linux/fs/gfs2/ops_file.c
Steven Whitehouse 128e5ebaf8 [GFS2] Remove iflags.h, use FS_
Update GFS2 in the light of David Howells' patch:

[PATCH] BLOCK: Move common FS-specific ioctls to linux/fs.h [try #6]
36695673b0

which calls the filesystem independant flags FS_..._FL. As a result
we no longer need the flags.h file and the conversion routine is
moved into the GFS2 source code.

Userland programs which used to include iflags.h should now include
fs.h and use the new flag names.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-10-02 11:24:43 -04:00

661 lines
15 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/pagemap.h>
#include <linux/uio.h>
#include <linux/blkdev.h>
#include <linux/mm.h>
#include <linux/smp_lock.h>
#include <linux/fs.h>
#include <linux/gfs2_ondisk.h>
#include <linux/ext2_fs.h>
#include <linux/crc32.h>
#include <linux/lm_interface.h>
#include <asm/uaccess.h>
#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "dir.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "lm.h"
#include "log.h"
#include "meta_io.h"
#include "ops_file.h"
#include "ops_vm.h"
#include "quota.h"
#include "rgrp.h"
#include "trans.h"
#include "util.h"
#include "eaops.h"
/* For regular, non-NFS */
struct filldir_reg {
struct gfs2_sbd *fdr_sbd;
int fdr_prefetch;
filldir_t fdr_filldir;
void *fdr_opaque;
};
/*
* Most fields left uninitialised to catch anybody who tries to
* use them. f_flags set to prevent file_accessed() from touching
* any other part of this. Its use is purely as a flag so that we
* know (in readpage()) whether or not do to locking.
*/
struct file gfs2_internal_file_sentinel = {
.f_flags = O_NOATIME|O_RDONLY,
};
static int gfs2_read_actor(read_descriptor_t *desc, struct page *page,
unsigned long offset, unsigned long size)
{
char *kaddr;
unsigned long count = desc->count;
if (size > count)
size = count;
kaddr = kmap(page);
memcpy(desc->arg.buf, kaddr + offset, size);
kunmap(page);
desc->count = count - size;
desc->written += size;
desc->arg.buf += size;
return size;
}
int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state,
char *buf, loff_t *pos, unsigned size)
{
struct inode *inode = &ip->i_inode;
read_descriptor_t desc;
desc.written = 0;
desc.arg.buf = buf;
desc.count = size;
desc.error = 0;
do_generic_mapping_read(inode->i_mapping, ra_state,
&gfs2_internal_file_sentinel, pos, &desc,
gfs2_read_actor);
return desc.written ? desc.written : desc.error;
}
/**
* gfs2_llseek - seek to a location in a file
* @file: the file
* @offset: the offset
* @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
*
* SEEK_END requires the glock for the file because it references the
* file's size.
*
* Returns: The new offset, or errno
*/
static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
{
struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
struct gfs2_holder i_gh;
loff_t error;
if (origin == 2) {
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
&i_gh);
if (!error) {
error = remote_llseek(file, offset, origin);
gfs2_glock_dq_uninit(&i_gh);
}
} else
error = remote_llseek(file, offset, origin);
return error;
}
/**
* filldir_func - Report a directory entry to the caller of gfs2_dir_read()
* @opaque: opaque data used by the function
* @name: the name of the directory entry
* @length: the length of the name
* @offset: the entry's offset in the directory
* @inum: the inode number the entry points to
* @type: the type of inode the entry points to
*
* Returns: 0 on success, 1 if buffer full
*/
static int filldir_func(void *opaque, const char *name, unsigned int length,
u64 offset, struct gfs2_inum *inum,
unsigned int type)
{
struct filldir_reg *fdr = (struct filldir_reg *)opaque;
struct gfs2_sbd *sdp = fdr->fdr_sbd;
int error;
error = fdr->fdr_filldir(fdr->fdr_opaque, name, length, offset,
inum->no_addr, type);
if (error)
return 1;
if (fdr->fdr_prefetch && !(length == 1 && *name == '.')) {
gfs2_glock_prefetch_num(sdp, inum->no_addr, &gfs2_inode_glops,
LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY);
gfs2_glock_prefetch_num(sdp, inum->no_addr, &gfs2_iopen_glops,
LM_ST_SHARED, LM_FLAG_TRY);
}
return 0;
}
/**
* gfs2_readdir - Read directory entries from a directory
* @file: The directory to read from
* @dirent: Buffer for dirents
* @filldir: Function used to do the copying
*
* Returns: errno
*/
static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
{
struct inode *dir = file->f_mapping->host;
struct gfs2_inode *dip = GFS2_I(dir);
struct filldir_reg fdr;
struct gfs2_holder d_gh;
u64 offset = file->f_pos;
int error;
fdr.fdr_sbd = GFS2_SB(dir);
fdr.fdr_prefetch = 1;
fdr.fdr_filldir = filldir;
fdr.fdr_opaque = dirent;
gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
error = gfs2_glock_nq_atime(&d_gh);
if (error) {
gfs2_holder_uninit(&d_gh);
return error;
}
error = gfs2_dir_read(dir, &offset, &fdr, filldir_func);
gfs2_glock_dq_uninit(&d_gh);
file->f_pos = offset;
return error;
}
/**
* fsflags_cvt
* @table: A table of 32 u32 flags
* @val: a 32 bit value to convert
*
* This function can be used to convert between fsflags values and
* GFS2's own flags values.
*
* Returns: the converted flags
*/
static u32 fsflags_cvt(const u32 *table, u32 val)
{
u32 res = 0;
while(val) {
if (val & 1)
res |= *table;
table++;
val >>= 1;
}
return res;
}
static const u32 fsflags_to_gfs2[32] = {
[3] = GFS2_DIF_SYNC,
[4] = GFS2_DIF_IMMUTABLE,
[5] = GFS2_DIF_APPENDONLY,
[7] = GFS2_DIF_NOATIME,
[12] = GFS2_DIF_EXHASH,
[14] = GFS2_DIF_JDATA,
[20] = GFS2_DIF_DIRECTIO,
};
static const u32 gfs2_to_fsflags[32] = {
[gfs2fl_Sync] = FS_SYNC_FL,
[gfs2fl_Immutable] = FS_IMMUTABLE_FL,
[gfs2fl_AppendOnly] = FS_APPEND_FL,
[gfs2fl_NoAtime] = FS_NOATIME_FL,
[gfs2fl_ExHash] = FS_INDEX_FL,
[gfs2fl_Jdata] = FS_JOURNAL_DATA_FL,
[gfs2fl_Directio] = FS_DIRECTIO_FL,
[gfs2fl_InheritDirectio] = FS_DIRECTIO_FL,
[gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL,
};
static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
{
struct inode *inode = filp->f_dentry->d_inode;
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
int error;
u32 fsflags;
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
error = gfs2_glock_nq_m_atime(1, &gh);
if (error)
return error;
fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_di.di_flags);
if (put_user(fsflags, ptr))
error = -EFAULT;
gfs2_glock_dq_m(1, &gh);
gfs2_holder_uninit(&gh);
return error;
}
/* Flags that can be set by user space */
#define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
GFS2_DIF_DIRECTIO| \
GFS2_DIF_IMMUTABLE| \
GFS2_DIF_APPENDONLY| \
GFS2_DIF_NOATIME| \
GFS2_DIF_SYNC| \
GFS2_DIF_SYSTEM| \
GFS2_DIF_INHERIT_DIRECTIO| \
GFS2_DIF_INHERIT_JDATA)
/**
* gfs2_set_flags - set flags on an inode
* @inode: The inode
* @flags: The flags to set
* @mask: Indicates which flags are valid
*
*/
static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
{
struct inode *inode = filp->f_dentry->d_inode;
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
struct buffer_head *bh;
struct gfs2_holder gh;
int error;
u32 new_flags, flags;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
if (error)
return error;
flags = ip->i_di.di_flags;
new_flags = (flags & ~mask) | (reqflags & mask);
if ((new_flags ^ flags) == 0)
goto out;
if (S_ISDIR(inode->i_mode)) {
if ((new_flags ^ flags) & GFS2_DIF_JDATA)
new_flags ^= (GFS2_DIF_JDATA|GFS2_DIF_INHERIT_JDATA);
if ((new_flags ^ flags) & GFS2_DIF_DIRECTIO)
new_flags ^= (GFS2_DIF_DIRECTIO|GFS2_DIF_INHERIT_DIRECTIO);
}
error = -EINVAL;
if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
goto out;
error = -EPERM;
if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
goto out;
if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
goto out;
if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
!capable(CAP_LINUX_IMMUTABLE))
goto out;
if (!IS_IMMUTABLE(inode)) {
error = permission(inode, MAY_WRITE, NULL);
if (error)
goto out;
}
error = gfs2_trans_begin(sdp, RES_DINODE, 0);
if (error)
goto out;
error = gfs2_meta_inode_buffer(ip, &bh);
if (error)
goto out_trans_end;
gfs2_trans_add_bh(ip->i_gl, bh, 1);
ip->i_di.di_flags = new_flags;
gfs2_dinode_out(&ip->i_di, bh->b_data);
brelse(bh);
out_trans_end:
gfs2_trans_end(sdp);
out:
gfs2_glock_dq_uninit(&gh);
return error;
}
static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
{
u32 fsflags, gfsflags;
if (get_user(fsflags, ptr))
return -EFAULT;
gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
return do_gfs2_set_flags(filp, gfsflags, ~0);
}
static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
switch(cmd) {
case FS_IOC_GETFLAGS:
return gfs2_get_flags(filp, (u32 __user *)arg);
case FS_IOC_SETFLAGS:
return gfs2_set_flags(filp, (u32 __user *)arg);
}
return -ENOTTY;
}
/**
* gfs2_mmap -
* @file: The file to map
* @vma: The VMA which described the mapping
*
* Returns: 0 or error code
*/
static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
{
struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
struct gfs2_holder i_gh;
int error;
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
error = gfs2_glock_nq_atime(&i_gh);
if (error) {
gfs2_holder_uninit(&i_gh);
return error;
}
/* This is VM_MAYWRITE instead of VM_WRITE because a call
to mprotect() can turn on VM_WRITE later. */
if ((vma->vm_flags & (VM_MAYSHARE | VM_MAYWRITE)) ==
(VM_MAYSHARE | VM_MAYWRITE))
vma->vm_ops = &gfs2_vm_ops_sharewrite;
else
vma->vm_ops = &gfs2_vm_ops_private;
gfs2_glock_dq_uninit(&i_gh);
return error;
}
/**
* gfs2_open - open a file
* @inode: the inode to open
* @file: the struct file for this opening
*
* Returns: errno
*/
static int gfs2_open(struct inode *inode, struct file *file)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder i_gh;
struct gfs2_file *fp;
int error;
fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
if (!fp)
return -ENOMEM;
mutex_init(&fp->f_fl_mutex);
gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
file->private_data = fp;
if (S_ISREG(ip->i_di.di_mode)) {
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
&i_gh);
if (error)
goto fail;
if (!(file->f_flags & O_LARGEFILE) &&
ip->i_di.di_size > MAX_NON_LFS) {
error = -EFBIG;
goto fail_gunlock;
}
/* Listen to the Direct I/O flag */
if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
file->f_flags |= O_DIRECT;
gfs2_glock_dq_uninit(&i_gh);
}
return 0;
fail_gunlock:
gfs2_glock_dq_uninit(&i_gh);
fail:
file->private_data = NULL;
kfree(fp);
return error;
}
/**
* gfs2_close - called to close a struct file
* @inode: the inode the struct file belongs to
* @file: the struct file being closed
*
* Returns: errno
*/
static int gfs2_close(struct inode *inode, struct file *file)
{
struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
struct gfs2_file *fp;
fp = file->private_data;
file->private_data = NULL;
if (gfs2_assert_warn(sdp, fp))
return -EIO;
kfree(fp);
return 0;
}
/**
* gfs2_fsync - sync the dirty data for a file (across the cluster)
* @file: the file that points to the dentry (we ignore this)
* @dentry: the dentry that points to the inode to sync
*
* Returns: errno
*/
static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync)
{
struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
return 0;
}
/**
* gfs2_lock - acquire/release a posix lock on a file
* @file: the file pointer
* @cmd: either modify or retrieve lock state, possibly wait
* @fl: type and range of lock
*
* Returns: errno
*/
static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
struct lm_lockname name =
{ .ln_number = ip->i_num.no_addr,
.ln_type = LM_TYPE_PLOCK };
if (!(fl->fl_flags & FL_POSIX))
return -ENOLCK;
if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
return -ENOLCK;
if (sdp->sd_args.ar_localflocks) {
if (IS_GETLK(cmd)) {
struct file_lock tmp;
int ret;
ret = posix_test_lock(file, fl, &tmp);
fl->fl_type = F_UNLCK;
if (ret)
memcpy(fl, &tmp, sizeof(struct file_lock));
return 0;
} else {
return posix_lock_file_wait(file, fl);
}
}
if (IS_GETLK(cmd))
return gfs2_lm_plock_get(sdp, &name, file, fl);
else if (fl->fl_type == F_UNLCK)
return gfs2_lm_punlock(sdp, &name, file, fl);
else
return gfs2_lm_plock(sdp, &name, file, cmd, fl);
}
static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_file *fp = file->private_data;
struct gfs2_holder *fl_gh = &fp->f_fl_gh;
struct gfs2_inode *ip = GFS2_I(file->f_dentry->d_inode);
struct gfs2_glock *gl;
unsigned int state;
int flags;
int error = 0;
state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
mutex_lock(&fp->f_fl_mutex);
gl = fl_gh->gh_gl;
if (gl) {
if (fl_gh->gh_state == state)
goto out;
gfs2_glock_hold(gl);
flock_lock_file_wait(file,
&(struct file_lock){.fl_type = F_UNLCK});
gfs2_glock_dq_uninit(fl_gh);
} else {
error = gfs2_glock_get(GFS2_SB(&ip->i_inode),
ip->i_num.no_addr, &gfs2_flock_glops,
CREATE, &gl);
if (error)
goto out;
}
gfs2_holder_init(gl, state, flags, fl_gh);
gfs2_glock_put(gl);
error = gfs2_glock_nq(fl_gh);
if (error) {
gfs2_holder_uninit(fl_gh);
if (error == GLR_TRYFAILED)
error = -EAGAIN;
} else {
error = flock_lock_file_wait(file, fl);
gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
}
out:
mutex_unlock(&fp->f_fl_mutex);
return error;
}
static void do_unflock(struct file *file, struct file_lock *fl)
{
struct gfs2_file *fp = file->private_data;
struct gfs2_holder *fl_gh = &fp->f_fl_gh;
mutex_lock(&fp->f_fl_mutex);
flock_lock_file_wait(file, fl);
if (fl_gh->gh_gl)
gfs2_glock_dq_uninit(fl_gh);
mutex_unlock(&fp->f_fl_mutex);
}
/**
* gfs2_flock - acquire/release a flock lock on a file
* @file: the file pointer
* @cmd: either modify or retrieve lock state, possibly wait
* @fl: type and range of lock
*
* Returns: errno
*/
static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
if (!(fl->fl_flags & FL_FLOCK))
return -ENOLCK;
if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
return -ENOLCK;
if (sdp->sd_args.ar_localflocks)
return flock_lock_file_wait(file, fl);
if (fl->fl_type == F_UNLCK) {
do_unflock(file, fl);
return 0;
} else {
return do_flock(file, cmd, fl);
}
}
const struct file_operations gfs2_file_fops = {
.llseek = gfs2_llseek,
.read = do_sync_read,
.aio_read = generic_file_aio_read,
.write = do_sync_write,
.aio_write = generic_file_aio_write,
.unlocked_ioctl = gfs2_ioctl,
.mmap = gfs2_mmap,
.open = gfs2_open,
.release = gfs2_close,
.fsync = gfs2_fsync,
.lock = gfs2_lock,
.sendfile = generic_file_sendfile,
.flock = gfs2_flock,
.splice_read = generic_file_splice_read,
.splice_write = generic_file_splice_write,
};
const struct file_operations gfs2_dir_fops = {
.readdir = gfs2_readdir,
.unlocked_ioctl = gfs2_ioctl,
.open = gfs2_open,
.release = gfs2_close,
.fsync = gfs2_fsync,
.lock = gfs2_lock,
.flock = gfs2_flock,
};