--- /dev/null
+From: Joel Becker <joel.becker@oracle.com>
+Subject: ocfs2: Make cached block reads the common case.
+Patch-mainline: 2.6.28
+
+ocfs2_read_blocks() currently requires the CACHED flag for cached I/O.
+However, that's the common case. Let's flip it around and provide an
+IGNORE_CACHE flag for the special users. This has the added benefit of
+cleaning up the code some (ignore_cache takes on its special meaning
+earlier in the loop).
+
+Signed-off-by: Joel Becker <joel.becker@oracle.com>
+Signed-off-by: Mark Fasheh <mfasheh@suse.com>
+---
+ fs/ocfs2/buffer_head_io.c | 19 +++++++++++--------
+ fs/ocfs2/buffer_head_io.h | 4 ++--
+ fs/ocfs2/dir.c | 2 +-
+ fs/ocfs2/inode.c | 3 ++-
+ fs/ocfs2/journal.c | 3 ++-
+ fs/ocfs2/localalloc.c | 4 ++--
+ fs/ocfs2/slot_map.c | 6 ++++--
+ 7 files changed, 24 insertions(+), 17 deletions(-)
+
+Index: linux-2.6.27/fs/ocfs2/buffer_head_io.c
+===================================================================
+--- linux-2.6.27.orig/fs/ocfs2/buffer_head_io.c
++++ linux-2.6.27/fs/ocfs2/buffer_head_io.c
+@@ -181,7 +181,8 @@ int ocfs2_read_blocks(struct inode *inod
+ inode, (unsigned long long)block, nr, flags);
+
+ BUG_ON(!inode);
+- BUG_ON((flags & OCFS2_BH_READAHEAD) && !(flags & OCFS2_BH_CACHED));
++ BUG_ON((flags & OCFS2_BH_READAHEAD) &&
++ (flags & OCFS2_BH_IGNORE_CACHE));
+
+ if (bhs == NULL) {
+ status = -EINVAL;
+@@ -214,7 +215,7 @@ int ocfs2_read_blocks(struct inode *inod
+ }
+ }
+ bh = bhs[i];
+- ignore_cache = 0;
++ ignore_cache = (flags & OCFS2_BH_IGNORE_CACHE);
+
+ /* There are three read-ahead cases here which we need to
+ * be concerned with. All three assume a buffer has
+@@ -240,26 +241,27 @@ int ocfs2_read_blocks(struct inode *inod
+ * before our is-it-in-flight check.
+ */
+
+- if (flags & OCFS2_BH_CACHED &&
+- !ocfs2_buffer_uptodate(inode, bh)) {
++ if (!ignore_cache && !ocfs2_buffer_uptodate(inode, bh)) {
+ mlog(ML_UPTODATE,
+ "bh (%llu), inode %llu not uptodate\n",
+ (unsigned long long)bh->b_blocknr,
+ (unsigned long long)OCFS2_I(inode)->ip_blkno);
++ /* We're using ignore_cache here to say
++ * "go to disk" */
+ ignore_cache = 1;
+ }
+
+ /* XXX: Can we ever get this and *not* have the cached
+ * flag set? */
+ if (buffer_jbd(bh)) {
+- if (!(flags & OCFS2_BH_CACHED) || ignore_cache)
++ if (ignore_cache)
+ mlog(ML_BH_IO, "trying to sync read a jbd "
+ "managed bh (blocknr = %llu)\n",
+ (unsigned long long)bh->b_blocknr);
+ continue;
+ }
+
+- if (!(flags & OCFS2_BH_CACHED) || ignore_cache) {
++ if (ignore_cache) {
+ if (buffer_dirty(bh)) {
+ /* This should probably be a BUG, or
+ * at least return an error. */
+@@ -294,7 +296,7 @@ int ocfs2_read_blocks(struct inode *inod
+ * previously read-ahead buffer may have
+ * completed I/O while we were waiting for the
+ * buffer lock. */
+- if ((flags & OCFS2_BH_CACHED)
++ if (!(flags & OCFS2_BH_IGNORE_CACHE)
+ && !(flags & OCFS2_BH_READAHEAD)
+ && ocfs2_buffer_uptodate(inode, bh)) {
+ unlock_buffer(bh);
+@@ -344,7 +346,8 @@ int ocfs2_read_blocks(struct inode *inod
+
+ mlog(ML_BH_IO, "block=(%llu), nr=(%d), cached=%s, flags=0x%x\n",
+ (unsigned long long)block, nr,
+- (!(flags & OCFS2_BH_CACHED) || ignore_cache) ? "no" : "yes", flags);
++ ((flags & OCFS2_BH_IGNORE_CACHE) || ignore_cache) ? "no" : "yes",
++ flags);
+
+ bail:
+
+Index: linux-2.6.27/fs/ocfs2/buffer_head_io.h
+===================================================================
+--- linux-2.6.27.orig/fs/ocfs2/buffer_head_io.h
++++ linux-2.6.27/fs/ocfs2/buffer_head_io.h
+@@ -49,7 +49,7 @@ int ocfs2_read_blocks_sync(struct ocfs2_
+ int ocfs2_write_super_or_backup(struct ocfs2_super *osb,
+ struct buffer_head *bh);
+
+-#define OCFS2_BH_CACHED 1
++#define OCFS2_BH_IGNORE_CACHE 1
+ #define OCFS2_BH_READAHEAD 8
+
+ static inline int ocfs2_read_block(struct inode *inode, u64 off,
+@@ -63,7 +63,7 @@ static inline int ocfs2_read_block(struc
+ goto bail;
+ }
+
+- status = ocfs2_read_blocks(inode, off, 1, bh, OCFS2_BH_CACHED);
++ status = ocfs2_read_blocks(inode, off, 1, bh, 0);
+
+ bail:
+ return status;
+Index: linux-2.6.27/fs/ocfs2/dir.c
+===================================================================
+--- linux-2.6.27.orig/fs/ocfs2/dir.c
++++ linux-2.6.27/fs/ocfs2/dir.c
+@@ -88,7 +88,7 @@ static struct buffer_head *ocfs2_bread(s
+ struct buffer_head *bh = NULL;
+ int tmperr;
+ u64 p_blkno;
+- int readflags = OCFS2_BH_CACHED;
++ int readflags = 0;
+
+ if (reada)
+ readflags |= OCFS2_BH_READAHEAD;
+Index: linux-2.6.27/fs/ocfs2/inode.c
+===================================================================
+--- linux-2.6.27.orig/fs/ocfs2/inode.c
++++ linux-2.6.27/fs/ocfs2/inode.c
+@@ -461,7 +461,8 @@ static int ocfs2_read_locked_inode(struc
+ }
+
+ if (can_lock)
+- status = ocfs2_read_blocks(inode, args->fi_blkno, 1, &bh, 0);
++ status = ocfs2_read_blocks(inode, args->fi_blkno, 1, &bh,
++ OCFS2_BH_IGNORE_CACHE);
+ else
+ status = ocfs2_read_blocks_sync(osb, args->fi_blkno, 1, &bh);
+ if (status < 0) {
+Index: linux-2.6.27/fs/ocfs2/journal.c
+===================================================================
+--- linux-2.6.27.orig/fs/ocfs2/journal.c
++++ linux-2.6.27/fs/ocfs2/journal.c
+@@ -1134,7 +1134,8 @@ static int ocfs2_read_journal_inode(stru
+ }
+ SET_INODE_JOURNAL(inode);
+
+- status = ocfs2_read_blocks(inode, OCFS2_I(inode)->ip_blkno, 1, bh, 0);
++ status = ocfs2_read_blocks(inode, OCFS2_I(inode)->ip_blkno, 1, bh,
++ OCFS2_BH_IGNORE_CACHE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+Index: linux-2.6.27/fs/ocfs2/localalloc.c
+===================================================================
+--- linux-2.6.27.orig/fs/ocfs2/localalloc.c
++++ linux-2.6.27/fs/ocfs2/localalloc.c
+@@ -249,7 +249,7 @@ int ocfs2_load_local_alloc(struct ocfs2_
+ }
+
+ status = ocfs2_read_blocks(inode, OCFS2_I(inode)->ip_blkno, 1,
+- &alloc_bh, 0);
++ &alloc_bh, OCFS2_BH_IGNORE_CACHE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+@@ -460,7 +460,7 @@ int ocfs2_begin_local_alloc_recovery(str
+ mutex_lock(&inode->i_mutex);
+
+ status = ocfs2_read_blocks(inode, OCFS2_I(inode)->ip_blkno, 1,
+- &alloc_bh, 0);
++ &alloc_bh, OCFS2_BH_IGNORE_CACHE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+Index: linux-2.6.27/fs/ocfs2/slot_map.c
+===================================================================
+--- linux-2.6.27.orig/fs/ocfs2/slot_map.c
++++ linux-2.6.27/fs/ocfs2/slot_map.c
+@@ -150,7 +150,8 @@ int ocfs2_refresh_slot_info(struct ocfs2
+ * be !NULL. Thus, ocfs2_read_blocks() will ignore blocknr. If
+ * this is not true, the read of -1 (UINT64_MAX) will fail.
+ */
+- ret = ocfs2_read_blocks(si->si_inode, -1, si->si_blocks, si->si_bh, 0);
++ ret = ocfs2_read_blocks(si->si_inode, -1, si->si_blocks, si->si_bh,
++ OCFS2_BH_IGNORE_CACHE);
+ if (ret == 0) {
+ spin_lock(&osb->osb_lock);
+ ocfs2_update_slot_info(si);
+@@ -403,7 +404,8 @@ static int ocfs2_map_slot_buffers(struct
+ (unsigned long long)blkno);
+
+ bh = NULL; /* Acquire a fresh bh */
+- status = ocfs2_read_blocks(si->si_inode, blkno, 1, &bh, 0);
++ status = ocfs2_read_blocks(si->si_inode, blkno, 1, &bh,
++ OCFS2_BH_IGNORE_CACHE);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
projects / people / pmueller / ipfire-2.x.git / blobdiff