mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-06 02:56:44 +07:00
2b0143b5c9
that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
286 lines
7.2 KiB
C
286 lines
7.2 KiB
C
/*
|
|
* fs/logfs/file.c - prepare_write, commit_write and friends
|
|
*
|
|
* As should be obvious for Linux kernel code, license is GPLv2
|
|
*
|
|
* Copyright (c) 2005-2008 Joern Engel <joern@logfs.org>
|
|
*/
|
|
#include "logfs.h"
|
|
#include <linux/sched.h>
|
|
#include <linux/writeback.h>
|
|
|
|
static int logfs_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
struct page *page;
|
|
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
|
|
|
|
page = grab_cache_page_write_begin(mapping, index, flags);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
*pagep = page;
|
|
|
|
if ((len == PAGE_CACHE_SIZE) || PageUptodate(page))
|
|
return 0;
|
|
if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
|
|
unsigned start = pos & (PAGE_CACHE_SIZE - 1);
|
|
unsigned end = start + len;
|
|
|
|
/* Reading beyond i_size is simple: memset to zero */
|
|
zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
|
|
return 0;
|
|
}
|
|
return logfs_readpage_nolock(page);
|
|
}
|
|
|
|
static int logfs_write_end(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied, struct page *page,
|
|
void *fsdata)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
pgoff_t index = page->index;
|
|
unsigned start = pos & (PAGE_CACHE_SIZE - 1);
|
|
unsigned end = start + copied;
|
|
int ret = 0;
|
|
|
|
BUG_ON(PAGE_CACHE_SIZE != inode->i_sb->s_blocksize);
|
|
BUG_ON(page->index > I3_BLOCKS);
|
|
|
|
if (copied < len) {
|
|
/*
|
|
* Short write of a non-initialized paged. Just tell userspace
|
|
* to retry the entire page.
|
|
*/
|
|
if (!PageUptodate(page)) {
|
|
copied = 0;
|
|
goto out;
|
|
}
|
|
}
|
|
if (copied == 0)
|
|
goto out; /* FIXME: do we need to update inode? */
|
|
|
|
if (i_size_read(inode) < (index << PAGE_CACHE_SHIFT) + end) {
|
|
i_size_write(inode, (index << PAGE_CACHE_SHIFT) + end);
|
|
mark_inode_dirty_sync(inode);
|
|
}
|
|
|
|
SetPageUptodate(page);
|
|
if (!PageDirty(page)) {
|
|
if (!get_page_reserve(inode, page))
|
|
__set_page_dirty_nobuffers(page);
|
|
else
|
|
ret = logfs_write_buf(inode, page, WF_LOCK);
|
|
}
|
|
out:
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
int logfs_readpage(struct file *file, struct page *page)
|
|
{
|
|
int ret;
|
|
|
|
ret = logfs_readpage_nolock(page);
|
|
unlock_page(page);
|
|
return ret;
|
|
}
|
|
|
|
/* Clear the page's dirty flag in the radix tree. */
|
|
/* TODO: mucking with PageWriteback is silly. Add a generic function to clear
|
|
* the dirty bit from the radix tree for filesystems that don't have to wait
|
|
* for page writeback to finish (i.e. any compressing filesystem).
|
|
*/
|
|
static void clear_radix_tree_dirty(struct page *page)
|
|
{
|
|
BUG_ON(PagePrivate(page) || page->private);
|
|
set_page_writeback(page);
|
|
end_page_writeback(page);
|
|
}
|
|
|
|
static int __logfs_writepage(struct page *page)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
int err;
|
|
|
|
err = logfs_write_buf(inode, page, WF_LOCK);
|
|
if (err)
|
|
set_page_dirty(page);
|
|
else
|
|
clear_radix_tree_dirty(page);
|
|
unlock_page(page);
|
|
return err;
|
|
}
|
|
|
|
static int logfs_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
loff_t i_size = i_size_read(inode);
|
|
pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
|
|
unsigned offset;
|
|
u64 bix;
|
|
level_t level;
|
|
|
|
log_file("logfs_writepage(%lx, %lx, %p)\n", inode->i_ino, page->index,
|
|
page);
|
|
|
|
logfs_unpack_index(page->index, &bix, &level);
|
|
|
|
/* Indirect blocks are never truncated */
|
|
if (level != 0)
|
|
return __logfs_writepage(page);
|
|
|
|
/*
|
|
* TODO: everything below is a near-verbatim copy of nobh_writepage().
|
|
* The relevant bits should be factored out after logfs is merged.
|
|
*/
|
|
|
|
/* Is the page fully inside i_size? */
|
|
if (bix < end_index)
|
|
return __logfs_writepage(page);
|
|
|
|
/* Is the page fully outside i_size? (truncate in progress) */
|
|
offset = i_size & (PAGE_CACHE_SIZE-1);
|
|
if (bix > end_index || offset == 0) {
|
|
unlock_page(page);
|
|
return 0; /* don't care */
|
|
}
|
|
|
|
/*
|
|
* The page straddles i_size. It must be zeroed out on each and every
|
|
* writepage invokation because it may be mmapped. "A file is mapped
|
|
* in multiples of the page size. For a file that is not a multiple of
|
|
* the page size, the remaining memory is zeroed when mapped, and
|
|
* writes to that region are not written out to the file."
|
|
*/
|
|
zero_user_segment(page, offset, PAGE_CACHE_SIZE);
|
|
return __logfs_writepage(page);
|
|
}
|
|
|
|
static void logfs_invalidatepage(struct page *page, unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
struct logfs_block *block = logfs_block(page);
|
|
|
|
if (block->reserved_bytes) {
|
|
struct super_block *sb = page->mapping->host->i_sb;
|
|
struct logfs_super *super = logfs_super(sb);
|
|
|
|
super->s_dirty_pages -= block->reserved_bytes;
|
|
block->ops->free_block(sb, block);
|
|
BUG_ON(bitmap_weight(block->alias_map, LOGFS_BLOCK_FACTOR));
|
|
} else
|
|
move_page_to_btree(page);
|
|
BUG_ON(PagePrivate(page) || page->private);
|
|
}
|
|
|
|
static int logfs_releasepage(struct page *page, gfp_t only_xfs_uses_this)
|
|
{
|
|
return 0; /* None of these are easy to release */
|
|
}
|
|
|
|
|
|
long logfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct logfs_inode *li = logfs_inode(inode);
|
|
unsigned int oldflags, flags;
|
|
int err;
|
|
|
|
switch (cmd) {
|
|
case FS_IOC_GETFLAGS:
|
|
flags = li->li_flags & LOGFS_FL_USER_VISIBLE;
|
|
return put_user(flags, (int __user *)arg);
|
|
case FS_IOC_SETFLAGS:
|
|
if (IS_RDONLY(inode))
|
|
return -EROFS;
|
|
|
|
if (!inode_owner_or_capable(inode))
|
|
return -EACCES;
|
|
|
|
err = get_user(flags, (int __user *)arg);
|
|
if (err)
|
|
return err;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
oldflags = li->li_flags;
|
|
flags &= LOGFS_FL_USER_MODIFIABLE;
|
|
flags |= oldflags & ~LOGFS_FL_USER_MODIFIABLE;
|
|
li->li_flags = flags;
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
inode->i_ctime = CURRENT_TIME;
|
|
mark_inode_dirty_sync(inode);
|
|
return 0;
|
|
|
|
default:
|
|
return -ENOTTY;
|
|
}
|
|
}
|
|
|
|
int logfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
|
|
{
|
|
struct super_block *sb = file->f_mapping->host->i_sb;
|
|
struct inode *inode = file->f_mapping->host;
|
|
int ret;
|
|
|
|
ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
|
|
if (ret)
|
|
return ret;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
logfs_get_wblocks(sb, NULL, WF_LOCK);
|
|
logfs_write_anchor(sb);
|
|
logfs_put_wblocks(sb, NULL, WF_LOCK);
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int logfs_setattr(struct dentry *dentry, struct iattr *attr)
|
|
{
|
|
struct inode *inode = d_inode(dentry);
|
|
int err = 0;
|
|
|
|
err = inode_change_ok(inode, attr);
|
|
if (err)
|
|
return err;
|
|
|
|
if (attr->ia_valid & ATTR_SIZE) {
|
|
err = logfs_truncate(inode, attr->ia_size);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
setattr_copy(inode, attr);
|
|
mark_inode_dirty(inode);
|
|
return 0;
|
|
}
|
|
|
|
const struct inode_operations logfs_reg_iops = {
|
|
.setattr = logfs_setattr,
|
|
};
|
|
|
|
const struct file_operations logfs_reg_fops = {
|
|
.read_iter = generic_file_read_iter,
|
|
.write_iter = generic_file_write_iter,
|
|
.fsync = logfs_fsync,
|
|
.unlocked_ioctl = logfs_ioctl,
|
|
.llseek = generic_file_llseek,
|
|
.mmap = generic_file_readonly_mmap,
|
|
.open = generic_file_open,
|
|
};
|
|
|
|
const struct address_space_operations logfs_reg_aops = {
|
|
.invalidatepage = logfs_invalidatepage,
|
|
.readpage = logfs_readpage,
|
|
.releasepage = logfs_releasepage,
|
|
.set_page_dirty = __set_page_dirty_nobuffers,
|
|
.writepage = logfs_writepage,
|
|
.writepages = generic_writepages,
|
|
.write_begin = logfs_write_begin,
|
|
.write_end = logfs_write_end,
|
|
};
|