kernel-ark/fs/adfs/inode.c
Christoph Hellwig a9185b41a4 pass writeback_control to ->write_inode
This gives the filesystem more information about the writeback that
is happening.  Trond requested this for the NFS unstable write handling,
and other filesystems might benefit from this too by beeing able to
distinguish between the different callers in more detail.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 13:25:52 -05:00

383 lines
9.2 KiB
C

/*
* linux/fs/adfs/inode.c
*
* Copyright (C) 1997-1999 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/smp_lock.h>
#include <linux/buffer_head.h>
#include <linux/writeback.h>
#include "adfs.h"
/*
* Lookup/Create a block at offset 'block' into 'inode'. We currently do
* not support creation of new blocks, so we return -EIO for this case.
*/
static int
adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh,
int create)
{
if (!create) {
if (block >= inode->i_blocks)
goto abort_toobig;
block = __adfs_block_map(inode->i_sb, inode->i_ino, block);
if (block)
map_bh(bh, inode->i_sb, block);
return 0;
}
/* don't support allocation of blocks yet */
return -EIO;
abort_toobig:
return 0;
}
static int adfs_writepage(struct page *page, struct writeback_control *wbc)
{
return block_write_full_page(page, adfs_get_block, wbc);
}
static int adfs_readpage(struct file *file, struct page *page)
{
return block_read_full_page(page, adfs_get_block);
}
static int adfs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
*pagep = NULL;
return cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
adfs_get_block,
&ADFS_I(mapping->host)->mmu_private);
}
static sector_t _adfs_bmap(struct address_space *mapping, sector_t block)
{
return generic_block_bmap(mapping, block, adfs_get_block);
}
static const struct address_space_operations adfs_aops = {
.readpage = adfs_readpage,
.writepage = adfs_writepage,
.sync_page = block_sync_page,
.write_begin = adfs_write_begin,
.write_end = generic_write_end,
.bmap = _adfs_bmap
};
static inline unsigned int
adfs_filetype(struct inode *inode)
{
unsigned int type;
if (ADFS_I(inode)->stamped)
type = (ADFS_I(inode)->loadaddr >> 8) & 0xfff;
else
type = (unsigned int) -1;
return type;
}
/*
* Convert ADFS attributes and filetype to Linux permission.
*/
static umode_t
adfs_atts2mode(struct super_block *sb, struct inode *inode)
{
unsigned int filetype, attr = ADFS_I(inode)->attr;
umode_t mode, rmask;
struct adfs_sb_info *asb = ADFS_SB(sb);
if (attr & ADFS_NDA_DIRECTORY) {
mode = S_IRUGO & asb->s_owner_mask;
return S_IFDIR | S_IXUGO | mode;
}
filetype = adfs_filetype(inode);
switch (filetype) {
case 0xfc0: /* LinkFS */
return S_IFLNK|S_IRWXUGO;
case 0xfe6: /* UnixExec */
rmask = S_IRUGO | S_IXUGO;
break;
default:
rmask = S_IRUGO;
}
mode = S_IFREG;
if (attr & ADFS_NDA_OWNER_READ)
mode |= rmask & asb->s_owner_mask;
if (attr & ADFS_NDA_OWNER_WRITE)
mode |= S_IWUGO & asb->s_owner_mask;
if (attr & ADFS_NDA_PUBLIC_READ)
mode |= rmask & asb->s_other_mask;
if (attr & ADFS_NDA_PUBLIC_WRITE)
mode |= S_IWUGO & asb->s_other_mask;
return mode;
}
/*
* Convert Linux permission to ADFS attribute. We try to do the reverse
* of atts2mode, but there is not a 1:1 translation.
*/
static int
adfs_mode2atts(struct super_block *sb, struct inode *inode)
{
umode_t mode;
int attr;
struct adfs_sb_info *asb = ADFS_SB(sb);
/* FIXME: should we be able to alter a link? */
if (S_ISLNK(inode->i_mode))
return ADFS_I(inode)->attr;
if (S_ISDIR(inode->i_mode))
attr = ADFS_NDA_DIRECTORY;
else
attr = 0;
mode = inode->i_mode & asb->s_owner_mask;
if (mode & S_IRUGO)
attr |= ADFS_NDA_OWNER_READ;
if (mode & S_IWUGO)
attr |= ADFS_NDA_OWNER_WRITE;
mode = inode->i_mode & asb->s_other_mask;
mode &= ~asb->s_owner_mask;
if (mode & S_IRUGO)
attr |= ADFS_NDA_PUBLIC_READ;
if (mode & S_IWUGO)
attr |= ADFS_NDA_PUBLIC_WRITE;
return attr;
}
/*
* Convert an ADFS time to Unix time. ADFS has a 40-bit centi-second time
* referenced to 1 Jan 1900 (til 2248)
*/
static void
adfs_adfs2unix_time(struct timespec *tv, struct inode *inode)
{
unsigned int high, low;
if (ADFS_I(inode)->stamped == 0)
goto cur_time;
high = ADFS_I(inode)->loadaddr << 24;
low = ADFS_I(inode)->execaddr;
high |= low >> 8;
low &= 255;
/* Files dated pre 01 Jan 1970 00:00:00. */
if (high < 0x336e996a)
goto too_early;
/* Files dated post 18 Jan 2038 03:14:05. */
if (high >= 0x656e9969)
goto too_late;
/* discard 2208988800 (0x336e996a00) seconds of time */
high -= 0x336e996a;
/* convert 40-bit centi-seconds to 32-bit seconds */
tv->tv_sec = (((high % 100) << 8) + low) / 100 + (high / 100 << 8);
tv->tv_nsec = 0;
return;
cur_time:
*tv = CURRENT_TIME_SEC;
return;
too_early:
tv->tv_sec = tv->tv_nsec = 0;
return;
too_late:
tv->tv_sec = 0x7ffffffd;
tv->tv_nsec = 0;
return;
}
/*
* Convert an Unix time to ADFS time. We only do this if the entry has a
* time/date stamp already.
*/
static void
adfs_unix2adfs_time(struct inode *inode, unsigned int secs)
{
unsigned int high, low;
if (ADFS_I(inode)->stamped) {
/* convert 32-bit seconds to 40-bit centi-seconds */
low = (secs & 255) * 100;
high = (secs / 256) * 100 + (low >> 8) + 0x336e996a;
ADFS_I(inode)->loadaddr = (high >> 24) |
(ADFS_I(inode)->loadaddr & ~0xff);
ADFS_I(inode)->execaddr = (low & 255) | (high << 8);
}
}
/*
* Fill in the inode information from the object information.
*
* Note that this is an inode-less filesystem, so we can't use the inode
* number to reference the metadata on the media. Instead, we use the
* inode number to hold the object ID, which in turn will tell us where
* the data is held. We also save the parent object ID, and with these
* two, we can locate the metadata.
*
* This does mean that we rely on an objects parent remaining the same at
* all times - we cannot cope with a cross-directory rename (yet).
*/
struct inode *
adfs_iget(struct super_block *sb, struct object_info *obj)
{
struct inode *inode;
inode = new_inode(sb);
if (!inode)
goto out;
inode->i_uid = ADFS_SB(sb)->s_uid;
inode->i_gid = ADFS_SB(sb)->s_gid;
inode->i_ino = obj->file_id;
inode->i_size = obj->size;
inode->i_nlink = 2;
inode->i_blocks = (inode->i_size + sb->s_blocksize - 1) >>
sb->s_blocksize_bits;
/*
* we need to save the parent directory ID so that
* write_inode can update the directory information
* for this file. This will need special handling
* for cross-directory renames.
*/
ADFS_I(inode)->parent_id = obj->parent_id;
ADFS_I(inode)->loadaddr = obj->loadaddr;
ADFS_I(inode)->execaddr = obj->execaddr;
ADFS_I(inode)->attr = obj->attr;
ADFS_I(inode)->stamped = ((obj->loadaddr & 0xfff00000) == 0xfff00000);
inode->i_mode = adfs_atts2mode(sb, inode);
adfs_adfs2unix_time(&inode->i_mtime, inode);
inode->i_atime = inode->i_mtime;
inode->i_ctime = inode->i_mtime;
if (S_ISDIR(inode->i_mode)) {
inode->i_op = &adfs_dir_inode_operations;
inode->i_fop = &adfs_dir_operations;
} else if (S_ISREG(inode->i_mode)) {
inode->i_op = &adfs_file_inode_operations;
inode->i_fop = &adfs_file_operations;
inode->i_mapping->a_ops = &adfs_aops;
ADFS_I(inode)->mmu_private = inode->i_size;
}
insert_inode_hash(inode);
out:
return inode;
}
/*
* Validate and convert a changed access mode/time to their ADFS equivalents.
* adfs_write_inode will actually write the information back to the directory
* later.
*/
int
adfs_notify_change(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = dentry->d_inode;
struct super_block *sb = inode->i_sb;
unsigned int ia_valid = attr->ia_valid;
int error;
lock_kernel();
error = inode_change_ok(inode, attr);
/*
* we can't change the UID or GID of any file -
* we have a global UID/GID in the superblock
*/
if ((ia_valid & ATTR_UID && attr->ia_uid != ADFS_SB(sb)->s_uid) ||
(ia_valid & ATTR_GID && attr->ia_gid != ADFS_SB(sb)->s_gid))
error = -EPERM;
if (error)
goto out;
if (ia_valid & ATTR_SIZE)
error = vmtruncate(inode, attr->ia_size);
if (error)
goto out;
if (ia_valid & ATTR_MTIME) {
inode->i_mtime = attr->ia_mtime;
adfs_unix2adfs_time(inode, attr->ia_mtime.tv_sec);
}
/*
* FIXME: should we make these == to i_mtime since we don't
* have the ability to represent them in our filesystem?
*/
if (ia_valid & ATTR_ATIME)
inode->i_atime = attr->ia_atime;
if (ia_valid & ATTR_CTIME)
inode->i_ctime = attr->ia_ctime;
if (ia_valid & ATTR_MODE) {
ADFS_I(inode)->attr = adfs_mode2atts(sb, inode);
inode->i_mode = adfs_atts2mode(sb, inode);
}
/*
* FIXME: should we be marking this inode dirty even if
* we don't have any metadata to write back?
*/
if (ia_valid & (ATTR_SIZE | ATTR_MTIME | ATTR_MODE))
mark_inode_dirty(inode);
out:
unlock_kernel();
return error;
}
/*
* write an existing inode back to the directory, and therefore the disk.
* The adfs-specific inode data has already been updated by
* adfs_notify_change()
*/
int adfs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
struct super_block *sb = inode->i_sb;
struct object_info obj;
int ret;
lock_kernel();
obj.file_id = inode->i_ino;
obj.name_len = 0;
obj.parent_id = ADFS_I(inode)->parent_id;
obj.loadaddr = ADFS_I(inode)->loadaddr;
obj.execaddr = ADFS_I(inode)->execaddr;
obj.attr = ADFS_I(inode)->attr;
obj.size = inode->i_size;
ret = adfs_dir_update(sb, &obj, wbc->sync_mode == WB_SYNC_ALL);
unlock_kernel();
return ret;
}