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OpenCloudOS-Kernel/fs/gfs2/util.c

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[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
[GFS2] Update copyright date to 2006 Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-19 03:09:15 +08:00
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
[GFS2] Update copyright, tidy up incore.h As per comments from Jan Engelhardt <jengelh@linux01.gwdg.de> this updates the copyright message to say "version" in full rather than "v.2". Also incore.h has been updated to remove forward structure declarations which are not required. The gfs2_quota_lvb structure has now had endianess annotations added to it. Also quota.c has been updated so that we now store the lvb data locally in endian independant format to avoid needing a structure in host endianess too. As a result the endianess conversions are done as required at various points and thus the conversion routines in lvb.[ch] are no longer required. I've moved the one remaining constant in lvb.h thats used into lm.h and removed the unused lvb.[ch]. I have not changed the HIF_ constants. That is left to a later patch which I hope will unify the gh_flags and gh_iflags fields of the struct gfs2_holder. Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-01 23:05:15 +08:00
* of the GNU General Public License version 2.
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
*/
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/crc32.h>
[GFS2] Macros removal in gfs2.h As suggested by Pekka Enberg <penberg@cs.helsinki.fi>. The DIV_RU macro is renamed DIV_ROUND_UP and and moved to kernel.h The other macros are gone from gfs2.h as (although not requested by Pekka Enberg) are a number of included header file which are now included individually. The inode number comparison function is now an inline function. The DT2IF and IF2DT may be addressed in a future patch. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-28 06:23:27 +08:00
#include <linux/gfs2_ondisk.h>
[GFS2] Export lm_interface to kernel headers lm_interface.h has a few out of the tree clients such as GFS1 and userland tools. Right now, these clients keeps a copy of the file in their build tree that can go out of sync. Move lm_interface.h to include/linux, export it to userland and clean up fs/gfs2 to use the new location. Signed-off-by: Fabio M. Di Nitto <fabbione@ubuntu.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-19 13:56:29 +08:00
#include <linux/lm_interface.h>
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
#include <asm/uaccess.h>
#include "gfs2.h"
[GFS2] Macros removal in gfs2.h As suggested by Pekka Enberg <penberg@cs.helsinki.fi>. The DIV_RU macro is renamed DIV_ROUND_UP and and moved to kernel.h The other macros are gone from gfs2.h as (although not requested by Pekka Enberg) are a number of included header file which are now included individually. The inode number comparison function is now an inline function. The DT2IF and IF2DT may be addressed in a future patch. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-28 06:23:27 +08:00
#include "incore.h"
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
#include "glock.h"
[GFS2] Macros removal in gfs2.h As suggested by Pekka Enberg <penberg@cs.helsinki.fi>. The DIV_RU macro is renamed DIV_ROUND_UP and and moved to kernel.h The other macros are gone from gfs2.h as (although not requested by Pekka Enberg) are a number of included header file which are now included individually. The inode number comparison function is now an inline function. The DT2IF and IF2DT may be addressed in a future patch. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-28 06:23:27 +08:00
#include "util.h"
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
[PATCH] slab: remove kmem_cache_t Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 12:33:20 +08:00
struct kmem_cache *gfs2_glock_cachep __read_mostly;
struct kmem_cache *gfs2_inode_cachep __read_mostly;
struct kmem_cache *gfs2_bufdata_cachep __read_mostly;
[GFS2] Allocate gfs2_rgrpd from slab memory This patch moves the gfs2_rgrpd structure to its own slab memory. This makes it easier to control and monitor, and yields less memory fragmentation. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-01-29 07:20:26 +08:00
struct kmem_cache *gfs2_rgrpd_cachep __read_mostly;
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
void gfs2_assert_i(struct gfs2_sbd *sdp)
{
printk(KERN_EMERG "GFS2: fsid=%s: fatal assertion failed\n",
sdp->sd_fsname);
}
[GFS2] Remove lm.[ch] and distribute content The functions in lm.c were just wrappers which were mostly only used in one other file. By moving the functions to the files where they are being used, they can be marked static and also this will usually result in them being inlined since they are often only used from one point in the code. A couple of really trivial functions have been inlined by hand into the function which called them as it makes the code clearer to do that. We also gain from one fewer function call in the glock lock and unlock paths. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-01-30 23:34:04 +08:00
int gfs2_lm_withdraw(struct gfs2_sbd *sdp, char *fmt, ...)
{
va_list args;
if (test_and_set_bit(SDF_SHUTDOWN, &sdp->sd_flags))
return 0;
va_start(args, fmt);
vprintk(fmt, args);
va_end(args);
fs_err(sdp, "about to withdraw this file system\n");
BUG_ON(sdp->sd_args.ar_debug);
fs_err(sdp, "telling LM to withdraw\n");
gfs2_withdraw_lockproto(&sdp->sd_lockstruct);
fs_err(sdp, "withdrawn\n");
dump_stack();
return -1;
}
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
/**
* gfs2_assert_withdraw_i - Cause the machine to withdraw if @assertion is false
* Returns: -1 if this call withdrew the machine,
* -2 if it was already withdrawn
*/
int gfs2_assert_withdraw_i(struct gfs2_sbd *sdp, char *assertion,
const char *function, char *file, unsigned int line)
{
int me;
me = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: assertion \"%s\" failed\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname, assertion,
sdp->sd_fsname, function, file, line);
[GFS2] Make journaled data files identical to normal files on disk This is a very large patch, with a few still to be resolved issues so you might want to check out the previous head of the tree since this is known to be unstable. Fixes for the various bugs will be forthcoming shortly. This patch removes the special data format which has been used up till now for journaled data files. Directories still retain the old format so that they will remain on disk compatible with earlier releases. As a result you can now do the following with journaled data files: 1) mmap them 2) export them over NFS 3) convert to/from normal files whenever you want to (the zero length restriction is gone) In addition the level at which GFS' locking is done has changed for all files (since they all now use the page cache) such that the locking is done at the page cache level rather than the level of the fs operations. This should mean that things like loopback mounts and other things which touch the page cache directly should now work. Current known issues: 1. There is a lock mode inversion problem related to the resource group hold function which needs to be resolved. 2. Any significant amount of I/O causes an oops with an offset of hex 320 (NULL pointer dereference) which appears to be related to a journaled data buffer appearing on a list where it shouldn't be. 3. Direct I/O writes are disabled for the time being (will reappear later) 4. There is probably a deadlock between the page lock and GFS' locks under certain combinations of mmap and fs operation I/O. 5. Issue relating to ref counting on internally used inodes causes a hang on umount (discovered before this patch, and not fixed by it) 6. One part of the directory metadata is different from GFS1 and will need to be resolved before next release. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-08 19:50:51 +08:00
dump_stack();
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
return (me) ? -1 : -2;
}
/**
* gfs2_assert_warn_i - Print a message to the console if @assertion is false
* Returns: -1 if we printed something
* -2 if we didn't
*/
int gfs2_assert_warn_i(struct gfs2_sbd *sdp, char *assertion,
const char *function, char *file, unsigned int line)
{
if (time_before(jiffies,
sdp->sd_last_warning +
gfs2_tune_get(sdp, gt_complain_secs) * HZ))
return -2;
printk(KERN_WARNING
"GFS2: fsid=%s: warning: assertion \"%s\" failed\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname, assertion,
sdp->sd_fsname, function, file, line);
if (sdp->sd_args.ar_debug)
BUG();
[GFS2] Make journaled data files identical to normal files on disk This is a very large patch, with a few still to be resolved issues so you might want to check out the previous head of the tree since this is known to be unstable. Fixes for the various bugs will be forthcoming shortly. This patch removes the special data format which has been used up till now for journaled data files. Directories still retain the old format so that they will remain on disk compatible with earlier releases. As a result you can now do the following with journaled data files: 1) mmap them 2) export them over NFS 3) convert to/from normal files whenever you want to (the zero length restriction is gone) In addition the level at which GFS' locking is done has changed for all files (since they all now use the page cache) such that the locking is done at the page cache level rather than the level of the fs operations. This should mean that things like loopback mounts and other things which touch the page cache directly should now work. Current known issues: 1. There is a lock mode inversion problem related to the resource group hold function which needs to be resolved. 2. Any significant amount of I/O causes an oops with an offset of hex 320 (NULL pointer dereference) which appears to be related to a journaled data buffer appearing on a list where it shouldn't be. 3. Direct I/O writes are disabled for the time being (will reappear later) 4. There is probably a deadlock between the page lock and GFS' locks under certain combinations of mmap and fs operation I/O. 5. Issue relating to ref counting on internally used inodes causes a hang on umount (discovered before this patch, and not fixed by it) 6. One part of the directory metadata is different from GFS1 and will need to be resolved before next release. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-02-08 19:50:51 +08:00
else
dump_stack();
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
sdp->sd_last_warning = jiffies;
return -1;
}
/**
* gfs2_consist_i - Flag a filesystem consistency error and withdraw
* Returns: -1 if this call withdrew the machine,
* 0 if it was already withdrawn
*/
int gfs2_consist_i(struct gfs2_sbd *sdp, int cluster_wide, const char *function,
char *file, unsigned int line)
{
int rv;
rv = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: filesystem consistency error\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname,
sdp->sd_fsname, function, file, line);
return rv;
}
/**
* gfs2_consist_inode_i - Flag an inode consistency error and withdraw
* Returns: -1 if this call withdrew the machine,
* 0 if it was already withdrawn
*/
int gfs2_consist_inode_i(struct gfs2_inode *ip, int cluster_wide,
const char *function, char *file, unsigned int line)
{
[GFS2] Fix unlinked file handling This patch fixes the way we have been dealing with unlinked, but still open files. It removes all limits (other than memory for inodes, as per every other filesystem) on numbers of these which we can support on GFS2. It also means that (like other fs) its the responsibility of the last process to close the file to deallocate the storage, rather than the person who did the unlinking. Note that with GFS2, those two events might take place on different nodes. Also there are a number of other changes: o We use the Linux inode subsystem as it was intended to be used, wrt allocating GFS2 inodes o The Linux inode cache is now the point which we use for local enforcement of only holding one copy of the inode in core at once (previous to this we used the glock layer). o We no longer use the unlinked "special" file. We just ignore it completely. This makes unlinking more efficient. o We now use the 4th block allocation state. The previously unused state is used to track unlinked but still open inodes. o gfs2_inoded is no longer needed o Several fields are now no longer needed (and removed) from the in core struct gfs2_inode o Several fields are no longer needed (and removed) from the in core superblock There are a number of future possible optimisations and clean ups which have been made possible by this patch. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-06-15 03:32:57 +08:00
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
int rv;
rv = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: filesystem consistency error\n"
"GFS2: fsid=%s: inode = %llu %llu\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname,
[GFS2] Clean up inode number handling This patch cleans up the inode number handling code. The main difference is that instead of looking up the inodes using a struct gfs2_inum_host we now use just the no_addr member of this structure. The tests relating to no_formal_ino can then be done by the calling code. This has advantages in that we want to do different things in different code paths if the no_formal_ino doesn't match. In the NFS patch we want to return -ESTALE, but in the ->lookup() path, its a bug in the fs if the no_formal_ino doesn't match and thus we can withdraw in this case. In order to later fix bz #201012, we need to be able to look up an inode without knowing no_formal_ino, as the only information that is known to us is the on-disk location of the inode in question. This patch will also help us to fix bz #236099 at a later date by cleaning up a lot of the code in that area. There are no user visible changes as a result of this patch and there are no changes to the on-disk format either. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-05-15 22:37:50 +08:00
sdp->sd_fsname, (unsigned long long)ip->i_no_formal_ino,
(unsigned long long)ip->i_no_addr,
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
sdp->sd_fsname, function, file, line);
return rv;
}
/**
* gfs2_consist_rgrpd_i - Flag a RG consistency error and withdraw
* Returns: -1 if this call withdrew the machine,
* 0 if it was already withdrawn
*/
int gfs2_consist_rgrpd_i(struct gfs2_rgrpd *rgd, int cluster_wide,
const char *function, char *file, unsigned int line)
{
struct gfs2_sbd *sdp = rgd->rd_sbd;
int rv;
rv = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: filesystem consistency error\n"
"GFS2: fsid=%s: RG = %llu\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname,
[GFS2] Fix sign problem in quota/statfs and cleanup _host structures This patch fixes some sign issues which were accidentally introduced into the quota & statfs code during the endianess annotation process. Also included is a general clean up which moves all of the _host structures out of gfs2_ondisk.h (where they should not have been to start with) and into the places where they are actually used (often only one place). Also those _host structures which are not required any more are removed entirely (which is the eventual plan for all of them). The conversion routines from ondisk.c are also moved into the places where they are actually used, which for almost every one, was just one single place, so all those are now static functions. This also cleans up the end of gfs2_ondisk.h which no longer needs the #ifdef __KERNEL__. The net result is a reduction of about 100 lines of code, many functions now marked static plus the bug fixes as mentioned above. For good measure I ran the code through sparse after making these changes to check that there are no warnings generated. This fixes Red Hat bz #239686 Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-06-01 21:11:58 +08:00
sdp->sd_fsname, (unsigned long long)rgd->rd_addr,
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
sdp->sd_fsname, function, file, line);
return rv;
}
/**
* gfs2_meta_check_ii - Flag a magic number consistency error and withdraw
* Returns: -1 if this call withdrew the machine,
* -2 if it was already withdrawn
*/
int gfs2_meta_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
const char *type, const char *function, char *file,
unsigned int line)
{
int me;
me = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: invalid metadata block\n"
"GFS2: fsid=%s: bh = %llu (%s)\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname,
[GFS2] Casts for printing 64bit numbers Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-24 22:22:09 +08:00
sdp->sd_fsname, (unsigned long long)bh->b_blocknr, type,
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
sdp->sd_fsname, function, file, line);
return (me) ? -1 : -2;
}
/**
* gfs2_metatype_check_ii - Flag a metadata type consistency error and withdraw
* Returns: -1 if this call withdrew the machine,
* -2 if it was already withdrawn
*/
int gfs2_metatype_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
[GFS2] Change all types to uX style This makes all fixed size types have consistent names. Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-05 00:49:07 +08:00
u16 type, u16 t, const char *function,
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
char *file, unsigned int line)
{
int me;
me = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: invalid metadata block\n"
"GFS2: fsid=%s: bh = %llu (type: exp=%u, found=%u)\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname,
[GFS2] Casts for printing 64bit numbers Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-24 22:22:09 +08:00
sdp->sd_fsname, (unsigned long long)bh->b_blocknr, type, t,
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
sdp->sd_fsname, function, file, line);
return (me) ? -1 : -2;
}
/**
* gfs2_io_error_i - Flag an I/O error and withdraw
* Returns: -1 if this call withdrew the machine,
* 0 if it was already withdrawn
*/
int gfs2_io_error_i(struct gfs2_sbd *sdp, const char *function, char *file,
unsigned int line)
{
int rv;
rv = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: I/O error\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname,
sdp->sd_fsname, function, file, line);
return rv;
}
/**
* gfs2_io_error_bh_i - Flag a buffer I/O error and withdraw
* Returns: -1 if this call withdrew the machine,
* 0 if it was already withdrawn
*/
int gfs2_io_error_bh_i(struct gfs2_sbd *sdp, struct buffer_head *bh,
const char *function, char *file, unsigned int line)
{
int rv;
rv = gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: fatal: I/O error\n"
"GFS2: fsid=%s: block = %llu\n"
"GFS2: fsid=%s: function = %s, file = %s, line = %u\n",
sdp->sd_fsname,
[GFS2] Casts for printing 64bit numbers Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-24 22:22:09 +08:00
sdp->sd_fsname, (unsigned long long)bh->b_blocknr,
[GFS2] The core of GFS2 This patch contains all the core files for GFS2. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-17 00:50:04 +08:00
sdp->sd_fsname, function, file, line);
return rv;
}
void gfs2_icbit_munge(struct gfs2_sbd *sdp, unsigned char **bitmap,
unsigned int bit, int new_value)
{
unsigned int c, o, b = bit;
int old_value;
c = b / (8 * PAGE_SIZE);
b %= 8 * PAGE_SIZE;
o = b / 8;
b %= 8;
old_value = (bitmap[c][o] & (1 << b));
gfs2_assert_withdraw(sdp, !old_value != !new_value);
if (new_value)
bitmap[c][o] |= 1 << b;
else
bitmap[c][o] &= ~(1 << b);
}