[PATCH 6/9] xfs: use vfs inode nlink field everywhere

Dave Chinner
2016-02-08T04:24:36Z

From: Dave Chinner <dchinner@redhat.com>

The Vfs tracks the inodenlink just like the xfs_icdinode. We can
remove the variable from the icdinode and use the vfs inode variable
everywhere, reducing the size of the xfs_icdinode by a further 4
bytes.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/libxfs/xfs_inode_buf.c | 6 ++--
fs/xfs/libxfs/xfs_inode_buf.h | 1 -
fs/xfs/xfs_icache.c | 2 ++
fs/xfs/xfs_inode.c | 77 ++++++++++++++++++++-----------------------
fs/xfs/xfs_inode.h | 2 --
fs/xfs/xfs_inode_item.c | 2 +-
fs/xfs/xfs_iops.c | 3 +-
fs/xfs/xfs_itable.c | 2 +-
fs/xfs/xfs_log_recover.c | 2 +-
9 files changed, 45 insertions(+), 52 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c
index 8a1b460..0dcaa9a 100644
--- a/fs/xfs/libxfs/xfs_inode_buf.c
+++ b/fs/xfs/libxfs/xfs_inode_buf.c
@@ -210,12 +210,12 @@ xfs_inode_from_disk(
* minimum inode version format we support in the rest of the code.
*/
if (to->di_version == 1) {
- to->di_nlink = be16_to_cpu(from->di_onlink);
+ set_nlink(inode, be16_to_cpu(from->di_onlink));
to->di_projid_lo = 0;
to->di_projid_hi = 0;
to->di_version = 2;
} else {
- to->di_nlink = be32_to_cpu(from->di_nlink);
+ set_nlink(inode, be32_to_cpu(from->di_nlink));
to->di_projid_lo = be16_to_cpu(from->di_projid_lo);
to->di_projid_hi = be16_to_cpu(from->di_projid_hi);
}
@@ -275,7 +275,6 @@ xfs_inode_to_disk(
to->di_format = from->di_format;
to->di_uid = cpu_to_be32(from->di_uid);
to->di_gid = cpu_to_be32(from->di_gid);
- to->di_nlink = cpu_to_be32(from->di_nlink);
to->di_projid_lo = cpu_to_be16(from->di_projid_lo);
to->di_projid_hi = cpu_to_be16(from->di_projid_hi);

@@ -286,6 +285,7 @@ xfs_inode_to_disk(
to->di_mtime.t_nsec = cpu_to_be32(inode->i_mtime.tv_nsec);
to->di_ctime.t_sec = cpu_to_be32(inode->i_ctime.tv_sec);
to->di_ctime.t_nsec = cpu_to_be32(inode->i_ctime.tv_nsec);
+ to->di_nlink = cpu_to_be32(inode->i_nlink);

to->di_size = cpu_to_be64(from->di_size);
to->di_nblocks = cpu_to_be64(from->di_nblocks);
diff --git a/fs/xfs/libxfs/xfs_inode_buf.h b/fs/xfs/libxfs/xfs_inode_buf.h
index 73ba1d8..320b723 100644
--- a/fs/xfs/libxfs/xfs_inode_buf.h
+++ b/fs/xfs/libxfs/xfs_inode_buf.h
@@ -34,7 +34,6 @@ struct xfs_icdinode {
__uint16_t di_flushiter; /* incremented on flush */
__uint32_t di_uid; /* owner's user id */
__uint32_t di_gid; /* owner's group id */
- __uint32_t di_nlink; /* number of links to file */
__uint16_t di_projid_lo; /* lower part of owner's project id */
__uint16_t di_projid_hi; /* higher part of owner's project id */
xfs_fsize_t di_size; /* number of bytes in file */
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 9ca28655..4c184f7 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -148,9 +148,11 @@ xfs_reinit_inode(
struct inode *inode)
{
int error;
+ uint32_t nlink = inode->i_nlink;

error = inode_init_always(mp->m_super, inode);

+ set_nlink(inode, nlink);
return error;
}

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 7d9c514..ed8e3d2 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -57,9 +57,9 @@ kmem_zone_t *xfs_inode_zone;
*/
#define XFS_ITRUNC_MAX_EXTENTS 2

-STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *);
-
-STATIC int xfs_iunlink_remove(xfs_trans_t *, xfs_inode_t *);
+STATIC int xfs_iflush_int(struct xfs_inode *, struct xfs_buf *);
+STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *, bool);
+STATIC int xfs_iunlink_remove(struct xfs_trans *, struct xfs_inode *);

/*
* helper function to extract extent size hint from inode
@@ -803,7 +803,7 @@ xfs_ialloc(
ip->i_d.di_version = 2;

ip->i_d.di_mode = mode;
- ip->i_d.di_nlink = nlink;
+ set_nlink(inode, nlink);
ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
xfs_set_projid(ip, prid);
@@ -1086,35 +1086,24 @@ xfs_dir_ialloc(
}

/*
- * Decrement the link count on an inode & log the change.
- * If this causes the link count to go to zero, initiate the
- * logging activity required to truncate a file.
+ * Decrement the link count on an inode & log the change. If this causes the
+ * link count to go to zero, move the inode to AGI unlinked list so that it can
+ * be freed when the last active reference goes away via xfs_inactive().
*/
int /* error */
xfs_droplink(
xfs_trans_t *tp,
xfs_inode_t *ip)
{
- int error;
-
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);

- ASSERT (ip->i_d.di_nlink > 0);
- ip->i_d.di_nlink--;
drop_nlink(VFS_I(ip));
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);

- error = 0;
- if (ip->i_d.di_nlink == 0) {
- /*
- * We're dropping the last link to this file.
- * Move the on-disk inode to the AGI unlinked list.
- * From xfs_inactive() we will pull the inode from
- * the list and free it.
- */
- error = xfs_iunlink(tp, ip);
- }
- return error;
+ if (VFS_I(ip)->i_nlink)
+ return 0;
+
+ return xfs_iunlink(tp, ip, false);
}

/*
@@ -1128,8 +1117,6 @@ xfs_bumplink(
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);

ASSERT(ip->i_d.di_version > 1);
- ASSERT(ip->i_d.di_nlink > 0 || (VFS_I(ip)->i_state & I_LINKABLE));
- ip->i_d.di_nlink++;
inc_nlink(VFS_I(ip));
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
return 0;
@@ -1387,8 +1374,7 @@ xfs_create_tmpfile(
*/
xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);

- ip->i_d.di_nlink--;
- error = xfs_iunlink(tp, ip);
+ error = xfs_iunlink(tp, ip, true);
if (error)
goto out_trans_cancel;

@@ -1486,7 +1472,10 @@ xfs_link(

xfs_bmap_init(&free_list, &first_block);

- if (sip->i_d.di_nlink == 0) {
+ /*
+ * Handle initial link state of O_TMPFILE inode
+ */
+ if (VFS_I(sip)->i_nlink == 0) {
error = xfs_iunlink_remove(tp, sip);
if (error)
goto error_return;
@@ -1673,7 +1662,7 @@ xfs_release(
}
}

- if (ip->i_d.di_nlink == 0)
+ if (VFS_I(ip)->i_nlink == 0)
return 0;

if (xfs_can_free_eofblocks(ip, false)) {
@@ -1889,7 +1878,7 @@ xfs_inactive(
if (mp->m_flags & XFS_MOUNT_RDONLY)
return;

- if (ip->i_d.di_nlink != 0) {
+ if (VFS_I(ip)->i_nlink != 0) {
/*
* force is true because we are evicting an inode from the
* cache. Post-eof blocks must be freed, lest we end up with
@@ -1946,14 +1935,20 @@ xfs_inactive(
}

/*
- * This is called when the inode's link count goes to 0.
- * We place the on-disk inode on a list in the AGI. It
- * will be pulled from this list when the inode is freed.
+ * This is called when the inode's link count goes to 0 or we are creating a
+ * tmpfile via O_TMPFILE. In the case of a tmpfile, @ignore_linkcount will be
+ * set to true as the link count is dropped to zero by the VFS after we've
+ * created the file successfully, so we have to add it to the unlinked list
+ * while the link count is non-zero.
+ *
+ * We place the on-disk inode on a list in the AGI. It will be pulled from this
+ * list when the inode is freed.
*/
-int
+STATIC int
xfs_iunlink(
- xfs_trans_t *tp,
- xfs_inode_t *ip)
+ struct xfs_trans *tp,
+ struct xfs_inode *ip,
+ bool ignore_linkcount)
{
xfs_mount_t *mp;
xfs_agi_t *agi;
@@ -1965,7 +1960,7 @@ xfs_iunlink(
int offset;
int error;

- ASSERT(ip->i_d.di_nlink == 0);
+ ASSERT(VFS_I(ip)->i_nlink == 0 || ignore_linkcount);
ASSERT(ip->i_d.di_mode != 0);

mp = tp->t_mountp;
@@ -2406,7 +2401,7 @@ xfs_ifree(
struct xfs_icluster xic = { 0 };

ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
- ASSERT(ip->i_d.di_nlink == 0);
+ ASSERT(VFS_I(ip)->i_nlink == 0);
ASSERT(ip->i_d.di_nextents == 0);
ASSERT(ip->i_d.di_anextents == 0);
ASSERT(ip->i_d.di_size == 0 || !S_ISREG(ip->i_d.di_mode));
@@ -2574,8 +2569,8 @@ xfs_remove(
* If we're removing a directory perform some additional validation.
*/
if (is_dir) {
- ASSERT(ip->i_d.di_nlink >= 2);
- if (ip->i_d.di_nlink != 2) {
+ ASSERT(VFS_I(ip)->i_nlink >= 2);
+ if (VFS_I(ip)->i_nlink != 2) {
error = -ENOTEMPTY;
goto out_trans_cancel;
}
@@ -3031,7 +3026,7 @@ xfs_rename(
* Make sure target dir is empty.
*/
if (!(xfs_dir_isempty(target_ip)) ||
- (target_ip->i_d.di_nlink > 2)) {
+ (VFS_I(target_ip)->i_nlink > 2)) {
error = -EEXIST;
goto out_trans_cancel;
}
@@ -3138,7 +3133,7 @@ xfs_rename(
* intermediate state on disk.
*/
if (wip) {
- ASSERT(VFS_I(wip)->i_nlink == 0 && wip->i_d.di_nlink == 0);
+ ASSERT(VFS_I(wip)->i_nlink == 0);
error = xfs_bumplink(tp, wip);
if (error)
goto out_bmap_cancel;
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 57c5947..4eaf425 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -405,8 +405,6 @@ int xfs_ifree(struct xfs_trans *, xfs_inode_t *,
struct xfs_bmap_free *);
int xfs_itruncate_extents(struct xfs_trans **, struct xfs_inode *,
int, xfs_fsize_t);
-int xfs_iunlink(struct xfs_trans *, xfs_inode_t *);
-
void xfs_iext_realloc(xfs_inode_t *, int, int);

void xfs_iunpin_wait(xfs_inode_t *);
diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
index 1e5ecbc..193e0bd 100644
--- a/fs/xfs/xfs_inode_item.c
+++ b/fs/xfs/xfs_inode_item.c
@@ -338,7 +338,6 @@ xfs_inode_to_log_dinode(
to->di_format = from->di_format;
to->di_uid = from->di_uid;
to->di_gid = from->di_gid;
- to->di_nlink = from->di_nlink;
to->di_projid_lo = from->di_projid_lo;
to->di_projid_hi = from->di_projid_hi;

@@ -350,6 +349,7 @@ xfs_inode_to_log_dinode(
to->di_mtime.t_nsec = inode->i_mtime.tv_nsec;
to->di_ctime.t_sec = inode->i_ctime.tv_sec;
to->di_ctime.t_nsec = inode->i_ctime.tv_nsec;
+ to->di_nlink = inode->i_nlink;

to->di_size = from->di_size;
to->di_nblocks = from->di_nblocks;
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index cd27c6d..8982e56 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -460,7 +460,7 @@ xfs_vn_getattr(
stat->size = XFS_ISIZE(ip);
stat->dev = inode->i_sb->s_dev;
stat->mode = ip->i_d.di_mode;
- stat->nlink = ip->i_d.di_nlink;
+ stat->nlink = inode->i_nlink;
stat->uid = inode->i_uid;
stat->gid = inode->i_gid;
stat->ino = ip->i_ino;
@@ -1216,7 +1216,6 @@ xfs_setup_inode(
hlist_add_fake(&inode->i_hash);

inode->i_mode = ip->i_d.di_mode;
- set_nlink(inode, ip->i_d.di_nlink);
inode->i_uid = xfs_uid_to_kuid(ip->i_d.di_uid);
inode->i_gid = xfs_gid_to_kgid(ip->i_d.di_gid);

diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index 2acda42..cfb6527 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -85,7 +85,6 @@ xfs_bulkstat_one_int(
/* xfs_iget returns the following without needing
* further change.
*/
- buf->bs_nlink = dic->di_nlink;
buf->bs_projid_lo = dic->di_projid_lo;
buf->bs_projid_hi = dic->di_projid_hi;
buf->bs_ino = ino;
@@ -94,6 +93,7 @@ xfs_bulkstat_one_int(
buf->bs_gid = dic->di_gid;
buf->bs_size = dic->di_size;

+ buf->bs_nlink = inode->i_nlink;
buf->bs_atime.tv_sec = inode->i_atime.tv_sec;
buf->bs_atime.tv_nsec = inode->i_atime.tv_nsec;
buf->bs_mtime.tv_sec = inode->i_mtime.tv_sec;
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 97bcfc8..678fe6e 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -4342,7 +4342,7 @@ xlog_recover_process_one_iunlink(
if (error)
goto fail_iput;

- ASSERT(ip->i_d.di_nlink == 0);
+ ASSERT(VFS_I(ip)->i_nlink == 0);
ASSERT(ip->i_d.di_mode != 0);

/* setup for the next pass */
--
2.5.0