[PATCH v2 2/7] xfs: simplify xfs_buf_get / xfs_buf_read interfaces

Christoph Hellwig
2009-11-24T18:01:57Z

Currently these lowlevel buffer cache interfaces are highly confusing
as we have a _flags variant of each that does actually respect the flags,
and one without _flags which has a flags argument that gets ignored and
overriden with a default set. Given that very few places use the default
arguments get rid of the duplication and convert all callers to pass the
flags explicitly. Also remove the now confusing _flags postfix.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: xfs/fs/xfs/linux-2.6/xfs_buf.h
===================================================================
--- xfs.orig/fs/xfs/linux-2.6/xfs_buf.h 2009-11-20 14:45:10.771004296 +0100
+++ xfs/fs/xfs/linux-2.6/xfs_buf.h 2009-11-20 14:51:49.614256096 +0100
@@ -187,15 +187,10 @@ extern xfs_buf_t *_xfs_buf_find(xfs_buft
#define xfs_incore(buftarg,blkno,len,lockit) \
_xfs_buf_find(buftarg, blkno ,len, lockit, NULL)

-extern xfs_buf_t *xfs_buf_get_flags(xfs_buftarg_t *, xfs_off_t, size_t,
+extern xfs_buf_t *xfs_buf_get(xfs_buftarg_t *, xfs_off_t, size_t,
xfs_buf_flags_t);
-#define xfs_buf_get(target, blkno, len, flags) \
- xfs_buf_get_flags((target), (blkno), (len), XBF_LOCK | XBF_MAPPED)
-
-extern xfs_buf_t *xfs_buf_read_flags(xfs_buftarg_t *, xfs_off_t, size_t,
+extern xfs_buf_t *xfs_buf_read(xfs_buftarg_t *, xfs_off_t, size_t,
xfs_buf_flags_t);
-#define xfs_buf_read(target, blkno, len, flags) \
- xfs_buf_read_flags((target), (blkno), (len), XBF_LOCK | XBF_MAPPED)

extern xfs_buf_t *xfs_buf_get_empty(size_t, xfs_buftarg_t *);
extern xfs_buf_t *xfs_buf_get_noaddr(size_t, xfs_buftarg_t *);
Index: xfs/fs/xfs/xfs_log_recover.c
===================================================================
--- xfs.orig/fs/xfs/xfs_log_recover.c 2009-11-20 14:45:10.776004095 +0100
+++ xfs/fs/xfs/xfs_log_recover.c 2009-11-20 14:48:01.412255985 +0100
@@ -2206,6 +2206,7 @@ xlog_recover_do_buffer_trans(
xfs_daddr_t blkno;
int len;
ushort flags;
+ uint buf_flags;

buf_f = (xfs_buf_log_format_t *)item->ri_buf[0].i_addr;

@@ -2246,12 +2247,11 @@ xlog_recover_do_buffer_trans(
}

mp = log->l_mp;
- if (flags & XFS_BLI_INODE_BUF) {
- bp = xfs_buf_read_flags(mp->m_ddev_targp, blkno, len,
- XFS_BUF_LOCK);
- } else {
- bp = xfs_buf_read(mp->m_ddev_targp, blkno, len, 0);
- }
+ buf_flags = XFS_BUF_LOCK;
+ if (!(flags & XFS_BLI_INODE_BUF))
+ buf_flags |= XFS_BUF_MAPPED;
+
+ bp = xfs_buf_read(mp->m_ddev_targp, blkno, len, buf_flags);
if (XFS_BUF_ISERROR(bp)) {
xfs_ioerror_alert("xlog_recover_do..(read#1)", log->l_mp,
bp, blkno);
@@ -2350,8 +2350,8 @@ xlog_recover_do_inode_trans(
goto error;
}

- bp = xfs_buf_read_flags(mp->m_ddev_targp, in_f->ilf_blkno,
- in_f->ilf_len, XFS_BUF_LOCK);
+ bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len,
+ XFS_BUF_LOCK);
if (XFS_BUF_ISERROR(bp)) {
xfs_ioerror_alert("xlog_recover_do..(read#2)", mp,
bp, in_f->ilf_blkno);
Index: xfs/fs/xfs/xfs_rw.c
===================================================================
--- xfs.orig/fs/xfs/xfs_rw.c 2009-11-20 14:45:10.781022821 +0100
+++ xfs/fs/xfs/xfs_rw.c 2009-11-20 14:47:08.756036097 +0100
@@ -277,10 +277,10 @@ xfs_read_buf(
xfs_buf_t *bp;
int error;

- if (flags)
- bp = xfs_buf_read_flags(target, blkno, len, flags);
- else
- bp = xfs_buf_read(target, blkno, len, flags);
+ if (!flags)
+ flags = XBF_LOCK | XBF_MAPPED;
+
+ bp = xfs_buf_read(target, blkno, len, flags);
if (!bp)
return XFS_ERROR(EIO);
error = XFS_BUF_GETERROR(bp);
Index: xfs/fs/xfs/xfs_fsops.c
===================================================================
--- xfs.orig/fs/xfs/xfs_fsops.c 2009-11-20 14:45:10.788004088 +0100
+++ xfs/fs/xfs/xfs_fsops.c 2009-11-20 14:50:40.324033258 +0100
@@ -201,8 +201,8 @@ xfs_growfs_data_private(
* AG freelist header block
*/
bp = xfs_buf_get(mp->m_ddev_targp,
- XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
- XFS_FSS_TO_BB(mp, 1), 0);
+ XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
+ XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
agf = XFS_BUF_TO_AGF(bp);
memset(agf, 0, mp->m_sb.sb_sectsize);
agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
@@ -233,8 +233,8 @@ xfs_growfs_data_private(
* AG inode header block
*/
bp = xfs_buf_get(mp->m_ddev_targp,
- XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
- XFS_FSS_TO_BB(mp, 1), 0);
+ XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
+ XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
agi = XFS_BUF_TO_AGI(bp);
memset(agi, 0, mp->m_sb.sb_sectsize);
agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
@@ -257,8 +257,9 @@ xfs_growfs_data_private(
* BNO btree root block
*/
bp = xfs_buf_get(mp->m_ddev_targp,
- XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
- BTOBB(mp->m_sb.sb_blocksize), 0);
+ XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
+ BTOBB(mp->m_sb.sb_blocksize),
+ XBF_LOCK | XBF_MAPPED);
block = XFS_BUF_TO_BLOCK(bp);
memset(block, 0, mp->m_sb.sb_blocksize);
block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
@@ -278,8 +279,9 @@ xfs_growfs_data_private(
* CNT btree root block
*/
bp = xfs_buf_get(mp->m_ddev_targp,
- XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
- BTOBB(mp->m_sb.sb_blocksize), 0);
+ XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
+ BTOBB(mp->m_sb.sb_blocksize),
+ XBF_LOCK | XBF_MAPPED);
block = XFS_BUF_TO_BLOCK(bp);
memset(block, 0, mp->m_sb.sb_blocksize);
block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
@@ -300,8 +302,9 @@ xfs_growfs_data_private(
* INO btree root block
*/
bp = xfs_buf_get(mp->m_ddev_targp,
- XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
- BTOBB(mp->m_sb.sb_blocksize), 0);
+ XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
+ BTOBB(mp->m_sb.sb_blocksize),
+ XBF_LOCK | XBF_MAPPED);
block = XFS_BUF_TO_BLOCK(bp);
memset(block, 0, mp->m_sb.sb_blocksize);
block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
Index: xfs/fs/xfs/linux-2.6/xfs_buf.c
===================================================================
--- xfs.orig/fs/xfs/linux-2.6/xfs_buf.c 2009-11-20 14:48:08.972276171 +0100
+++ xfs/fs/xfs/linux-2.6/xfs_buf.c 2009-11-20 14:51:31.077256872 +0100
@@ -582,7 +582,7 @@ found:
* although backing storage may not be.
*/
xfs_buf_t *
-xfs_buf_get_flags(
+xfs_buf_get(
xfs_buftarg_t *target,/* target for buffer */
xfs_off_t ioff, /* starting offset of range */
size_t isize, /* length of range */
@@ -661,7 +661,7 @@ _xfs_buf_read(
}

xfs_buf_t *
-xfs_buf_read_flags(
+xfs_buf_read(
xfs_buftarg_t *target,
xfs_off_t ioff,
size_t isize,
@@ -671,7 +671,7 @@ xfs_buf_read_flags(

flags |= XBF_READ;

- bp = xfs_buf_get_flags(target, ioff, isize, flags);
+ bp = xfs_buf_get(target, ioff, isize, flags);
if (bp) {
if (!XFS_BUF_ISDONE(bp)) {
XB_TRACE(bp, "read", (unsigned long)flags);
@@ -718,7 +718,7 @@ xfs_buf_readahead(
return;

flags |= (XBF_TRYLOCK|XBF_ASYNC|XBF_READ_AHEAD);
- xfs_buf_read_flags(target, ioff, isize, flags);
+ xfs_buf_read(target, ioff, isize, flags);
}

xfs_buf_t *
Index: xfs/fs/xfs/xfs_attr.c
===================================================================
--- xfs.orig/fs/xfs/xfs_attr.c 2009-11-20 14:49:18.048254421 +0100
+++ xfs/fs/xfs/xfs_attr.c 2009-11-20 14:51:13.539256422 +0100
@@ -2143,8 +2143,8 @@ xfs_attr_rmtval_set(xfs_da_args_t *args)
dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock),
blkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);

- bp = xfs_buf_get_flags(mp->m_ddev_targp, dblkno, blkcnt,
- XFS_BUF_LOCK | XBF_DONT_BLOCK);
+ bp = xfs_buf_get(mp->m_ddev_targp, dblkno, blkcnt,
+ XFS_BUF_LOCK | XBF_DONT_BLOCK);
ASSERT(bp);
ASSERT(!XFS_BUF_GETERROR(bp));

Index: xfs/fs/xfs/xfs_mount.c
===================================================================
--- xfs.orig/fs/xfs/xfs_mount.c 2009-11-20 14:45:56.032003740 +0100
+++ xfs/fs/xfs/xfs_mount.c 2009-11-20 14:47:03.268005820 +0100
@@ -583,8 +583,8 @@ xfs_readsb(xfs_mount_t *mp, int flags)
sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
extra_flags = XFS_BUF_LOCK | XFS_BUF_MANAGE | XFS_BUF_MAPPED;

- bp = xfs_buf_read_flags(mp->m_ddev_targp, XFS_SB_DADDR,
- BTOBB(sector_size), extra_flags);
+ bp = xfs_buf_read(mp->m_ddev_targp, XFS_SB_DADDR, BTOBB(sector_size),
+ extra_flags);
if (!bp || XFS_BUF_ISERROR(bp)) {
xfs_fs_mount_cmn_err(flags, "SB read failed");
error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
@@ -624,8 +624,8 @@ xfs_readsb(xfs_mount_t *mp, int flags)
XFS_BUF_UNMANAGE(bp);
xfs_buf_relse(bp);
sector_size = mp->m_sb.sb_sectsize;
- bp = xfs_buf_read_flags(mp->m_ddev_targp, XFS_SB_DADDR,
- BTOBB(sector_size), extra_flags);
+ bp = xfs_buf_read(mp->m_ddev_targp, XFS_SB_DADDR,
+ BTOBB(sector_size), extra_flags);
if (!bp || XFS_BUF_ISERROR(bp)) {
xfs_fs_mount_cmn_err(flags, "SB re-read failed");
error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
Index: xfs/fs/xfs/xfs_trans_buf.c
===================================================================
--- xfs.orig/fs/xfs/xfs_trans_buf.c 2009-11-20 14:45:56.049003881 +0100
+++ xfs/fs/xfs/xfs_trans_buf.c 2009-11-20 14:51:59.741006218 +0100
@@ -79,11 +79,8 @@ xfs_trans_get_buf(xfs_trans_t *tp,
/*
* Default to a normal get_buf() call if the tp is NULL.
*/
- if (tp == NULL) {
- bp = xfs_buf_get_flags(target_dev, blkno, len,
- flags | BUF_BUSY);
- return(bp);
- }
+ if (tp == NULL)
+ return xfs_buf_get(target_dev, blkno, len, flags | BUF_BUSY);

/*
* If we find the buffer in the cache with this transaction
@@ -129,7 +126,7 @@ xfs_trans_get_buf(xfs_trans_t *tp,
* easily deadlock with our current transaction as well as cause
* us to run out of stack space.
*/
- bp = xfs_buf_get_flags(target_dev, blkno, len, flags | BUF_BUSY);
+ bp = xfs_buf_get(target_dev, blkno, len, flags | BUF_BUSY);
if (bp == NULL) {
return NULL;
}
@@ -302,7 +299,7 @@ xfs_trans_read_buf(
* Default to a normal get_buf() call if the tp is NULL.
*/
if (tp == NULL) {
- bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY);
+ bp = xfs_buf_read(target, blkno, len, flags | BUF_BUSY);
if (!bp)
return (flags & XFS_BUF_TRYLOCK) ?
EAGAIN : XFS_ERROR(ENOMEM);
@@ -398,7 +395,7 @@ xfs_trans_read_buf(
* easily deadlock with our current transaction as well as cause
* us to run out of stack space.
*/
- bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY);
+ bp = xfs_buf_read(target, blkno, len, flags | BUF_BUSY);
if (bp == NULL) {
*bpp = NULL;
return 0;
Index: xfs/fs/xfs/xfs_vnodeops.c
===================================================================
--- xfs.orig/fs/xfs/xfs_vnodeops.c 2009-11-20 14:45:56.058003701 +0100
+++ xfs/fs/xfs/xfs_vnodeops.c 2009-11-20 14:47:59.262256187 +0100
@@ -538,9 +538,8 @@ xfs_readlink_bmap(
d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);

- bp = xfs_buf_read_flags(mp->m_ddev_targp, d, BTOBB(byte_cnt),
- XBF_LOCK | XBF_MAPPED |
- XBF_DONT_BLOCK);
+ bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt),
+ XBF_LOCK | XBF_MAPPED | XBF_DONT_BLOCK);
error = XFS_BUF_GETERROR(bp);
if (error) {
xfs_ioerror_alert("xfs_readlink",