Snapshots of nilfs are read-only.
After super block instances (sb) will be unified, nilfs will need to
check write access by a way other than implicit test with
IS_RDONLY(inode). This is because IS_RDONLY() refers to MS_RDONLY bit
of inode->i_sb->s_flags and it will become inaccurate after the
unification of sb.
To prepare for the issue, this uses i_op->permission to deny write
access to inodes in snapshots.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The previous export operations cannot handle multiple versions of
a filesystem if they belong to the same sb instance.
This adds a new type of file handle and extends export operations so
that they can get the inode specified by a checkpoint number as well
as an inode number and a generation number.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This puts a pointer to nilfs_root object in the private part of
on-memory inode, and makes nilfs_iget function pick up the inode with
the same root object.
Non-root inodes inherit its nilfs_root object from parent inode. That
of the root inode is allocated through nilfs_attach_checkpoint()
function.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Replace mark_inode_dirty() as nilfs_mark_inode_dirty()
to reduce deep function calls.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Delete mark_inode_dirty() in nilfs_delete_entry() to reduce duplicate
mark_inode_dirty() calls both in nilfs_rename() and nilfs_delete_entry().
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Delete mark_inode_dirty() in nilfs_commit_chunk(), for callers of
nilfs_commit_chunk() will call equivalent mark_inode_dirty()
after calling nilfs_commit_chunk().
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Split nilfs_unlink() to reduce nested transaction and duplicate
mark_inode_dirty() calls when calling nilfs_unlink() from nilfs_rmdir().
nilfs_do_unlink() is an actual unlink functionality which is not
in transaction and does not call mark_inode_dirty() for dentry argument.
nilfs_unlink() is a wrapper function for do_nilfs_unlink() with
transaction and mark_inode_dirty() for dentry argument.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This is an intermidiate patch to reduce redandunt mark_inode_dirty() calls
by calling inode_inc_link_count() and inode_dec_link_count() functions.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
It is redundant to call mark_inode_dirty() in nilfs_new_inode() because
all caller of nilfs_new_inode() will call mark_inode_dirty()
after calling nilfs_new_inode() directly or indirectly in transaction.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Pekka Enberg pointed out that double error handlings found after
nilfs_transaction_end() can be avoided by separating abort operation:
OK, I don't understand this. The only way nilfs_transaction_end() can
fail is if we have NILFS_TI_SYNC set and we fail to construct the
segment. But why do we want to construct a segment if we don't commit?
I guess what I'm asking is why don't we have a separate
nilfs_transaction_abort() function that can't fail for the erroneous
case to avoid this double error value tracking thing?
This does the separation and renames nilfs_transaction_end() to
nilfs_transaction_commit() for clarification.
Since, some calls of these functions were used just for exclusion control
against the segment constructor, they are replaced with semaphore
operations.
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds pathname operations, most of which comes from the ext2 file
system.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>