kernel.git/fs/gfs2/dir.c, branch linux-3.18.y

gfs2: remove IS_ERR_VALUE abuse

2017-05-08T05:44:12Z

Picked from commit 287980e49ffc0f6d911601e7e352a812ed27768e ("remove lots of IS_ERR_VALUE abuses") upstream. The original fix that was backported to 3.18 already addressed the warning in some configurations, but not in others, leaving us with the same output: ../fs/gfs2/dir.c: In function 'get_first_leaf': ../fs/gfs2/dir.c:768:9: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized] error = get_leaf(dip, leaf_no, bh_out); ^ ../fs/gfs2/dir.c: In function 'dir_split_leaf.isra.20': ../fs/gfs2/dir.c:987:8: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized] This takes the approach that we took in later versions in mainline, but does not backport the entire patch, as that would be too large for stable and IIRC caused regressions in other drivers. Fixes: 9d46d31e9aea ("gfs2: avoid uninitialized variable warning") Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman

gfs2: avoid uninitialized variable warning

2017-04-30T03:49:16Z

commit 67893f12e5374bbcaaffbc6e570acbc2714ea884 upstream. We get a bogus warning about a potential uninitialized variable use in gfs2, because the compiler does not figure out that we never use the leaf number if get_leaf_nr() returns an error: fs/gfs2/dir.c: In function 'get_first_leaf': fs/gfs2/dir.c:802:9: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized] fs/gfs2/dir.c: In function 'dir_split_leaf': fs/gfs2/dir.c:1021:8: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized] Changing the 'if (!error)' to 'if (!IS_ERR_VALUE(error))' is sufficient to let gcc understand that this is exactly the same condition as in IS_ERR() so it can optimize the code path enough to understand it. Signed-off-by: Arnd Bergmann Signed-off-by: Bob Peterson Signed-off-by: Greg Kroah-Hartman

GFS2: Make rename not save dirent location

2014-10-01T13:06:15Z

This patch fixes a regression in the patch "GFS2: Remember directory insert point", commit 2b47dad866d04f14c328f888ba5406057b8c7d33. The problem had to do with the rename function: The function found space for the new dirent, and remembered that location. But then the old dirent was removed, which often moved the eligible location for the renamed dirent. Putting the new dirent at the saved location caused file system corruption. This patch adds a new "save_loc" variable to struct gfs2_diradd. If 1, the dirent location is saved. If 0, the dirent location is not saved and the buffer_head is released as per previous behavior. Signed-off-by: Bob Peterson Signed-off-by: Steven Whitehouse

GFS2: Use pr_ more consistently

2014-03-07T09:30:51Z

Add pr_fmt, remove embedded "GFS2: " prefixes. This now consistently emits lower case "gfs2: " for each message. Other miscellanea around these changes: o Add missing newlines o Coalesce formats o Realign arguments Signed-off-by: Joe Perches Signed-off-by: Steven Whitehouse

GFS2: global conversion to pr_foo()

2014-03-06T17:34:06Z

-All printk(KERN_foo converted to pr_foo(). -Messages updated to fit in 80 columns. -fs_macros converted as well. -fs_printk removed. Signed-off-by: Fabian Frederick Signed-off-by: Steven Whitehouse

GFS2: Add meta readahead field in directory entries

2014-02-07T11:23:22Z

The intent of this new field in the directory entry is to allow a subsequent lookup to know how many blocks, which are contiguous with the inode, contain metadata which relates to the inode. This will then allow the issuing of a single read to read these blocks, rather than reading the inode first, and then issuing a second read for the metadata. This only works under some fairly strict conditions, since we do not have back pointers from inodes to directory entries we must ensure that the blocks referenced in this way will always belong to the inode. This rules out being able to use this system for indirect blocks, as these can change as a result of truncate/rewrite. So the idea here is to restrict this to xattr blocks only for the time being. For most inodes, that means only a single block. Also, when using ACLs and/or SELinux or other LSMs, these will be added at inode creation time so that they will be contiguous with the inode on disk and also will almost always be needed when we read the inode in for permissions checks. Once an xattr block for an inode is allocated, it will never change until the inode is deallocated. This patch adds the new field, a further patch will add the readahead in due course. Signed-off-by: Steven Whitehouse

GFS2: Add hints to directory leaf blocks

2014-01-08T12:14:57Z

This patch adds four new fields to directory leaf blocks. The intent is not to use them in the kernel itself, although perhaps we may be able to use them as hints at some later date, but instead to provide more information for debug/fsck use. One new field adds a pointer to the inode to which the leaf belongs. This can be useful if the pointer to the leaf block has become corrupt, as it will allow us to know which inode this block should be associated with. This field is set when the leaf is created and never changed over its lifetime. The second field is a "distance from the hash table" field. The meaning is as follows: 0 = An old leaf in which this value has not been set 1 = This leaf is pointed to directly from the hash table 2+ = This leaf is part of a chain, pointed to by another leaf block, the value gives the position in the chain. The third and fourth fields combine to give a time stamp of the most recent directory insertion or deletion from this leaf block. The time stamp is not updated when a new leaf block is chained from the current one. The code is currently written such that the timestamp on the dir inode will match that of the leaf block for the most recent insertion/deletion. For backwards compatibility, any of these new fields which is zero should be considered to be "unknown". Signed-off-by: Steven Whitehouse

GFS2: For exhash conversion, only one block is needed

2014-01-08T11:05:29Z

For most cases, only a single new block is needed when we reach the point of converting from stuffed to exhash directory. The exception being when the file name is so long that it will not fit within the new leaf block. So this patch adds a simple test for that situation so that we do not need to request the full reservation size in this case. Potentially we could calculate more accurately the value to use in other cases too, but that is much more complicated to do and it is doubtful that the benefit would outweigh the extra cost in code complexity. Signed-off-by: Steven Whitehouse

GFS2: Remember directory insert point

2014-01-06T12:49:43Z

When we look to see if there is enough space to add a dir entry without allocation, we have then been repeating the same search later when we do the actual insertion. This patch caches the details of the location in the gfs2_diradd structure, so that we do not have to repeat the search. This will provide a performance improvement which will be greater as the size of the directory increases. Signed-off-by: Steven Whitehouse

GFS2: Add directory addition info structure

2014-01-06T11:28:41Z

The intent is that this structure will hold the information required when adding entries to a directory (linking). To start with, it will contain only the number of blocks which are required to link the new entry into the directory. The current calculation returns either 0 or the maximim number of blocks that can ever be requested by such a transaction. The intent is that in a later patch, we can update the dir code to calculate this value more accurately. In addition further patches will also add further fields to the new structure to increase its utility. In addition this patch fixes a bug where the link used during inode creation was adding requesting too many blocks in some cases. This is harmless unless the fs is close to being full. Signed-off-by: Steven Whitehouse