linux/fs/fuse, branch v4.0

fuse: explicitly set /dev/fuse file's private_data

2015-03-19T14:29:22Z

The misc subsystem (which is used for /dev/fuse) initializes private_data to point to the misc device when a driver has registered a custom open file operation, and initializes it to NULL when a custom open file operation has *not* been provided. This subtle quirk is confusing, to the point where kernel code registers *empty* file open operations to have private_data point to the misc device structure. And it leads to bugs, where the addition or removal of a custom open file operation surprisingly changes the initial contents of a file's private_data structure. So to simplify things in the misc subsystem, a patch [1] has been proposed to *always* set the private_data to point to the misc device, instead of only doing this when a custom open file operation has been registered. But before this patch can be applied we need to modify drivers that make the assumption that a misc device file's private_data is initialized to NULL because they didn't register a custom open file operation, so they don't rely on this assumption anymore. FUSE uses private_data to store the fuse_conn and errors out if this is not initialized to NULL at mount time. Hence, we now set a file's private_data to NULL explicitly, to be independent of whatever value the misc subsystem initializes it to by default. [1] https://lkml.org/lkml/2014/12/4/939 Reported-by: Giedrius Statkevicius Reported-by: Thierry Reding Signed-off-by: Tom Van Braeckel Signed-off-by: Miklos Szeredi

fuse: set stolen page uptodate

2015-02-26T10:45:47Z

Regular pipe buffers' ->steal method (generic_pipe_buf_steal()) doesn't set PG_uptodate. Don't warn on this condition, just set the uptodate flag. Signed-off-by: Miklos Szeredi Cc: stable@vger.kernel.org

fuse: notify: don't move pages

2015-02-26T10:45:47Z

fuse_try_move_page() is not prepared for replacing pages that have already been read. Reported-by: Al Viro Signed-off-by: Miklos Szeredi Cc: stable@vger.kernel.org

VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)

2015-02-22T16:38:41Z

Convert the following where appropriate: (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry). (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry). (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more complicated than it appears as some calls should be converted to d_can_lookup() instead. The difference is whether the directory in question is a real dir with a ->lookup op or whether it's a fake dir with a ->d_automount op. In some circumstances, we can subsume checks for dentry->d_inode not being NULL into this, provided we the code isn't in a filesystem that expects d_inode to be NULL if the dirent really *is* negative (ie. if we're going to use d_inode() rather than d_backing_inode() to get the inode pointer). Note that the dentry type field may be set to something other than DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS manages the fall-through from a negative dentry to a lower layer. In such a case, the dentry type of the negative union dentry is set to the same as the type of the lower dentry. However, if you know d_inode is not NULL at the call site, then you can use the d_is_xxx() functions even in a filesystem. There is one further complication: a 0,0 chardev dentry may be labelled DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was intended for special directory entry types that don't have attached inodes. The following perl+coccinelle script was used: use strict; my @callers; open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') || die "Can't grep for S_ISDIR and co. callers"; @callers = <$fd>; close($fd); unless (@callers) { print "No matches\n"; exit(0); } my @cocci = ( '@@', 'expression E;', '@@', '', '- S_ISLNK(E->d_inode->i_mode)', '+ d_is_symlink(E)', '', '@@', 'expression E;', '@@', '', '- S_ISDIR(E->d_inode->i_mode)', '+ d_is_dir(E)', '', '@@', 'expression E;', '@@', '', '- S_ISREG(E->d_inode->i_mode)', '+ d_is_reg(E)' ); my $coccifile = "tmp.sp.cocci"; open($fd, ">$coccifile") || die $coccifile; print($fd "$_\n") || die $coccifile foreach (@cocci); close($fd); foreach my $file (@callers) { chomp $file; print "Processing ", $file, "\n"; system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 || die "spatch failed"; } [AV: overlayfs parts skipped] Signed-off-by: David Howells Signed-off-by: Al Viro

Merge branch 'for-3.20/bdi' of git://git.kernel.dk/linux-block

2015-02-12T21:50:21Z

Pull backing device changes from Jens Axboe: "This contains a cleanup of how the backing device is handled, in preparation for a rework of the life time rules. In this part, the most important change is to split the unrelated nommu mmap flags from it, but also removing a backing_dev_info pointer from the address_space (and inode), and a cleanup of other various minor bits. Christoph did all the work here, I just fixed an oops with pages that have a swap backing. Arnd fixed a missing export, and Oleg killed the lustre backing_dev_info from staging. Last patch was from Al, unexporting parts that are now no longer needed outside" * 'for-3.20/bdi' of git://git.kernel.dk/linux-block: Make super_blocks and sb_lock static mtd: export new mtd_mmap_capabilities fs: make inode_to_bdi() handle NULL inode staging/lustre/llite: get rid of backing_dev_info fs: remove default_backing_dev_info fs: don't reassign dirty inodes to default_backing_dev_info nfs: don't call bdi_unregister ceph: remove call to bdi_unregister fs: remove mapping->backing_dev_info fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info nilfs2: set up s_bdi like the generic mount_bdev code block_dev: get bdev inode bdi directly from the block device block_dev: only write bdev inode on close fs: introduce f_op->mmap_capabilities for nommu mmap support fs: kill BDI_CAP_SWAP_BACKED fs: deduplicate noop_backing_dev_info

mm: drop vm_ops->remap_pages and generic_file_remap_pages() stub

2015-02-10T22:30:30Z

Nobody uses it anymore. [akpm@linux-foundation.org: fix filemap_xip.c] Signed-off-by: Kirill A. Shutemov Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs: remove mapping->backing_dev_info

2015-01-20T21:03:05Z

Now that we never use the backing_dev_info pointer in struct address_space we can simply remove it and save 4 to 8 bytes in every inode. Signed-off-by: Christoph Hellwig Acked-by: Ryusuke Konishi Reviewed-by: Tejun Heo Reviewed-by: Jan Kara Signed-off-by: Jens Axboe

fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info

2015-01-20T21:03:04Z

Now that we got rid of the bdi abuse on character devices we can always use sb->s_bdi to get at the backing_dev_info for a file, except for the block device special case. Export inode_to_bdi and replace uses of mapping->backing_dev_info with it to prepare for the removal of mapping->backing_dev_info. Signed-off-by: Christoph Hellwig Reviewed-by: Tejun Heo Reviewed-by: Jan Kara Signed-off-by: Jens Axboe

fuse: add memory barrier to INIT

2015-01-06T09:45:35Z

Theoretically we need to order setting of various fields in fc with fc->initialized. No known bug reports related to this yet. Signed-off-by: Miklos Szeredi

fuse: fix LOOKUP vs INIT compat handling

2015-01-06T09:45:35Z

Analysis from Marc: "Commit 7078187a795f ("fuse: introduce fuse_simple_request() helper") from the above pull request triggers some EIO errors for me in some tests that rely on fuse Looking at the code changes and a bit of debugging info I think there's a general problem here that fuse_get_req checks and possibly waits for fc->initialized, and this was always called first. But this commit changes the ordering and in many places fc->minor is now possibly used before fuse_get_req, and we can't be sure that fc has been initialized. In my case fuse_lookup_init sets req->out.args[0].size to the wrong size because fc->minor at that point is still 0, leading to the EIO error." Fix by moving the compat adjustments into fuse_simple_request() to after fuse_get_req(). This is also more readable than the original, since now compatibility is handled in a single function instead of cluttering each operation. Reported-by: Marc Dionne Tested-by: Marc Dionne Signed-off-by: Miklos Szeredi Fixes: 7078187a795f ("fuse: introduce fuse_simple_request() helper")