diff options
Diffstat (limited to 'fs/ext2/fsync.c')
| -rw-r--r-- | fs/ext2/fsync.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/fs/ext2/fsync.c b/fs/ext2/fsync.c new file mode 100644 index 000000000..2f79c4749 --- /dev/null +++ b/fs/ext2/fsync.c @@ -0,0 +1,198 @@ +/* + * linux/fs/ext2/fsync.c + * + * Copyright (C) 1993 Stephen Tweedie (sct@dcs.ed.ac.uk) + * from + * Copyright (C) 1992 Remy Card (card@masi.ibp.fr) + * Laboratoire MASI - Institut Blaise Pascal + * Universite Pierre et Marie Curie (Paris VI) + * from + * linux/fs/minix/truncate.c Copyright (C) 1991, 1992 Linus Torvalds + * + * ext2fs fsync primitive + */ + +#include <asm/segment.h> +#include <asm/system.h> + +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/ext2_fs.h> +#include <linux/fcntl.h> +#include <linux/sched.h> +#include <linux/stat.h> +#include <linux/locks.h> + + +#define blocksize (EXT2_BLOCK_SIZE(inode->i_sb)) +#define addr_per_block (EXT2_ADDR_PER_BLOCK(inode->i_sb)) + +static int sync_block (struct inode * inode, unsigned long * block, int wait) +{ + struct buffer_head * bh; + int tmp; + + if (!*block) + return 0; + tmp = *block; + bh = get_hash_table (inode->i_dev, *block, blocksize); + if (!bh) + return 0; + if (*block != tmp) { + brelse (bh); + return 1; + } + if (wait && bh->b_req && !bh->b_uptodate) { + brelse (bh); + return -1; + } + if (wait || !bh->b_uptodate || !bh->b_dirt) { + brelse (bh); + return 0; + } + ll_rw_block (WRITE, 1, &bh); + bh->b_count--; + return 0; +} + +static int sync_iblock (struct inode * inode, unsigned long * iblock, + struct buffer_head ** bh, int wait) +{ + int rc, tmp; + + *bh = NULL; + tmp = *iblock; + if (!tmp) + return 0; + rc = sync_block (inode, iblock, wait); + if (rc) + return rc; + *bh = bread (inode->i_dev, tmp, blocksize); + if (tmp != *iblock) { + brelse (*bh); + *bh = NULL; + return 1; + } + if (!*bh) + return -1; + return 0; +} + + +static int sync_direct (struct inode * inode, int wait) +{ + int i; + int rc, err = 0; + + for (i = 0; i < EXT2_NDIR_BLOCKS; i++) { + rc = sync_block (inode, inode->u.ext2_i.i_data + i, wait); + if (rc > 0) + break; + if (rc) + err = rc; + } + return err; +} + +static int sync_indirect (struct inode * inode, unsigned long * iblock, + int wait) +{ + int i; + struct buffer_head * ind_bh; + int rc, err = 0; + + rc = sync_iblock (inode, iblock, &ind_bh, wait); + if (rc || !ind_bh) + return rc; + + for (i = 0; i < addr_per_block; i++) { + rc = sync_block (inode, + ((unsigned long *) ind_bh->b_data) + i, + wait); + if (rc > 0) + break; + if (rc) + err = rc; + } + brelse (ind_bh); + return err; +} + +static int sync_dindirect (struct inode * inode, unsigned long * diblock, + int wait) +{ + int i; + struct buffer_head * dind_bh; + int rc, err = 0; + + rc = sync_iblock (inode, diblock, &dind_bh, wait); + if (rc || !dind_bh) + return rc; + + for (i = 0; i < addr_per_block; i++) { + rc = sync_indirect (inode, + ((unsigned long *) dind_bh->b_data) + i, + wait); + if (rc > 0) + break; + if (rc) + err = rc; + } + brelse (dind_bh); + return err; +} + +static int sync_tindirect (struct inode * inode, unsigned long * tiblock, + int wait) +{ + int i; + struct buffer_head * tind_bh; + int rc, err = 0; + + rc = sync_iblock (inode, tiblock, &tind_bh, wait); + if (rc || !tind_bh) + return rc; + + for (i = 0; i < addr_per_block; i++) { + rc = sync_dindirect (inode, + ((unsigned long *) tind_bh->b_data) + i, + wait); + if (rc > 0) + break; + if (rc) + err = rc; + } + brelse (tind_bh); + return err; +} + +int ext2_sync_file (struct inode * inode, struct file * file) +{ + int wait, err = 0; + + if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || + S_ISLNK(inode->i_mode))) + return -EINVAL; + if (S_ISLNK(inode->i_mode) && !(inode->i_blocks)) + /* + * Don't sync fast links! + */ + goto skip; + + for (wait=0; wait<=1; wait++) + { + err |= sync_direct (inode, wait); + err |= sync_indirect (inode, + inode->u.ext2_i.i_data+EXT2_IND_BLOCK, + wait); + err |= sync_dindirect (inode, + inode->u.ext2_i.i_data+EXT2_DIND_BLOCK, + wait); + err |= sync_tindirect (inode, + inode->u.ext2_i.i_data+EXT2_TIND_BLOCK, + wait); + } +skip: + err |= ext2_sync_inode (inode); + return (err < 0) ? -EIO : 0; +} |