diff options
Diffstat (limited to 'fs/ocfs2/buffer_head_io.c')
-rw-r--r-- | fs/ocfs2/buffer_head_io.c | 134 |
1 files changed, 104 insertions, 30 deletions
diff --git a/fs/ocfs2/buffer_head_io.c b/fs/ocfs2/buffer_head_io.c index f136639..7e947c6 100644 --- a/fs/ocfs2/buffer_head_io.c +++ b/fs/ocfs2/buffer_head_io.c @@ -66,7 +66,7 @@ int ocfs2_write_block(struct ocfs2_super *osb, struct buffer_head *bh, /* remove from dirty list before I/O. */ clear_buffer_dirty(bh); - get_bh(bh); /* for end_buffer_write_sync() */ + get_bh(bh); /* for end_buffer_write_sync() */ bh->b_end_io = end_buffer_write_sync; submit_bh(WRITE, bh); @@ -88,22 +88,103 @@ out: return ret; } -int ocfs2_read_blocks(struct ocfs2_super *osb, u64 block, int nr, - struct buffer_head *bhs[], int flags, - struct inode *inode) +int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block, + unsigned int nr, struct buffer_head *bhs[]) +{ + int status = 0; + unsigned int i; + struct buffer_head *bh; + + if (!nr) { + mlog(ML_BH_IO, "No buffers will be read!\n"); + goto bail; + } + + for (i = 0 ; i < nr ; i++) { + if (bhs[i] == NULL) { + bhs[i] = sb_getblk(osb->sb, block++); + if (bhs[i] == NULL) { + status = -EIO; + mlog_errno(status); + goto bail; + } + } + bh = bhs[i]; + + if (buffer_jbd(bh)) { + mlog(ML_ERROR, + "trying to sync read a jbd " + "managed bh (blocknr = %llu), skipping\n", + (unsigned long long)bh->b_blocknr); + continue; + } + + if (buffer_dirty(bh)) { + /* This should probably be a BUG, or + * at least return an error. */ + mlog(ML_ERROR, + "trying to sync read a dirty " + "buffer! (blocknr = %llu), skipping\n", + (unsigned long long)bh->b_blocknr); + continue; + } + + lock_buffer(bh); + if (buffer_jbd(bh)) { + mlog(ML_ERROR, + "block %llu had the JBD bit set " + "while I was in lock_buffer!", + (unsigned long long)bh->b_blocknr); + BUG(); + } + + clear_buffer_uptodate(bh); + get_bh(bh); /* for end_buffer_read_sync() */ + bh->b_end_io = end_buffer_read_sync; + submit_bh(READ, bh); + } + + for (i = nr; i > 0; i--) { + bh = bhs[i - 1]; + + if (buffer_jbd(bh)) { + mlog(ML_ERROR, + "the journal got the buffer while it was " + "locked for io! (blocknr = %llu)\n", + (unsigned long long)bh->b_blocknr); + BUG(); + } + + wait_on_buffer(bh); + if (!buffer_uptodate(bh)) { + /* Status won't be cleared from here on out, + * so we can safely record this and loop back + * to cleanup the other buffers. */ + status = -EIO; + put_bh(bh); + bhs[i - 1] = NULL; + } + } + +bail: + return status; +} + +int ocfs2_read_blocks(struct inode *inode, u64 block, int nr, + struct buffer_head *bhs[], int flags) { int status = 0; - struct super_block *sb; int i, ignore_cache = 0; struct buffer_head *bh; - mlog_entry("(block=(%llu), nr=(%d), flags=%d, inode=%p)\n", - (unsigned long long)block, nr, flags, inode); + mlog_entry("(inode=%p, block=(%llu), nr=(%d), flags=%d)\n", + inode, (unsigned long long)block, nr, flags); + BUG_ON(!inode); BUG_ON((flags & OCFS2_BH_READAHEAD) && - (!inode || !(flags & OCFS2_BH_CACHED))); + (flags & OCFS2_BH_IGNORE_CACHE)); - if (osb == NULL || osb->sb == NULL || bhs == NULL) { + if (bhs == NULL) { status = -EINVAL; mlog_errno(status); goto bail; @@ -122,26 +203,19 @@ int ocfs2_read_blocks(struct ocfs2_super *osb, u64 block, int nr, goto bail; } - sb = osb->sb; - - if (flags & OCFS2_BH_CACHED && !inode) - flags &= ~OCFS2_BH_CACHED; - - if (inode) - mutex_lock(&OCFS2_I(inode)->ip_io_mutex); + mutex_lock(&OCFS2_I(inode)->ip_io_mutex); for (i = 0 ; i < nr ; i++) { if (bhs[i] == NULL) { - bhs[i] = sb_getblk(sb, block++); + bhs[i] = sb_getblk(inode->i_sb, block++); if (bhs[i] == NULL) { - if (inode) - mutex_unlock(&OCFS2_I(inode)->ip_io_mutex); + mutex_unlock(&OCFS2_I(inode)->ip_io_mutex); status = -EIO; mlog_errno(status); goto bail; } } 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 @@ -167,26 +241,27 @@ int ocfs2_read_blocks(struct ocfs2_super *osb, u64 block, int nr, * 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. */ @@ -221,7 +296,7 @@ int ocfs2_read_blocks(struct ocfs2_super *osb, u64 block, int nr, * 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); @@ -265,15 +340,14 @@ int ocfs2_read_blocks(struct ocfs2_super *osb, u64 block, int nr, /* Always set the buffer in the cache, even if it was * a forced read, or read-ahead which hasn't yet * completed. */ - if (inode) - ocfs2_set_buffer_uptodate(inode, bh); + ocfs2_set_buffer_uptodate(inode, bh); } - if (inode) - mutex_unlock(&OCFS2_I(inode)->ip_io_mutex); + mutex_unlock(&OCFS2_I(inode)->ip_io_mutex); 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: |