[PATCH v2] REQ_META set during meta data write
From: Saugata Das <hidden>
Date: 2012-03-02 12:45:09
Also in:
linux-fsdevel
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
From: Saugata Das <redacted> Today, storage devices like eMMC has special features like data tagging (introduced in MMC-4.5 version) in order to improve performance of some specific writes. On MMC stack, data tagging is used for all writes which has REQ_META flag set. On EXT4, however, currently REQ_META is set only for read. This patch adds the capability to add REQ_META flag during meta data write. This patch adds new function set_buffer_meta, which is used to set a bit BH_Meta in the b_state field when meta data and super block is made dirty. Signed-off-by: Saugata Das <redacted> Acked-by: Arnd Bergmann <redacted> Changelog v2: - Removed check for WRITE when setting REQ_META in submit_bh Changelog v1: - Introduction of REQ_META during write --- fs/buffer.c | 3 +++ fs/ext4/ext4_jbd2.c | 4 ++++ fs/ext4/inode.c | 4 +++- include/linux/buffer_head.h | 2 ++ 4 files changed, 12 insertions(+), 1 deletions(-)
diff --git a/fs/buffer.c b/fs/buffer.c
index 19d8eb7..6eaf492 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c@@ -2926,6 +2926,9 @@ int submit_bh(int rw, struct buffer_head * bh) if (test_set_buffer_req(bh) && (rw & WRITE)) clear_buffer_write_io_error(bh); + if (buffer_meta(bh)) + rw |= REQ_META; + /* * from here on down, it's all bio -- do the initial mapping, * submit_bio -> generic_make_request may further map this bio around
diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index aca1790..097c062 100644
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c@@ -107,6 +107,8 @@ int __ext4_handle_dirty_metadata(const char *where, unsigned int line, { int err = 0; + set_buffer_meta(bh); + if (ext4_handle_valid(handle)) { err = jbd2_journal_dirty_metadata(handle, bh); if (err) {
@@ -143,6 +145,8 @@ int __ext4_handle_dirty_super(const char *where, unsigned int line, struct buffer_head *bh = EXT4_SB(sb)->s_sbh; int err = 0; + set_buffer_meta(bh); + if (ext4_handle_valid(handle)) { err = jbd2_journal_dirty_metadata(handle, bh); if (err)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 92655fd..105e1d0 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c@@ -4144,8 +4144,10 @@ int ext4_write_inode(struct inode *inode, struct writeback_control *wbc) err = __ext4_get_inode_loc(inode, &iloc, 0); if (err) return err; - if (wbc->sync_mode == WB_SYNC_ALL) + if (wbc->sync_mode == WB_SYNC_ALL) { + set_buffer_meta(iloc.bh); sync_dirty_buffer(iloc.bh); + } if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) { EXT4_ERROR_INODE_BLOCK(inode, iloc.bh->b_blocknr, "IO error syncing inode");
diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index 458f497..13bba17 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h@@ -34,6 +34,7 @@ enum bh_state_bits { BH_Write_EIO, /* I/O error on write */ BH_Unwritten, /* Buffer is allocated on disk but not written */ BH_Quiet, /* Buffer Error Prinks to be quiet */ + BH_Meta, /* Is meta */ BH_PrivateStart,/* not a state bit, but the first bit available * for private allocation by other entities
@@ -124,6 +125,7 @@ BUFFER_FNS(Delay, delay) BUFFER_FNS(Boundary, boundary) BUFFER_FNS(Write_EIO, write_io_error) BUFFER_FNS(Unwritten, unwritten) +BUFFER_FNS(Meta, meta) #define bh_offset(bh) ((unsigned long)(bh)->b_data & ~PAGE_MASK) #define touch_buffer(bh) mark_page_accessed(bh->b_page)
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1.7.4.3