuff defined here and throughout is not
used until reflink.. (not that big of a deal if it's a PITA to remove).
> +
> +#define XFS_RMAP_EXTENT_ATTR_FORK (1U << 31)
> +#define XFS_RMAP_EXTENT_BMBT_BLOCK (1U << 30)
> +#define XFS_RMAP_EXTENT_UNWRITTEN (1U << 29)
> +
> +#define XFS_RMAP_EXTENT_FLAGS (XFS_RMAP_EXTENT_TYPE_MASK | \
> + XFS_RMAP_EXTENT_ATTR_FORK | \
> + XFS_RMAP_EXTENT_BMBT_BLOCK | \
> + XFS_RMAP_EXTENT_UNWRITTEN)
> +
> +/*
> + * This is the structure used to lay out an rui log item in the
> + * log. The rui_extents field is a variable size array whose
> + * size is given by rui_nextents.
> + */
> +struct xfs_rui_log_format {
> + __uint16_t rui_type; /* rui log item type */
> + __uint16_t rui_size; /* size of this item */
> + __uint32_t rui_nextents; /* # extents to free */
> + __uint64_t rui_id; /* rui identifier */
> + struct xfs_map_extent rui_extents[1]; /* array of extents to rmap */
> +};
> +
> +/*
> + * This is the structure used to lay out an rud log item in the
> + * log. The rud_extents array is a variable size array whose
> + * size is given by rud_nextents;
> + */
> +struct xfs_rud_log_format {
> + __uint16_t rud_type; /* rud log item type */
> + __uint16_t rud_size; /* size of this item */
> + __uint32_t rud_nextents; /* # of extents freed */
> + __uint64_t rud_rui_id; /* id of corresponding rui */
> + struct xfs_map_extent rud_extents[1]; /* array of extents rmapped */
> +};
> +
> +/*
> * Dquot Log format definitions.
> *
> * The first two fields must be the type and size fitting into
...
> diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c
> new file mode 100644
> index 0000000..91a3b2c
> --- /dev/null
> +++ b/fs/xfs/xfs_rmap_item.c
> @@ -0,0 +1,459 @@
...
> +/*
> + * Copy an RUI format buffer from the given buf, and into the destination
> + * RUI format structure. The RUI/RUD items were designed not to need any
> + * special alignment handling.
> + */
> +int
> +xfs_rui_copy_format(
> + struct xfs_log_iovec *buf,
> + struct xfs_rui_log_format *dst_rui_fmt)
> +{
> + struct xfs_rui_log_format *src_rui_fmt;
> + uint len;
> +
> + src_rui_fmt = buf->i_addr;
> + len = sizeof(struct xfs_rui_log_format) +
> + (src_rui_fmt->rui_nextents - 1) *
> + sizeof(struct xfs_map_extent);
> +
> + if (buf->i_len == len) {
> + memcpy((char *)dst_rui_fmt, (char *)src_rui_fmt, len);
> + return 0;
> + }
> + return -EFSCORRUPTED;
I'd switch this around since we don't have the mess that
xfs_efi_copy_format() has to deal with. E.g.,
if (buf->i_len != len)
return -EFSCORRUPTED;
memcpy(..);
return 0;
Brian
> +}
> +
> +/*
> + * Freeing the RUI requires that we remove it from the AIL if it has already
> + * been placed there. However, the RUI may not yet have been placed in the AIL
> + * when called by xfs_rui_release() from RUD processing due to the ordering of
> + * committed vs unpin operations in bulk insert operations. Hence the reference
> + * count to ensure only the last caller frees the RUI.
> + */
> +void
> +xfs_rui_release(
> + struct xfs_rui_log_item *ruip)
> +{
> + if (atomic_dec_and_test(&ruip->rui_refcount)) {
> + xfs_trans_ail_remove(&ruip->rui_item, SHUTDOWN_LOG_IO_ERROR);
> + xfs_rui_item_free(ruip);
> + }
> +}
> +
> +static inline struct xfs_rud_log_item *RUD_ITEM(struct xfs_log_item *lip)
> +{
> + return container_of(lip, struct xfs_rud_log_item, rud_item);
> +}
> +
> +STATIC void
> +xfs_rud_item_free(struct xfs_rud_log_item *rudp)
> +{
> + if (rudp->rud_format.rud_nextents > XFS_RUD_MAX_FAST_EXTENTS)
> + kmem_free(rudp);
> + else
> + kmem_zone_free(xfs_rud_zone, rudp);
> +}
> +
> +/*
> + * This returns the number of iovecs needed to log the given rud item.
> + * We only need 1 iovec for an rud item. It just logs the rud_log_format
> + * structure.
> + */
> +static inline int
> +xfs_rud_item_sizeof(
> + struct xfs_rud_log_item *rudp)
> +{
> + return sizeof(struct xfs_rud_log_format) +
> + (rudp->rud_format.rud_nextents - 1) *
> + sizeof(struct xfs_map_extent);
> +}
> +
> +STATIC void
> +xfs_rud_item_size(
> + struct xfs_log_item *lip,
> + int *nvecs,
> + int *nbytes)
> +{
> + *nvecs += 1;
> + *nbytes += xfs_rud_item_sizeof(RUD_ITEM(lip));
> +}
> +
> +/*
> + * This is called to fill in the vector of log iovecs for the
> + * given rud log item. We use only 1 iovec, and we point that
> + * at the rud_log_format structure embedded in the rud item.
> + * It is at this point that we assert that all of the extent
> + * slots in the rud item have been filled.
> + */
> +STATIC void
> +xfs_rud_item_format(
> + struct xfs_log_item *lip,
> + struct xfs_log_vec *lv)
> +{
> + struct xfs_rud_log_item *rudp = RUD_ITEM(lip);
> + struct xfs_log_iovec *vecp = NULL;
> +
> + ASSERT(rudp->rud_next_extent == rudp->rud_format.rud_nextents);
> +
> + rudp->rud_format.rud_type = XFS_LI_RUD;
> + rudp->rud_format.rud_size = 1;
> +
> + xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_RUD_FORMAT, &rudp->rud_format,
> + xfs_rud_item_sizeof(rudp));
> +}
> +
> +/*
> + * Pinning has no meaning for an rud item, so just return.
> + */
> +STATIC void
> +xfs_rud_item_pin(
> + struct xfs_log_item *lip)
> +{
> +}
> +
> +/*
> + * Since pinning has no meaning for an rud item, unpinning does
> + * not either.
> + */
> +STATIC void
> +xfs_rud_item_unpin(
> + struct xfs_log_item *lip,
> + int remove)
> +{
> +}
> +
> +/*
> + * There isn't much you can do to push on an rud item. It is simply stuck
> + * waiting for the log to be flushed to disk.
> + */
> +STATIC uint
> +xfs_rud_item_push(
> + struct xfs_log_item *lip,
> + struct list_head *buffer_list)
> +{
> + return XFS_ITEM_PINNED;
> +}
> +
> +/*
> + * The RUD is either committed or aborted if the transaction is cancelled. If
> + * the transaction is cancelled, drop our reference to the RUI and free the
> + * RUD.
> + */
> +STATIC void
> +xfs_rud_item_unlock(
> + struct xfs_log_item *lip)
> +{
> + struct xfs_rud_log_item *rudp = RUD_ITEM(lip);
> +
> + if (lip->li_flags & XFS_LI_ABORTED) {
> + xfs_rui_release(rudp->rud_ruip);
> + xfs_rud_item_free(rudp);
> + }
> +}
> +
> +/*
> + * When the rud item is committed to disk, all we need to do is delete our
> + * reference to our partner rui item and then free ourselves. Since we're
> + * freeing ourselves we must return -1 to keep the transaction code from
> + * further referencing this item.
> + */
> +STATIC xfs_lsn_t
> +xfs_rud_item_committed(
> + struct xfs_log_item *lip,
> + xfs_lsn_t lsn)
> +{
> + struct xfs_rud_log_item *rudp = RUD_ITEM(lip);
> +
> + /*
> + * Drop the RUI reference regardless of whether the RUD has been
> + * aborted. Once the RUD transaction is constructed, it is the sole
> + * responsibility of the RUD to release the RUI (even if the RUI is
> + * aborted due to log I/O error).
> + */
> + xfs_rui_release(rudp->rud_ruip);
> + xfs_rud_item_free(rudp);
> +
> + return (xfs_lsn_t)-1;
> +}
> +
> +/*
> + * The RUD dependency tracking op doesn't do squat. It can't because
> + * it doesn't know where the free extent is coming from. The dependency
> + * tracking has to be handled by the "enclosing" metadata object. For
> + * example, for inodes, the inode is locked throughout the extent freeing
> + * so the dependency should be recorded there.
> + */
> +STATIC void
> +xfs_rud_item_committing(
> + struct xfs_log_item *lip,
> + xfs_lsn_t lsn)
> +{
> +}
> +
> +/*
> + * This is the ops vector shared by all rud log items.
> + */
> +static const struct xfs_item_ops xfs_rud_item_ops = {
> + .iop_size = xfs_rud_item_size,
> + .iop_format = xfs_rud_item_format,
> + .iop_pin = xfs_rud_item_pin,
> + .iop_unpin = xfs_rud_item_unpin,
> + .iop_unlock = xfs_rud_item_unlock,
> + .iop_committed = xfs_rud_item_committed,
> + .iop_push = xfs_rud_item_push,
> + .iop_committing = xfs_rud_item_committing,
> +};
> +
> +/*
> + * Allocate and initialize an rud item with the given number of extents.
> + */
> +struct xfs_rud_log_item *
> +xfs_rud_init(
> + struct xfs_mount *mp,
> + struct xfs_rui_log_item *ruip,
> + uint nextents)
> +
> +{
> + struct xfs_rud_log_item *rudp;
> + uint size;
> +
> + ASSERT(nextents > 0);
> + if (nextents > XFS_RUD_MAX_FAST_EXTENTS) {
> + size = (uint)(sizeof(struct xfs_rud_log_item) +
> + ((nextents - 1) * sizeof(struct xfs_map_extent)));
> + rudp = kmem_zalloc(size, KM_SLEEP);
> + } else {
> + rudp = kmem_zone_zalloc(xfs_rud_zone, KM_SLEEP);
> + }
> +
> + xfs_log_item_init(mp, &rudp->rud_item, XFS_LI_RUD, &xfs_rud_item_ops);
> + rudp->rud_ruip = ruip;
> + rudp->rud_format.rud_nextents = nextents;
> + rudp->rud_format.rud_rui_id = ruip->rui_format.rui_id;
> +
> + return rudp;
> +}
> diff --git a/fs/xfs/xfs_rmap_item.h b/fs/xfs/xfs_rmap_item.h
> new file mode 100644
> index 0000000..bd36ab5
> --- /dev/null
> +++ b/fs/xfs/xfs_rmap_item.h
> @@ -0,0 +1,100 @@
> +/*
> + * Copyright (C) 2016 Oracle. All Rights Reserved.
> + *
> + * Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> + *
> + * 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; either version 2
> + * of the License, or (at your option) any later version.
> + *
> + * 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.
> + */
> +#ifndef __XFS_RMAP_ITEM_H__
> +#define __XFS_RMAP_ITEM_H__
> +
> +/*
> + * There are (currently) three pairs of rmap btree redo item types: map, unmap,
> + * and convert. The common abbreviations for these are RUI (rmap update
> + * intent) and RUD (rmap update done). The redo item type is encoded in the
> + * flags field of each xfs_map_extent.
> + *
> + * *I items should be recorded in the *first* of a series of rolled
> + * transactions, and the *D items should be recorded in the same transaction
> + * that records the associated rmapbt updates. Typically, the first
> + * transaction will record a bmbt update, followed by some number of
> + * transactions containing rmapbt updates, and finally transactions with any
> + * bnobt/cntbt updates.
> + *
> + * Should the system crash after the commit of the first transaction but
> + * before the commit of the final transaction in a series, log recovery will
> + * use the redo information recorded by the intent items to replay the
> + * (rmapbt/bnobt/cntbt) metadata updates in the non-first transaction.
> + */
> +
> +/* kernel only RUI/RUD definitions */
> +
> +struct xfs_mount;
> +struct kmem_zone;
> +
> +/*
> + * Max number of extents in fast allocation path.
> + */
> +#define XFS_RUI_MAX_FAST_EXTENTS 16
> +
> +/*
> + * Define RUI flag bits. Manipulated by set/clear/test_bit operators.
> + */
> +#define XFS_RUI_RECOVERED 1
> +
> +/*
> + * This is the "rmap update intent" log item. It is used to log the fact that
> + * some reverse mappings need to change. It is used in conjunction with the
> + * "rmap update done" log item described below.
> + *
> + * These log items follow the same rules as struct xfs_efi_log_item; see the
> + * comments about that structure (in xfs_extfree_item.h) for more details.
> + */
> +struct xfs_rui_log_item {
> + struct xfs_log_item rui_item;
> + atomic_t rui_refcount;
> + atomic_t rui_next_extent;
> + unsigned long rui_flags; /* misc flags */
> + struct xfs_rui_log_format rui_format;
> +};
> +
> +/*
> + * This is the "rmap update done" log item. It is used to log the fact that
> + * some rmapbt updates mentioned in an earlier rui item have been performed.
> + */
> +struct xfs_rud_log_item {
> + struct xfs_log_item rud_item;
> + struct xfs_rui_log_item *rud_ruip;
> + uint rud_next_extent;
> + struct xfs_rud_log_format rud_format;
> +};
> +
> +/*
> + * Max number of extents in fast allocation path.
> + */
> +#define XFS_RUD_MAX_FAST_EXTENTS 16
> +
> +extern struct kmem_zone *xfs_rui_zone;
> +extern struct kmem_zone *xfs_rud_zone;
> +
> +struct xfs_rui_log_item *xfs_rui_init(struct xfs_mount *, uint);
> +struct xfs_rud_log_item *xfs_rud_init(struct xfs_mount *,
> + struct xfs_rui_log_item *, uint);
> +int xfs_rui_copy_format(struct xfs_log_iovec *buf,
> + struct xfs_rui_log_format *dst_rui_fmt);
> +void xfs_rui_item_free(struct xfs_rui_log_item *);
> +void xfs_rui_release(struct xfs_rui_log_item *);
> +
> +#endif /* __XFS_RMAP_ITEM_H__ */
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 1575849..a8300e4 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -47,6 +47,7 @@
> #include "xfs_sysfs.h"
> #include "xfs_ondisk.h"
> #include "xfs_defer.h"
> +#include "xfs_rmap_item.h"
>
> #include <linux/namei.h>
> #include <linux/init.h>
> @@ -1762,8 +1763,26 @@ xfs_init_zones(void)
> if (!xfs_icreate_zone)
> goto out_destroy_ili_zone;
>
> + xfs_rud_zone = kmem_zone_init((sizeof(struct xfs_rud_log_item) +
> + ((XFS_RUD_MAX_FAST_EXTENTS - 1) *
> + sizeof(struct xfs_map_extent))),
> + "xfs_rud_item");
> + if (!xfs_rud_zone)
> + goto out_destroy_icreate_zone;
> +
> + xfs_rui_zone = kmem_zone_init((sizeof(struct xfs_rui_log_item) +
> + ((XFS_RUI_MAX_FAST_EXTENTS - 1) *
> + sizeof(struct xfs_map_extent))),
> + "xfs_rui_item");
> + if (!xfs_rui_zone)
> + goto out_destroy_rud_zone;
> +
> return 0;
>
> + out_destroy_rud_zone:
> + kmem_zone_destroy(xfs_rud_zone);
> + out_destroy_icreate_zone:
> + kmem_zone_destroy(xfs_icreate_zone);
> out_destroy_ili_zone:
> kmem_zone_destroy(xfs_ili_zone);
> out_destroy_inode_zone:
> @@ -1802,6 +1821,8 @@ xfs_destroy_zones(void)
> * destroy caches.
> */
> rcu_barrier();
> + kmem_zone_destroy(xfs_rui_zone);
> + kmem_zone_destroy(xfs_rud_zone);
> kmem_zone_destroy(xfs_icreate_zone);
> kmem_zone_destroy(xfs_ili_zone);
> kmem_zone_destroy(xfs_inode_zone);
>
> _______________________________________________
> xfs mailing list
> xfs@xxxxxxxxxxx
> http://oss.sgi.com/mailman/listinfo/xfs
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