This cleans up a number of bits of code mostly based in glops.c.
A couple of simple functions have been merged into the callers
to make it more obvious what is going on, the mysterious raising
of i_writecount around the truncate_inode_pages() call has been
removed. The meta_go_* operations have been renamed rgrp_go_*
since that is the only lock type that they are used with.

The unused argument of gfs2_read_sb has been removed. Also
a bug has been fixed where a check for the rindex inode was
in the wrong callback. More comments are added, and the
debugging code is improved too.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index f34bc70..bf23a62 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -76,29 +76,7 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
}

/**
- * gfs2_pte_inval - Sync and invalidate all PTEs associated with a glock
- * @gl: the glock
- *
- */
-
-static void gfs2_pte_inval(struct gfs2_glock *gl)
-{
- struct gfs2_inode *ip;
- struct inode *inode;
-
- ip = gl->gl_object;
- inode = &ip->i_inode;
- if (!ip || !S_ISREG(inode->i_mode))
- return;
-
- unmap_shared_mapping_range(inode->i_mapping, 0, 0);
- if (test_bit(GIF_SW_PAGED, &ip->i_flags))
- set_bit(GLF_DIRTY, &gl->gl_flags);
-
-}
-
-/**
- * meta_go_sync - sync out the metadata for this glock
+ * rgrp_go_sync - sync out the metadata for this glock
* @gl: the glock
*
* Called when demoting or unlocking an EX glock. We must flush
@@ -106,36 +84,42 @@ static void gfs2_pte_inval(struct gfs2_glock *gl)
* not return to caller to demote/unlock the glock until I/O is complete.
*/

-static void meta_go_sync(struct gfs2_glock *gl)
+static void rgrp_go_sync(struct gfs2_glock *gl)
{
- if (gl->gl_state != LM_ST_EXCLUSIVE)
+ struct address_space *metamapping = gl->gl_aspace->i_mapping;
+ int error;
+
+ if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
return;
+ BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);

- if (test_and_clear_bit(GLF_DIRTY, &gl->gl_flags)) {
- gfs2_log_flush(gl->gl_sbd, gl);
- gfs2_meta_sync(gl);
- gfs2_ail_empty_gl(gl);
- }
+ gfs2_log_flush(gl->gl_sbd, gl);
+ filemap_fdatawrite(metamapping);
+ error = filemap_fdatawait(metamapping);
+ mapping_set_error(metamapping, error);
+ gfs2_ail_empty_gl(gl);
}

/**
- * meta_go_inval - invalidate the metadata for this glock
+ * rgrp_go_inval - invalidate the metadata for this glock
* @gl: the glock
* @flags:
*
+ * We never used LM_ST_DEFERRED with resource groups, so that we
+ * should always see the metadata flag set here.
+ *
*/

-static void meta_go_inval(struct gfs2_glock *gl, int flags)
+static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
{
- if (!(flags & DIO_METADATA))
- return;
+ struct address_space *mapping = gl->gl_aspace->i_mapping;

- gfs2_meta_inval(gl);
- if (gl->gl_object == GFS2_I(gl->gl_sbd->sd_rindex))
- gl->gl_sbd->sd_rindex_uptodate = 0;
- else if (gl->gl_ops == &gfs2_rgrp_glops && gl->gl_object) {
- struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
+ BUG_ON(!(flags & DIO_METADATA));
+ gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
+ truncate_inode_pages(mapping, 0);

+ if (gl->gl_object) {
+ struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
}
}
@@ -152,48 +136,54 @@ static void inode_go_sync(struct gfs2_glock *gl)
struct address_space *metamapping = gl->gl_aspace->i_mapping;
int error;

- if (gl->gl_state != LM_ST_UNLOCKED)
- gfs2_pte_inval(gl);
- if (gl->gl_state != LM_ST_EXCLUSIVE)
- return;
-
if (ip && !S_ISREG(ip->i_inode.i_mode))
ip = NULL;
+ if (ip && test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
+ unmap_shared_mapping_range(ip->i_inode.i_mapping, 0, 0);
+ if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
+ return;

- if (test_bit(GLF_DIRTY, &gl->gl_flags)) {
- gfs2_log_flush(gl->gl_sbd, gl);
- filemap_fdatawrite(metamapping);
- if (ip) {
- struct address_space *mapping = ip->i_inode.i_mapping;
- filemap_fdatawrite(mapping);
- error = filemap_fdatawait(mapping);
- mapping_set_error(mapping, error);
- }
- error = filemap_fdatawait(metamapping);
- mapping_set_error(metamapping, error);
- clear_bit(GLF_DIRTY, &gl->gl_flags);
- gfs2_ail_empty_gl(gl);
+ BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);
+
+ gfs2_log_flush(gl->gl_sbd, gl);
+ filemap_fdatawrite(metamapping);
+ if (ip) {
+ struct address_space *mapping = ip->i_inode.i_mapping;
+ filemap_fdatawrite(mapping);
+ error = filemap_fdatawait(mapping);
+ mapping_set_error(mapping, error);
}
+ error = filemap_fdatawait(metamapping);
+ mapping_set_error(metamapping, error);
+ gfs2_ail_empty_gl(gl);
}

/**
* inode_go_inval - prepare a inode glock to be released
* @gl: the glock
* @flags:
+ *
+ * Normally we invlidate everything, but if we are moving into
+ * LM_ST_DEFERRED from LM_ST_SHARED or LM_ST_EXCLUSIVE then we
+ * can keep hold of the metadata, since it won't have changed.
*
*/

static void inode_go_inval(struct gfs2_glock *gl, int flags)
{
struct gfs2_inode *ip = gl->gl_object;
- int meta = (flags & DIO_METADATA);

- if (meta) {
- gfs2_meta_inval(gl);
+ gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
+
+ if (flags & DIO_METADATA) {
+ struct address_space *mapping = gl->gl_aspace->i_mapping;
+ truncate_inode_pages(mapping, 0);
if (ip)
set_bit(GIF_INVALID, &ip->i_flags);
}

+ if (ip == GFS2_I(gl->gl_sbd->sd_rindex))
+ gl->gl_sbd->sd_rindex_uptodate = 0;
if (ip && S_ISREG(ip->i_inode.i_mode))
truncate_inode_pages(ip->i_inode.i_mapping, 0);
}
@@ -395,7 +385,6 @@ static int trans_go_demote_ok(const struct gfs2_glock *gl)
}

const struct gfs2_glock_operations gfs2_meta_glops = {
- .go_xmote_th = meta_go_sync,
.go_type = LM_TYPE_META,
};

@@ -410,8 +399,8 @@ const struct gfs2_glock_operations gfs2_inode_glops = {
};

const struct gfs2_glock_operations gfs2_rgrp_glops = {
- .go_xmote_th = meta_go_sync,
- .go_inval = meta_go_inval,
+ .go_xmote_th = rgrp_go_sync,
+ .go_inval = rgrp_go_inval,
.go_demote_ok = rgrp_go_demote_ok,
.go_lock = rgrp_go_lock,
.go_unlock = rgrp_go_unlock,
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 870d65a..8d6f132 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -89,27 +89,6 @@ void gfs2_aspace_put(struct inode *aspace)
}

/**
- * gfs2_meta_inval - Invalidate all buffers associated with a glock
- * @gl: the glock
- *
- */
-
-void gfs2_meta_inval(struct gfs2_glock *gl)
-{
- struct gfs2_sbd *sdp = gl->gl_sbd;
- struct inode *aspace = gl->gl_aspace;
- struct address_space *mapping = gl->gl_aspace->i_mapping;
-
- gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
-
- atomic_inc(&aspace->i_writecount);
- truncate_inode_pages(mapping, 0);
- atomic_dec(&aspace->i_writecount);
-
- gfs2_assert_withdraw(sdp, !mapping->nrpages);
-}
-
-/**
* gfs2_meta_sync - Sync all buffers associated with a glock
* @gl: The glock
*
diff --git a/fs/gfs2/meta_io.h b/fs/gfs2/meta_io.h
index b1a5f36..de270c2 100644
--- a/fs/gfs2/meta_io.h
+++ b/fs/gfs2/meta_io.h
@@ -40,7 +40,6 @@ static inline void gfs2_buffer_copy_tail(struct buffer_head *to_bh,
struct inode *gfs2_aspace_get(struct gfs2_sbd *sdp);
void gfs2_aspace_put(struct inode *aspace);

-void gfs2_meta_inval(struct gfs2_glock *gl);
void gfs2_meta_sync(struct gfs2_glock *gl);

struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno);
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
index 99d726f..48ec3d5 100644
--- a/fs/gfs2/ops_file.c
+++ b/fs/gfs2/ops_file.c
@@ -355,7 +355,6 @@ static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct page *page)
if (ret)
goto out;

- set_bit(GIF_SW_PAGED, &ip->i_flags);
ret = gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE, &alloc_required);
if (ret || !alloc_required)
goto out_unlock;
@@ -396,6 +395,8 @@ static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct page *page)
goto out_unlock_page;
}
ret = gfs2_allocate_page_backing(page);
+ if (!ret)
+ set_bit(GIF_SW_PAGED, &ip->i_flags);

out_unlock_page:
unlock_page(page);
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 804ca72..51883b3 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -296,15 +296,15 @@ static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector)
__free_page(page);
return 0;
}
+
/**
* gfs2_read_sb - Read super block
* @sdp: The GFS2 superblock
- * @gl: the glock for the superblock (assumed to be held)
* @silent: Don't print message if mount fails
*
*/

-static int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
+static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
{
u32 hash_blocks, ind_blocks, leaf_blocks;
u32 tmp_blocks;
@@ -524,7 +524,7 @@ static int init_sb(struct gfs2_sbd *sdp, int silent)
return ret;
}

- ret = gfs2_read_sb(sdp, sb_gh.gh_gl, silent);
+ ret = gfs2_read_sb(sdp, silent);
if (ret) {
fs_err(sdp, "can't read superblock: %d
", ret);
goto out;

From: Steven Whitehouse <swhiteho@redhat.com>

This cleans up a number of bits of code mostly based in glops.c.
A couple of simple functions have been merged into the callers
to make it more obvious what is going on, the mysterious raising
of i_writecount around the truncate_inode_pages() call has been
removed. The meta_go_* operations have been renamed rgrp_go_*
since that is the only lock type that they are used with.

The unused argument of gfs2_read_sb has been removed. Also
a bug has been fixed where a check for the rindex inode was
in the wrong callback. More comments are added, and the
debugging code is improved too.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index f34bc70..bf23a62 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -76,29 +76,7 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
}

/**
- * gfs2_pte_inval - Sync and invalidate all PTEs associated with a glock
- * @gl: the glock
- *
- */
-
-static void gfs2_pte_inval(struct gfs2_glock *gl)
-{
- struct gfs2_inode *ip;
- struct inode *inode;
-
- ip = gl->gl_object;
- inode = &ip->i_inode;
- if (!ip || !S_ISREG(inode->i_mode))
- return;
-
- unmap_shared_mapping_range(inode->i_mapping, 0, 0);
- if (test_bit(GIF_SW_PAGED, &ip->i_flags))
- set_bit(GLF_DIRTY, &gl->gl_flags);
-
-}
-
-/**
- * meta_go_sync - sync out the metadata for this glock
+ * rgrp_go_sync - sync out the metadata for this glock
* @gl: the glock
*
* Called when demoting or unlocking an EX glock. We must flush
@@ -106,36 +84,42 @@ static void gfs2_pte_inval(struct gfs2_glock *gl)
* not return to caller to demote/unlock the glock until I/O is complete.
*/

-static void meta_go_sync(struct gfs2_glock *gl)
+static void rgrp_go_sync(struct gfs2_glock *gl)
{
- if (gl->gl_state != LM_ST_EXCLUSIVE)
+ struct address_space *metamapping = gl->gl_aspace->i_mapping;
+ int error;
+
+ if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
return;
+ BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);

- if (test_and_clear_bit(GLF_DIRTY, &gl->gl_flags)) {
- gfs2_log_flush(gl->gl_sbd, gl);
- gfs2_meta_sync(gl);
- gfs2_ail_empty_gl(gl);
- }
+ gfs2_log_flush(gl->gl_sbd, gl);
+ filemap_fdatawrite(metamapping);
+ error = filemap_fdatawait(metamapping);
+ mapping_set_error(metamapping, error);
+ gfs2_ail_empty_gl(gl);
}

/**
- * meta_go_inval - invalidate the metadata for this glock
+ * rgrp_go_inval - invalidate the metadata for this glock
* @gl: the glock
* @flags:
*
+ * We never used LM_ST_DEFERRED with resource groups, so that we
+ * should always see the metadata flag set here.
+ *
*/

-static void meta_go_inval(struct gfs2_glock *gl, int flags)
+static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
{
- if (!(flags & DIO_METADATA))
- return;
+ struct address_space *mapping = gl->gl_aspace->i_mapping;

- gfs2_meta_inval(gl);
- if (gl->gl_object == GFS2_I(gl->gl_sbd->sd_rindex))
- gl->gl_sbd->sd_rindex_uptodate = 0;
- else if (gl->gl_ops == &gfs2_rgrp_glops && gl->gl_object) {
- struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
+ BUG_ON(!(flags & DIO_METADATA));
+ gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
+ truncate_inode_pages(mapping, 0);

+ if (gl->gl_object) {
+ struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
}
}
@@ -152,48 +136,54 @@ static void inode_go_sync(struct gfs2_glock *gl)
struct address_space *metamapping = gl->gl_aspace->i_mapping;
int error;

- if (gl->gl_state != LM_ST_UNLOCKED)
- gfs2_pte_inval(gl);
- if (gl->gl_state != LM_ST_EXCLUSIVE)
- return;
-
if (ip && !S_ISREG(ip->i_inode.i_mode))
ip = NULL;
+ if (ip && test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
+ unmap_shared_mapping_range(ip->i_inode.i_mapping, 0, 0);
+ if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
+ return;

- if (test_bit(GLF_DIRTY, &gl->gl_flags)) {
- gfs2_log_flush(gl->gl_sbd, gl);
- filemap_fdatawrite(metamapping);
- if (ip) {
- struct address_space *mapping = ip->i_inode.i_mapping;
- filemap_fdatawrite(mapping);
- error = filemap_fdatawait(mapping);
- mapping_set_error(mapping, error);
- }
- error = filemap_fdatawait(metamapping);
- mapping_set_error(metamapping, error);
- clear_bit(GLF_DIRTY, &gl->gl_flags);
- gfs2_ail_empty_gl(gl);
+ BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);
+
+ gfs2_log_flush(gl->gl_sbd, gl);
+ filemap_fdatawrite(metamapping);
+ if (ip) {
+ struct address_space *mapping = ip->i_inode.i_mapping;
+ filemap_fdatawrite(mapping);
+ error = filemap_fdatawait(mapping);
+ mapping_set_error(mapping, error);
}
+ error = filemap_fdatawait(metamapping);
+ mapping_set_error(metamapping, error);
+ gfs2_ail_empty_gl(gl);
}

/**
* inode_go_inval - prepare a inode glock to be released
* @gl: the glock
* @flags:
+ *
+ * Normally we invlidate everything, but if we are moving into
+ * LM_ST_DEFERRED from LM_ST_SHARED or LM_ST_EXCLUSIVE then we
+ * can keep hold of the metadata, since it won't have changed.
*
*/

static void inode_go_inval(struct gfs2_glock *gl, int flags)
{
struct gfs2_inode *ip = gl->gl_object;
- int meta = (flags & DIO_METADATA);

- if (meta) {
- gfs2_meta_inval(gl);
+ gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
+
+ if (flags & DIO_METADATA) {
+ struct address_space *mapping = gl->gl_aspace->i_mapping;
+ truncate_inode_pages(mapping, 0);
if (ip)
set_bit(GIF_INVALID, &ip->i_flags);
}

+ if (ip == GFS2_I(gl->gl_sbd->sd_rindex))
+ gl->gl_sbd->sd_rindex_uptodate = 0;
if (ip && S_ISREG(ip->i_inode.i_mode))
truncate_inode_pages(ip->i_inode.i_mapping, 0);
}
@@ -395,7 +385,6 @@ static int trans_go_demote_ok(const struct gfs2_glock *gl)
}

const struct gfs2_glock_operations gfs2_meta_glops = {
- .go_xmote_th = meta_go_sync,
.go_type = LM_TYPE_META,
};

@@ -410,8 +399,8 @@ const struct gfs2_glock_operations gfs2_inode_glops = {
};

const struct gfs2_glock_operations gfs2_rgrp_glops = {
- .go_xmote_th = meta_go_sync,
- .go_inval = meta_go_inval,
+ .go_xmote_th = rgrp_go_sync,
+ .go_inval = rgrp_go_inval,
.go_demote_ok = rgrp_go_demote_ok,
.go_lock = rgrp_go_lock,
.go_unlock = rgrp_go_unlock,
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 870d65a..8d6f132 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -89,27 +89,6 @@ void gfs2_aspace_put(struct inode *aspace)
}

/**
- * gfs2_meta_inval - Invalidate all buffers associated with a glock
- * @gl: the glock
- *
- */
-
-void gfs2_meta_inval(struct gfs2_glock *gl)
-{
- struct gfs2_sbd *sdp = gl->gl_sbd;
- struct inode *aspace = gl->gl_aspace;
- struct address_space *mapping = gl->gl_aspace->i_mapping;
-
- gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
-
- atomic_inc(&aspace->i_writecount);
- truncate_inode_pages(mapping, 0);
- atomic_dec(&aspace->i_writecount);
-
- gfs2_assert_withdraw(sdp, !mapping->nrpages);
-}
-
-/**
* gfs2_meta_sync - Sync all buffers associated with a glock
* @gl: The glock
*
diff --git a/fs/gfs2/meta_io.h b/fs/gfs2/meta_io.h
index b1a5f36..de270c2 100644
--- a/fs/gfs2/meta_io.h
+++ b/fs/gfs2/meta_io.h
@@ -40,7 +40,6 @@ static inline void gfs2_buffer_copy_tail(struct buffer_head *to_bh,
struct inode *gfs2_aspace_get(struct gfs2_sbd *sdp);
void gfs2_aspace_put(struct inode *aspace);

-void gfs2_meta_inval(struct gfs2_glock *gl);
void gfs2_meta_sync(struct gfs2_glock *gl);

struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno);
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
index 99d726f..48ec3d5 100644
--- a/fs/gfs2/ops_file.c
+++ b/fs/gfs2/ops_file.c
@@ -355,7 +355,6 @@ static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct page *page)
if (ret)
goto out;

- set_bit(GIF_SW_PAGED, &ip->i_flags);
ret = gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE, &alloc_required);
if (ret || !alloc_required)
goto out_unlock;
@@ -396,6 +395,8 @@ static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct page *page)
goto out_unlock_page;
}
ret = gfs2_allocate_page_backing(page);
+ if (!ret)
+ set_bit(GIF_SW_PAGED, &ip->i_flags);

out_unlock_page:
unlock_page(page);
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 804ca72..51883b3 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -296,15 +296,15 @@ static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector)
__free_page(page);
return 0;
}
+
/**
* gfs2_read_sb - Read super block
* @sdp: The GFS2 superblock
- * @gl: the glock for the superblock (assumed to be held)
* @silent: Don't print message if mount fails
*
*/

-static int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
+static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
{
u32 hash_blocks, ind_blocks, leaf_blocks;
u32 tmp_blocks;
@@ -524,7 +524,7 @@ static int init_sb(struct gfs2_sbd *sdp, int silent)
return ret;
}

- ret = gfs2_read_sb(sdp, sb_gh.gh_gl, silent);
+ ret = gfs2_read_sb(sdp, silent);
if (ret) {
fs_err(sdp, "can't read superblock: %d
", ret);
goto out;
--
1.6.0.3