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Diffstat (limited to 'fs/logfs/dev_bdev.c')
-rw-r--r--fs/logfs/dev_bdev.c290
1 files changed, 0 insertions, 290 deletions
diff --git a/fs/logfs/dev_bdev.c b/fs/logfs/dev_bdev.c
deleted file mode 100644
index 9bfa0151d7c9..000000000000
--- a/fs/logfs/dev_bdev.c
+++ /dev/null
@@ -1,290 +0,0 @@
-/*
- * fs/logfs/dev_bdev.c - Device access methods for block devices
- *
- * 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/bio.h>
-#include <linux/blkdev.h>
-#include <linux/buffer_head.h>
-#include <linux/gfp.h>
-#include <linux/prefetch.h>
-
-#define PAGE_OFS(ofs) ((ofs) & (PAGE_SIZE-1))
-
-static int sync_request(struct page *page, struct block_device *bdev, int op)
-{
- struct bio bio;
- struct bio_vec bio_vec;
-
- bio_init(&bio, &bio_vec, 1);
- bio.bi_bdev = bdev;
- bio_add_page(&bio, page, PAGE_SIZE, 0);
- bio.bi_iter.bi_sector = page->index * (PAGE_SIZE >> 9);
- bio_set_op_attrs(&bio, op, 0);
-
- return submit_bio_wait(&bio);
-}
-
-static int bdev_readpage(void *_sb, struct page *page)
-{
- struct super_block *sb = _sb;
- struct block_device *bdev = logfs_super(sb)->s_bdev;
- int err;
-
- err = sync_request(page, bdev, READ);
- if (err) {
- ClearPageUptodate(page);
- SetPageError(page);
- } else {
- SetPageUptodate(page);
- ClearPageError(page);
- }
- unlock_page(page);
- return err;
-}
-
-static DECLARE_WAIT_QUEUE_HEAD(wq);
-
-static void writeseg_end_io(struct bio *bio)
-{
- struct bio_vec *bvec;
- int i;
- struct super_block *sb = bio->bi_private;
- struct logfs_super *super = logfs_super(sb);
-
- BUG_ON(bio->bi_error); /* FIXME: Retry io or write elsewhere */
-
- bio_for_each_segment_all(bvec, bio, i) {
- end_page_writeback(bvec->bv_page);
- put_page(bvec->bv_page);
- }
- bio_put(bio);
- if (atomic_dec_and_test(&super->s_pending_writes))
- wake_up(&wq);
-}
-
-static int __bdev_writeseg(struct super_block *sb, u64 ofs, pgoff_t index,
- size_t nr_pages)
-{
- struct logfs_super *super = logfs_super(sb);
- struct address_space *mapping = super->s_mapping_inode->i_mapping;
- struct bio *bio = NULL;
- struct page *page;
- unsigned int max_pages;
- int i, ret;
-
- max_pages = min_t(size_t, nr_pages, BIO_MAX_PAGES);
-
- for (i = 0; i < nr_pages; i++) {
- if (!bio) {
- bio = bio_alloc(GFP_NOFS, max_pages);
- BUG_ON(!bio);
-
- bio->bi_bdev = super->s_bdev;
- bio->bi_iter.bi_sector = ofs >> 9;
- bio->bi_private = sb;
- bio->bi_end_io = writeseg_end_io;
- bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
- }
- page = find_lock_page(mapping, index + i);
- BUG_ON(!page);
- ret = bio_add_page(bio, page, PAGE_SIZE, 0);
-
- BUG_ON(PageWriteback(page));
- set_page_writeback(page);
- unlock_page(page);
-
- if (!ret) {
- /* Block layer cannot split bios :( */
- ofs += bio->bi_iter.bi_size;
- atomic_inc(&super->s_pending_writes);
- submit_bio(bio);
- bio = NULL;
- }
- }
-
- if (bio) {
- atomic_inc(&super->s_pending_writes);
- submit_bio(bio);
- }
- return 0;
-}
-
-static void bdev_writeseg(struct super_block *sb, u64 ofs, size_t len)
-{
- struct logfs_super *super = logfs_super(sb);
- int head;
-
- BUG_ON(super->s_flags & LOGFS_SB_FLAG_RO);
-
- if (len == 0) {
- /* This can happen when the object fit perfectly into a
- * segment, the segment gets written per sync and subsequently
- * closed.
- */
- return;
- }
- head = ofs & (PAGE_SIZE - 1);
- if (head) {
- ofs -= head;
- len += head;
- }
- len = PAGE_ALIGN(len);
- __bdev_writeseg(sb, ofs, ofs >> PAGE_SHIFT, len >> PAGE_SHIFT);
-}
-
-
-static void erase_end_io(struct bio *bio)
-{
- struct super_block *sb = bio->bi_private;
- struct logfs_super *super = logfs_super(sb);
-
- BUG_ON(bio->bi_error); /* FIXME: Retry io or write elsewhere */
- bio_put(bio);
- if (atomic_dec_and_test(&super->s_pending_writes))
- wake_up(&wq);
-}
-
-static int do_erase(struct super_block *sb, u64 ofs, pgoff_t index,
- size_t nr_pages)
-{
- struct logfs_super *super = logfs_super(sb);
- struct bio *bio = NULL;
- unsigned int max_pages;
- int i, ret;
-
- max_pages = min_t(size_t, nr_pages, BIO_MAX_PAGES);
-
- for (i = 0; i < nr_pages; i++) {
- if (!bio) {
- bio = bio_alloc(GFP_NOFS, max_pages);
- BUG_ON(!bio);
-
- bio->bi_bdev = super->s_bdev;
- bio->bi_iter.bi_sector = ofs >> 9;
- bio->bi_private = sb;
- bio->bi_end_io = erase_end_io;
- bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
- }
- ret = bio_add_page(bio, super->s_erase_page, PAGE_SIZE, 0);
- if (!ret) {
- /* Block layer cannot split bios :( */
- ofs += bio->bi_iter.bi_size;
- atomic_inc(&super->s_pending_writes);
- submit_bio(bio);
- }
- }
- if (bio) {
- atomic_inc(&super->s_pending_writes);
- submit_bio(bio);
- }
- return 0;
-}
-
-static int bdev_erase(struct super_block *sb, loff_t to, size_t len,
- int ensure_write)
-{
- struct logfs_super *super = logfs_super(sb);
-
- BUG_ON(to & (PAGE_SIZE - 1));
- BUG_ON(len & (PAGE_SIZE - 1));
-
- if (super->s_flags & LOGFS_SB_FLAG_RO)
- return -EROFS;
-
- if (ensure_write) {
- /*
- * Object store doesn't care whether erases happen or not.
- * But for the journal they are required. Otherwise a scan
- * can find an old commit entry and assume it is the current
- * one, travelling back in time.
- */
- do_erase(sb, to, to >> PAGE_SHIFT, len >> PAGE_SHIFT);
- }
-
- return 0;
-}
-
-static void bdev_sync(struct super_block *sb)
-{
- struct logfs_super *super = logfs_super(sb);
-
- wait_event(wq, atomic_read(&super->s_pending_writes) == 0);
-}
-
-static struct page *bdev_find_first_sb(struct super_block *sb, u64 *ofs)
-{
- struct logfs_super *super = logfs_super(sb);
- struct address_space *mapping = super->s_mapping_inode->i_mapping;
- filler_t *filler = bdev_readpage;
-
- *ofs = 0;
- return read_cache_page(mapping, 0, filler, sb);
-}
-
-static struct page *bdev_find_last_sb(struct super_block *sb, u64 *ofs)
-{
- struct logfs_super *super = logfs_super(sb);
- struct address_space *mapping = super->s_mapping_inode->i_mapping;
- filler_t *filler = bdev_readpage;
- u64 pos = (super->s_bdev->bd_inode->i_size & ~0xfffULL) - 0x1000;
- pgoff_t index = pos >> PAGE_SHIFT;
-
- *ofs = pos;
- return read_cache_page(mapping, index, filler, sb);
-}
-
-static int bdev_write_sb(struct super_block *sb, struct page *page)
-{
- struct block_device *bdev = logfs_super(sb)->s_bdev;
-
- /* Nothing special to do for block devices. */
- return sync_request(page, bdev, WRITE);
-}
-
-static void bdev_put_device(struct logfs_super *s)
-{
- blkdev_put(s->s_bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
-}
-
-static int bdev_can_write_buf(struct super_block *sb, u64 ofs)
-{
- return 0;
-}
-
-static const struct logfs_device_ops bd_devops = {
- .find_first_sb = bdev_find_first_sb,
- .find_last_sb = bdev_find_last_sb,
- .write_sb = bdev_write_sb,
- .readpage = bdev_readpage,
- .writeseg = bdev_writeseg,
- .erase = bdev_erase,
- .can_write_buf = bdev_can_write_buf,
- .sync = bdev_sync,
- .put_device = bdev_put_device,
-};
-
-int logfs_get_sb_bdev(struct logfs_super *p, struct file_system_type *type,
- const char *devname)
-{
- struct block_device *bdev;
-
- bdev = blkdev_get_by_path(devname, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
- type);
- if (IS_ERR(bdev))
- return PTR_ERR(bdev);
-
- if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
- int mtdnr = MINOR(bdev->bd_dev);
- blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
- return logfs_get_sb_mtd(p, mtdnr);
- }
-
- p->s_bdev = bdev;
- p->s_mtd = NULL;
- p->s_devops = &bd_devops;
- return 0;
-}
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-25 14:50:48 +0000