linux/fs/jffs2/file.c
Matthew Wilcox (Oracle) e9b5b23e95 fs: Change the type of filler_t
By making filler_t the same as read_folio, we can use the same function
for both in gfs2.  We can push the use of folios down one more level
in jffs2 and nfs.  We also increase type safety for future users of the
various read_cache_page() family of functions by forcing the parameter
to be a pointer to struct file (or NULL).

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-05-09 16:36:48 -04:00

343 lines
9.4 KiB
C

/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright © 2001-2007 Red Hat, Inc.
* Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
*
* Created by David Woodhouse <dwmw2@infradead.org>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/crc32.h>
#include <linux/jffs2.h>
#include "nodelist.h"
static int jffs2_write_end(struct file *filp, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *pg, void *fsdata);
static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
loff_t pos, unsigned len,
struct page **pagep, void **fsdata);
static int jffs2_read_folio(struct file *filp, struct folio *folio);
int jffs2_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
{
struct inode *inode = filp->f_mapping->host;
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
int ret;
ret = file_write_and_wait_range(filp, start, end);
if (ret)
return ret;
inode_lock(inode);
/* Trigger GC to flush any pending writes for this inode */
jffs2_flush_wbuf_gc(c, inode->i_ino);
inode_unlock(inode);
return 0;
}
const struct file_operations jffs2_file_operations =
{
.llseek = generic_file_llseek,
.open = generic_file_open,
.read_iter = generic_file_read_iter,
.write_iter = generic_file_write_iter,
.unlocked_ioctl=jffs2_ioctl,
.mmap = generic_file_readonly_mmap,
.fsync = jffs2_fsync,
.splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
};
/* jffs2_file_inode_operations */
const struct inode_operations jffs2_file_inode_operations =
{
.get_acl = jffs2_get_acl,
.set_acl = jffs2_set_acl,
.setattr = jffs2_setattr,
.listxattr = jffs2_listxattr,
};
const struct address_space_operations jffs2_file_address_operations =
{
.read_folio = jffs2_read_folio,
.write_begin = jffs2_write_begin,
.write_end = jffs2_write_end,
};
static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
{
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
unsigned char *pg_buf;
int ret;
jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n",
__func__, inode->i_ino, pg->index << PAGE_SHIFT);
BUG_ON(!PageLocked(pg));
pg_buf = kmap(pg);
/* FIXME: Can kmap fail? */
ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_SHIFT,
PAGE_SIZE);
if (ret) {
ClearPageUptodate(pg);
SetPageError(pg);
} else {
SetPageUptodate(pg);
ClearPageError(pg);
}
flush_dcache_page(pg);
kunmap(pg);
jffs2_dbg(2, "readpage finished\n");
return ret;
}
int __jffs2_read_folio(struct file *file, struct folio *folio)
{
int ret = jffs2_do_readpage_nolock(folio->mapping->host, &folio->page);
folio_unlock(folio);
return ret;
}
static int jffs2_read_folio(struct file *file, struct folio *folio)
{
struct jffs2_inode_info *f = JFFS2_INODE_INFO(folio->mapping->host);
int ret;
mutex_lock(&f->sem);
ret = __jffs2_read_folio(file, folio);
mutex_unlock(&f->sem);
return ret;
}
static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
loff_t pos, unsigned len,
struct page **pagep, void **fsdata)
{
struct page *pg;
struct inode *inode = mapping->host;
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
pgoff_t index = pos >> PAGE_SHIFT;
uint32_t pageofs = index << PAGE_SHIFT;
int ret = 0;
jffs2_dbg(1, "%s()\n", __func__);
if (pageofs > inode->i_size) {
/* Make new hole frag from old EOF to new page */
struct jffs2_raw_inode ri;
struct jffs2_full_dnode *fn;
uint32_t alloc_len;
jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
(unsigned int)inode->i_size, pageofs);
ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
if (ret)
goto out_err;
mutex_lock(&f->sem);
memset(&ri, 0, sizeof(ri));
ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
ri.totlen = cpu_to_je32(sizeof(ri));
ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
ri.ino = cpu_to_je32(f->inocache->ino);
ri.version = cpu_to_je32(++f->highest_version);
ri.mode = cpu_to_jemode(inode->i_mode);
ri.uid = cpu_to_je16(i_uid_read(inode));
ri.gid = cpu_to_je16(i_gid_read(inode));
ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
ri.atime = ri.ctime = ri.mtime = cpu_to_je32(JFFS2_NOW());
ri.offset = cpu_to_je32(inode->i_size);
ri.dsize = cpu_to_je32(pageofs - inode->i_size);
ri.csize = cpu_to_je32(0);
ri.compr = JFFS2_COMPR_ZERO;
ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
ri.data_crc = cpu_to_je32(0);
fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
if (IS_ERR(fn)) {
ret = PTR_ERR(fn);
jffs2_complete_reservation(c);
mutex_unlock(&f->sem);
goto out_err;
}
ret = jffs2_add_full_dnode_to_inode(c, f, fn);
if (f->metadata) {
jffs2_mark_node_obsolete(c, f->metadata->raw);
jffs2_free_full_dnode(f->metadata);
f->metadata = NULL;
}
if (ret) {
jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n",
ret);
jffs2_mark_node_obsolete(c, fn->raw);
jffs2_free_full_dnode(fn);
jffs2_complete_reservation(c);
mutex_unlock(&f->sem);
goto out_err;
}
jffs2_complete_reservation(c);
inode->i_size = pageofs;
mutex_unlock(&f->sem);
}
/*
* While getting a page and reading data in, lock c->alloc_sem until
* the page is Uptodate. Otherwise GC task may attempt to read the same
* page in read_cache_page(), which causes a deadlock.
*/
mutex_lock(&c->alloc_sem);
pg = grab_cache_page_write_begin(mapping, index);
if (!pg) {
ret = -ENOMEM;
goto release_sem;
}
*pagep = pg;
/*
* Read in the page if it wasn't already present. Cannot optimize away
* the whole page write case until jffs2_write_end can handle the
* case of a short-copy.
*/
if (!PageUptodate(pg)) {
mutex_lock(&f->sem);
ret = jffs2_do_readpage_nolock(inode, pg);
mutex_unlock(&f->sem);
if (ret) {
unlock_page(pg);
put_page(pg);
goto release_sem;
}
}
jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags);
release_sem:
mutex_unlock(&c->alloc_sem);
out_err:
return ret;
}
static int jffs2_write_end(struct file *filp, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *pg, void *fsdata)
{
/* Actually commit the write from the page cache page we're looking at.
* For now, we write the full page out each time. It sucks, but it's simple
*/
struct inode *inode = mapping->host;
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
struct jffs2_raw_inode *ri;
unsigned start = pos & (PAGE_SIZE - 1);
unsigned end = start + copied;
unsigned aligned_start = start & ~3;
int ret = 0;
uint32_t writtenlen = 0;
jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
__func__, inode->i_ino, pg->index << PAGE_SHIFT,
start, end, pg->flags);
/* We need to avoid deadlock with page_cache_read() in
jffs2_garbage_collect_pass(). So the page must be
up to date to prevent page_cache_read() from trying
to re-lock it. */
BUG_ON(!PageUptodate(pg));
if (end == PAGE_SIZE) {
/* When writing out the end of a page, write out the
_whole_ page. This helps to reduce the number of
nodes in files which have many short writes, like
syslog files. */
aligned_start = 0;
}
ri = jffs2_alloc_raw_inode();
if (!ri) {
jffs2_dbg(1, "%s(): Allocation of raw inode failed\n",
__func__);
unlock_page(pg);
put_page(pg);
return -ENOMEM;
}
/* Set the fields that the generic jffs2_write_inode_range() code can't find */
ri->ino = cpu_to_je32(inode->i_ino);
ri->mode = cpu_to_jemode(inode->i_mode);
ri->uid = cpu_to_je16(i_uid_read(inode));
ri->gid = cpu_to_je16(i_gid_read(inode));
ri->isize = cpu_to_je32((uint32_t)inode->i_size);
ri->atime = ri->ctime = ri->mtime = cpu_to_je32(JFFS2_NOW());
/* In 2.4, it was already kmapped by generic_file_write(). Doesn't
hurt to do it again. The alternative is ifdefs, which are ugly. */
kmap(pg);
ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
(pg->index << PAGE_SHIFT) + aligned_start,
end - aligned_start, &writtenlen);
kunmap(pg);
if (ret) {
/* There was an error writing. */
SetPageError(pg);
}
/* Adjust writtenlen for the padding we did, so we don't confuse our caller */
writtenlen -= min(writtenlen, (start - aligned_start));
if (writtenlen) {
if (inode->i_size < pos + writtenlen) {
inode->i_size = pos + writtenlen;
inode->i_blocks = (inode->i_size + 511) >> 9;
inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
}
}
jffs2_free_raw_inode(ri);
if (start+writtenlen < end) {
/* generic_file_write has written more to the page cache than we've
actually written to the medium. Mark the page !Uptodate so that
it gets reread */
jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n",
__func__);
SetPageError(pg);
ClearPageUptodate(pg);
}
jffs2_dbg(1, "%s() returning %d\n",
__func__, writtenlen > 0 ? writtenlen : ret);
unlock_page(pg);
put_page(pg);
return writtenlen > 0 ? writtenlen : ret;
}