![Linus Torvalds](/assets/img/avatar_default.png)
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
824 lines
20 KiB
C
824 lines
20 KiB
C
/*
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* $Id: blkmtd.c,v 1.24 2004/11/16 18:29:01 dwmw2 Exp $
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*
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* blkmtd.c - use a block device as a fake MTD
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*
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* Author: Simon Evans <spse@secret.org.uk>
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*
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* Copyright (C) 2001,2002 Simon Evans
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*
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* Licence: GPL
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*
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* How it works:
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* The driver uses raw/io to read/write the device and the page
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* cache to cache access. Writes update the page cache with the
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* new data and mark it dirty and add the page into a BIO which
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* is then written out.
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*
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* It can be loaded Read-Only to prevent erases and writes to the
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* medium.
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*
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*/
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#include <linux/config.h>
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/blkdev.h>
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#include <linux/bio.h>
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#include <linux/pagemap.h>
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#include <linux/list.h>
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#include <linux/init.h>
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#include <linux/mtd/mtd.h>
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#define err(format, arg...) printk(KERN_ERR "blkmtd: " format "\n" , ## arg)
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#define info(format, arg...) printk(KERN_INFO "blkmtd: " format "\n" , ## arg)
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#define warn(format, arg...) printk(KERN_WARNING "blkmtd: " format "\n" , ## arg)
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#define crit(format, arg...) printk(KERN_CRIT "blkmtd: " format "\n" , ## arg)
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/* Default erase size in K, always make it a multiple of PAGE_SIZE */
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#define CONFIG_MTD_BLKDEV_ERASESIZE (128 << 10) /* 128KiB */
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#define VERSION "$Revision: 1.24 $"
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/* Info for the block device */
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struct blkmtd_dev {
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struct list_head list;
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struct block_device *blkdev;
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struct mtd_info mtd_info;
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struct semaphore wrbuf_mutex;
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};
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/* Static info about the MTD, used in cleanup_module */
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static LIST_HEAD(blkmtd_device_list);
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static void blkmtd_sync(struct mtd_info *mtd);
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#define MAX_DEVICES 4
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/* Module parameters passed by insmod/modprobe */
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static char *device[MAX_DEVICES]; /* the block device to use */
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static int erasesz[MAX_DEVICES]; /* optional default erase size */
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static int ro[MAX_DEVICES]; /* optional read only flag */
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static int sync;
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Simon Evans <spse@secret.org.uk>");
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MODULE_DESCRIPTION("Emulate an MTD using a block device");
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module_param_array(device, charp, NULL, 0);
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MODULE_PARM_DESC(device, "block device to use");
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module_param_array(erasesz, int, NULL, 0);
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MODULE_PARM_DESC(erasesz, "optional erase size to use in KiB. eg 4=4KiB.");
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module_param_array(ro, bool, NULL, 0);
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MODULE_PARM_DESC(ro, "1=Read only, writes and erases cause errors");
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module_param(sync, bool, 0);
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MODULE_PARM_DESC(sync, "1=Synchronous writes");
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/* completion handler for BIO reads */
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static int bi_read_complete(struct bio *bio, unsigned int bytes_done, int error)
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{
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if (bio->bi_size)
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return 1;
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complete((struct completion*)bio->bi_private);
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return 0;
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}
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/* completion handler for BIO writes */
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static int bi_write_complete(struct bio *bio, unsigned int bytes_done, int error)
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{
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const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
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struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
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if (bio->bi_size)
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return 1;
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if(!uptodate)
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err("bi_write_complete: not uptodate\n");
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do {
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struct page *page = bvec->bv_page;
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DEBUG(3, "Cleaning up page %ld\n", page->index);
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if (--bvec >= bio->bi_io_vec)
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prefetchw(&bvec->bv_page->flags);
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if (uptodate) {
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SetPageUptodate(page);
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} else {
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ClearPageUptodate(page);
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SetPageError(page);
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}
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ClearPageDirty(page);
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unlock_page(page);
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page_cache_release(page);
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} while (bvec >= bio->bi_io_vec);
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complete((struct completion*)bio->bi_private);
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return 0;
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}
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/* read one page from the block device */
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static int blkmtd_readpage(struct blkmtd_dev *dev, struct page *page)
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{
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struct bio *bio;
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struct completion event;
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int err = -ENOMEM;
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if(PageUptodate(page)) {
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DEBUG(2, "blkmtd: readpage page %ld is already upto date\n", page->index);
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unlock_page(page);
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return 0;
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}
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ClearPageUptodate(page);
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ClearPageError(page);
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bio = bio_alloc(GFP_KERNEL, 1);
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if(bio) {
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init_completion(&event);
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bio->bi_bdev = dev->blkdev;
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bio->bi_sector = page->index << (PAGE_SHIFT-9);
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bio->bi_private = &event;
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bio->bi_end_io = bi_read_complete;
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if(bio_add_page(bio, page, PAGE_SIZE, 0) == PAGE_SIZE) {
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submit_bio(READ_SYNC, bio);
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wait_for_completion(&event);
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err = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : -EIO;
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bio_put(bio);
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}
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}
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if(err)
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SetPageError(page);
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else
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SetPageUptodate(page);
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flush_dcache_page(page);
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unlock_page(page);
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return err;
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}
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/* write out the current BIO and wait for it to finish */
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static int blkmtd_write_out(struct bio *bio)
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{
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struct completion event;
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int err;
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if(!bio->bi_vcnt) {
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bio_put(bio);
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return 0;
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}
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init_completion(&event);
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bio->bi_private = &event;
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bio->bi_end_io = bi_write_complete;
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submit_bio(WRITE_SYNC, bio);
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wait_for_completion(&event);
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DEBUG(3, "submit_bio completed, bi_vcnt = %d\n", bio->bi_vcnt);
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err = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : -EIO;
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bio_put(bio);
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return err;
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}
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/**
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* blkmtd_add_page - add a page to the current BIO
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* @bio: bio to add to (NULL to alloc initial bio)
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* @blkdev: block device
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* @page: page to add
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* @pagecnt: pages left to add
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*
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* Adds a page to the current bio, allocating it if necessary. If it cannot be
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* added, the current bio is written out and a new one is allocated. Returns
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* the new bio to add or NULL on error
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*/
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static struct bio *blkmtd_add_page(struct bio *bio, struct block_device *blkdev,
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struct page *page, int pagecnt)
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{
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retry:
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if(!bio) {
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bio = bio_alloc(GFP_KERNEL, pagecnt);
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if(!bio)
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return NULL;
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bio->bi_sector = page->index << (PAGE_SHIFT-9);
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bio->bi_bdev = blkdev;
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}
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if(bio_add_page(bio, page, PAGE_SIZE, 0) != PAGE_SIZE) {
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blkmtd_write_out(bio);
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bio = NULL;
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goto retry;
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}
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return bio;
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}
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/**
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* write_pages - write block of data to device via the page cache
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* @dev: device to write to
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* @buf: data source or NULL if erase (output is set to 0xff)
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* @to: offset into output device
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* @len: amount to data to write
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* @retlen: amount of data written
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*
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* Grab pages from the page cache and fill them with the source data.
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* Non page aligned start and end result in a readin of the page and
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* part of the page being modified. Pages are added to the bio and then written
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* out.
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*/
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static int write_pages(struct blkmtd_dev *dev, const u_char *buf, loff_t to,
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size_t len, size_t *retlen)
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{
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int pagenr, offset;
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size_t start_len = 0, end_len;
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int pagecnt = 0;
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int err = 0;
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struct bio *bio = NULL;
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size_t thislen = 0;
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pagenr = to >> PAGE_SHIFT;
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offset = to & ~PAGE_MASK;
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DEBUG(2, "blkmtd: write_pages: buf = %p to = %ld len = %zd pagenr = %d offset = %d\n",
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buf, (long)to, len, pagenr, offset);
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/* see if we have to do a partial write at the start */
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if(offset) {
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start_len = ((offset + len) > PAGE_SIZE) ? PAGE_SIZE - offset : len;
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len -= start_len;
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}
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/* calculate the length of the other two regions */
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end_len = len & ~PAGE_MASK;
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len -= end_len;
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if(start_len)
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pagecnt++;
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if(len)
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pagecnt += len >> PAGE_SHIFT;
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if(end_len)
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pagecnt++;
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down(&dev->wrbuf_mutex);
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DEBUG(3, "blkmtd: write: start_len = %zd len = %zd end_len = %zd pagecnt = %d\n",
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start_len, len, end_len, pagecnt);
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if(start_len) {
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/* do partial start region */
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struct page *page;
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DEBUG(3, "blkmtd: write: doing partial start, page = %d len = %zd offset = %d\n",
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pagenr, start_len, offset);
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BUG_ON(!buf);
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page = read_cache_page(dev->blkdev->bd_inode->i_mapping, pagenr, (filler_t *)blkmtd_readpage, dev);
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lock_page(page);
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if(PageDirty(page)) {
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err("to = %lld start_len = %zd len = %zd end_len = %zd pagenr = %d\n",
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to, start_len, len, end_len, pagenr);
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BUG();
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}
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memcpy(page_address(page)+offset, buf, start_len);
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SetPageDirty(page);
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SetPageUptodate(page);
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buf += start_len;
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thislen = start_len;
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bio = blkmtd_add_page(bio, dev->blkdev, page, pagecnt);
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if(!bio) {
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err = -ENOMEM;
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err("bio_add_page failed\n");
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goto write_err;
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}
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pagecnt--;
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pagenr++;
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}
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/* Now do the main loop to a page aligned, n page sized output */
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if(len) {
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int pagesc = len >> PAGE_SHIFT;
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DEBUG(3, "blkmtd: write: whole pages start = %d, count = %d\n",
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pagenr, pagesc);
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while(pagesc) {
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struct page *page;
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/* see if page is in the page cache */
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DEBUG(3, "blkmtd: write: grabbing page %d from page cache\n", pagenr);
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page = grab_cache_page(dev->blkdev->bd_inode->i_mapping, pagenr);
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if(PageDirty(page)) {
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BUG();
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}
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if(!page) {
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warn("write: cannot grab cache page %d", pagenr);
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err = -ENOMEM;
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goto write_err;
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}
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if(!buf) {
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memset(page_address(page), 0xff, PAGE_SIZE);
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} else {
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memcpy(page_address(page), buf, PAGE_SIZE);
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buf += PAGE_SIZE;
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}
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bio = blkmtd_add_page(bio, dev->blkdev, page, pagecnt);
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if(!bio) {
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err = -ENOMEM;
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err("bio_add_page failed\n");
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goto write_err;
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}
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pagenr++;
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pagecnt--;
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SetPageDirty(page);
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SetPageUptodate(page);
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pagesc--;
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thislen += PAGE_SIZE;
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}
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}
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if(end_len) {
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/* do the third region */
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struct page *page;
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DEBUG(3, "blkmtd: write: doing partial end, page = %d len = %zd\n",
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pagenr, end_len);
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BUG_ON(!buf);
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page = read_cache_page(dev->blkdev->bd_inode->i_mapping, pagenr, (filler_t *)blkmtd_readpage, dev);
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lock_page(page);
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if(PageDirty(page)) {
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err("to = %lld start_len = %zd len = %zd end_len = %zd pagenr = %d\n",
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to, start_len, len, end_len, pagenr);
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BUG();
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}
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memcpy(page_address(page), buf, end_len);
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SetPageDirty(page);
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SetPageUptodate(page);
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DEBUG(3, "blkmtd: write: writing out partial end\n");
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thislen += end_len;
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bio = blkmtd_add_page(bio, dev->blkdev, page, pagecnt);
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if(!bio) {
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err = -ENOMEM;
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err("bio_add_page failed\n");
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goto write_err;
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}
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pagenr++;
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}
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DEBUG(3, "blkmtd: write: got %d vectors to write\n", bio->bi_vcnt);
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write_err:
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if(bio)
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blkmtd_write_out(bio);
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DEBUG(2, "blkmtd: write: end, retlen = %zd, err = %d\n", *retlen, err);
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up(&dev->wrbuf_mutex);
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if(retlen)
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*retlen = thislen;
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return err;
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}
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/* erase a specified part of the device */
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static int blkmtd_erase(struct mtd_info *mtd, struct erase_info *instr)
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{
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struct blkmtd_dev *dev = mtd->priv;
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struct mtd_erase_region_info *einfo = mtd->eraseregions;
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int numregions = mtd->numeraseregions;
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size_t from;
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u_long len;
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int err = -EIO;
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size_t retlen;
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instr->state = MTD_ERASING;
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from = instr->addr;
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len = instr->len;
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/* check erase region has valid start and length */
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DEBUG(2, "blkmtd: erase: dev = `%s' from = 0x%zx len = 0x%lx\n",
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mtd->name+9, from, len);
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while(numregions) {
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DEBUG(3, "blkmtd: checking erase region = 0x%08X size = 0x%X num = 0x%x\n",
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einfo->offset, einfo->erasesize, einfo->numblocks);
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if(from >= einfo->offset
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&& from < einfo->offset + (einfo->erasesize * einfo->numblocks)) {
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if(len == einfo->erasesize
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&& ( (from - einfo->offset) % einfo->erasesize == 0))
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break;
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}
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numregions--;
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einfo++;
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}
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if(!numregions) {
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/* Not a valid erase block */
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err("erase: invalid erase request 0x%lX @ 0x%08zX", len, from);
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instr->state = MTD_ERASE_FAILED;
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err = -EIO;
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}
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if(instr->state != MTD_ERASE_FAILED) {
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/* do the erase */
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DEBUG(3, "Doing erase from = %zd len = %ld\n", from, len);
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err = write_pages(dev, NULL, from, len, &retlen);
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if(err || retlen != len) {
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err("erase failed err = %d", err);
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instr->state = MTD_ERASE_FAILED;
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} else {
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instr->state = MTD_ERASE_DONE;
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}
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}
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|
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DEBUG(3, "blkmtd: erase: checking callback\n");
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mtd_erase_callback(instr);
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DEBUG(2, "blkmtd: erase: finished (err = %d)\n", err);
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return err;
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}
|
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|
|
|
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/* read a range of the data via the page cache */
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static int blkmtd_read(struct mtd_info *mtd, loff_t from, size_t len,
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size_t *retlen, u_char *buf)
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{
|
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struct blkmtd_dev *dev = mtd->priv;
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int err = 0;
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int offset;
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int pagenr, pages;
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size_t thislen = 0;
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DEBUG(2, "blkmtd: read: dev = `%s' from = %lld len = %zd buf = %p\n",
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mtd->name+9, from, len, buf);
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|
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if(from > mtd->size)
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return -EINVAL;
|
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if(from + len > mtd->size)
|
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len = mtd->size - from;
|
|
|
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pagenr = from >> PAGE_SHIFT;
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offset = from - (pagenr << PAGE_SHIFT);
|
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|
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pages = (offset+len+PAGE_SIZE-1) >> PAGE_SHIFT;
|
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DEBUG(3, "blkmtd: read: pagenr = %d offset = %d, pages = %d\n",
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pagenr, offset, pages);
|
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|
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while(pages) {
|
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struct page *page;
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int cpylen;
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DEBUG(3, "blkmtd: read: looking for page: %d\n", pagenr);
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page = read_cache_page(dev->blkdev->bd_inode->i_mapping, pagenr, (filler_t *)blkmtd_readpage, dev);
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if(IS_ERR(page)) {
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err = -EIO;
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goto readerr;
|
|
}
|
|
|
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cpylen = (PAGE_SIZE > len) ? len : PAGE_SIZE;
|
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if(offset+cpylen > PAGE_SIZE)
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cpylen = PAGE_SIZE-offset;
|
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|
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memcpy(buf + thislen, page_address(page) + offset, cpylen);
|
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offset = 0;
|
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len -= cpylen;
|
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thislen += cpylen;
|
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pagenr++;
|
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pages--;
|
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if(!PageDirty(page))
|
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page_cache_release(page);
|
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}
|
|
|
|
readerr:
|
|
if(retlen)
|
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*retlen = thislen;
|
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DEBUG(2, "blkmtd: end read: retlen = %zd, err = %d\n", thislen, err);
|
|
return err;
|
|
}
|
|
|
|
|
|
/* write data to the underlying device */
|
|
static int blkmtd_write(struct mtd_info *mtd, loff_t to, size_t len,
|
|
size_t *retlen, const u_char *buf)
|
|
{
|
|
struct blkmtd_dev *dev = mtd->priv;
|
|
int err;
|
|
|
|
if(!len)
|
|
return 0;
|
|
|
|
DEBUG(2, "blkmtd: write: dev = `%s' to = %lld len = %zd buf = %p\n",
|
|
mtd->name+9, to, len, buf);
|
|
|
|
if(to >= mtd->size) {
|
|
return -ENOSPC;
|
|
}
|
|
|
|
if(to + len > mtd->size) {
|
|
len = mtd->size - to;
|
|
}
|
|
|
|
err = write_pages(dev, buf, to, len, retlen);
|
|
if(err > 0)
|
|
err = 0;
|
|
DEBUG(2, "blkmtd: write: end, err = %d\n", err);
|
|
return err;
|
|
}
|
|
|
|
|
|
/* sync the device - wait until the write queue is empty */
|
|
static void blkmtd_sync(struct mtd_info *mtd)
|
|
{
|
|
/* Currently all writes are synchronous */
|
|
}
|
|
|
|
|
|
static void free_device(struct blkmtd_dev *dev)
|
|
{
|
|
DEBUG(2, "blkmtd: free_device() dev = %p\n", dev);
|
|
if(dev) {
|
|
if(dev->mtd_info.eraseregions)
|
|
kfree(dev->mtd_info.eraseregions);
|
|
if(dev->mtd_info.name)
|
|
kfree(dev->mtd_info.name);
|
|
|
|
if(dev->blkdev) {
|
|
invalidate_inode_pages(dev->blkdev->bd_inode->i_mapping);
|
|
close_bdev_excl(dev->blkdev);
|
|
}
|
|
kfree(dev);
|
|
}
|
|
}
|
|
|
|
|
|
/* For a given size and initial erase size, calculate the number
|
|
* and size of each erase region. Goes round the loop twice,
|
|
* once to find out how many regions, then allocates space,
|
|
* then round the loop again to fill it in.
|
|
*/
|
|
static struct mtd_erase_region_info *calc_erase_regions(
|
|
size_t erase_size, size_t total_size, int *regions)
|
|
{
|
|
struct mtd_erase_region_info *info = NULL;
|
|
|
|
DEBUG(2, "calc_erase_regions, es = %zd size = %zd regions = %d\n",
|
|
erase_size, total_size, *regions);
|
|
/* Make any user specified erasesize be a power of 2
|
|
and at least PAGE_SIZE */
|
|
if(erase_size) {
|
|
int es = erase_size;
|
|
erase_size = 1;
|
|
while(es != 1) {
|
|
es >>= 1;
|
|
erase_size <<= 1;
|
|
}
|
|
if(erase_size < PAGE_SIZE)
|
|
erase_size = PAGE_SIZE;
|
|
} else {
|
|
erase_size = CONFIG_MTD_BLKDEV_ERASESIZE;
|
|
}
|
|
|
|
*regions = 0;
|
|
|
|
do {
|
|
int tot_size = total_size;
|
|
int er_size = erase_size;
|
|
int count = 0, offset = 0, regcnt = 0;
|
|
|
|
while(tot_size) {
|
|
count = tot_size / er_size;
|
|
if(count) {
|
|
tot_size = tot_size % er_size;
|
|
if(info) {
|
|
DEBUG(2, "adding to erase info off=%d er=%d cnt=%d\n",
|
|
offset, er_size, count);
|
|
(info+regcnt)->offset = offset;
|
|
(info+regcnt)->erasesize = er_size;
|
|
(info+regcnt)->numblocks = count;
|
|
(*regions)++;
|
|
}
|
|
regcnt++;
|
|
offset += (count * er_size);
|
|
}
|
|
while(er_size > tot_size)
|
|
er_size >>= 1;
|
|
}
|
|
if(info == NULL) {
|
|
info = kmalloc(regcnt * sizeof(struct mtd_erase_region_info), GFP_KERNEL);
|
|
if(!info)
|
|
break;
|
|
}
|
|
} while(!(*regions));
|
|
DEBUG(2, "calc_erase_regions done, es = %zd size = %zd regions = %d\n",
|
|
erase_size, total_size, *regions);
|
|
return info;
|
|
}
|
|
|
|
|
|
extern dev_t __init name_to_dev_t(const char *line);
|
|
|
|
static struct blkmtd_dev *add_device(char *devname, int readonly, int erase_size)
|
|
{
|
|
struct block_device *bdev;
|
|
int mode;
|
|
struct blkmtd_dev *dev;
|
|
|
|
if(!devname)
|
|
return NULL;
|
|
|
|
/* Get a handle on the device */
|
|
|
|
|
|
#ifdef MODULE
|
|
mode = (readonly) ? O_RDONLY : O_RDWR;
|
|
bdev = open_bdev_excl(devname, mode, NULL);
|
|
#else
|
|
mode = (readonly) ? FMODE_READ : FMODE_WRITE;
|
|
bdev = open_by_devnum(name_to_dev_t(devname), mode);
|
|
#endif
|
|
if(IS_ERR(bdev)) {
|
|
err("error: cannot open device %s", devname);
|
|
DEBUG(2, "blkmtd: opening bdev returned %ld\n", PTR_ERR(bdev));
|
|
return NULL;
|
|
}
|
|
|
|
DEBUG(1, "blkmtd: found a block device major = %d, minor = %d\n",
|
|
MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
|
|
|
|
if(MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
|
|
err("attempting to use an MTD device as a block device");
|
|
blkdev_put(bdev);
|
|
return NULL;
|
|
}
|
|
|
|
dev = kmalloc(sizeof(struct blkmtd_dev), GFP_KERNEL);
|
|
if(dev == NULL) {
|
|
blkdev_put(bdev);
|
|
return NULL;
|
|
}
|
|
|
|
memset(dev, 0, sizeof(struct blkmtd_dev));
|
|
dev->blkdev = bdev;
|
|
if(!readonly) {
|
|
init_MUTEX(&dev->wrbuf_mutex);
|
|
}
|
|
|
|
dev->mtd_info.size = dev->blkdev->bd_inode->i_size & PAGE_MASK;
|
|
|
|
/* Setup the MTD structure */
|
|
/* make the name contain the block device in */
|
|
dev->mtd_info.name = kmalloc(sizeof("blkmtd: ") + strlen(devname), GFP_KERNEL);
|
|
if(dev->mtd_info.name == NULL)
|
|
goto devinit_err;
|
|
|
|
sprintf(dev->mtd_info.name, "blkmtd: %s", devname);
|
|
dev->mtd_info.eraseregions = calc_erase_regions(erase_size, dev->mtd_info.size,
|
|
&dev->mtd_info.numeraseregions);
|
|
if(dev->mtd_info.eraseregions == NULL)
|
|
goto devinit_err;
|
|
|
|
dev->mtd_info.erasesize = dev->mtd_info.eraseregions->erasesize;
|
|
DEBUG(1, "blkmtd: init: found %d erase regions\n",
|
|
dev->mtd_info.numeraseregions);
|
|
|
|
if(readonly) {
|
|
dev->mtd_info.type = MTD_ROM;
|
|
dev->mtd_info.flags = MTD_CAP_ROM;
|
|
} else {
|
|
dev->mtd_info.type = MTD_RAM;
|
|
dev->mtd_info.flags = MTD_CAP_RAM;
|
|
dev->mtd_info.erase = blkmtd_erase;
|
|
dev->mtd_info.write = blkmtd_write;
|
|
dev->mtd_info.writev = default_mtd_writev;
|
|
dev->mtd_info.sync = blkmtd_sync;
|
|
}
|
|
dev->mtd_info.read = blkmtd_read;
|
|
dev->mtd_info.readv = default_mtd_readv;
|
|
dev->mtd_info.priv = dev;
|
|
dev->mtd_info.owner = THIS_MODULE;
|
|
|
|
list_add(&dev->list, &blkmtd_device_list);
|
|
if (add_mtd_device(&dev->mtd_info)) {
|
|
/* Device didnt get added, so free the entry */
|
|
list_del(&dev->list);
|
|
goto devinit_err;
|
|
} else {
|
|
info("mtd%d: [%s] erase_size = %dKiB %s",
|
|
dev->mtd_info.index, dev->mtd_info.name + strlen("blkmtd: "),
|
|
dev->mtd_info.erasesize >> 10,
|
|
readonly ? "(read-only)" : "");
|
|
}
|
|
|
|
return dev;
|
|
|
|
devinit_err:
|
|
free_device(dev);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/* Cleanup and exit - sync the device and kill of the kernel thread */
|
|
static void __devexit cleanup_blkmtd(void)
|
|
{
|
|
struct list_head *temp1, *temp2;
|
|
|
|
/* Remove the MTD devices */
|
|
list_for_each_safe(temp1, temp2, &blkmtd_device_list) {
|
|
struct blkmtd_dev *dev = list_entry(temp1, struct blkmtd_dev,
|
|
list);
|
|
blkmtd_sync(&dev->mtd_info);
|
|
del_mtd_device(&dev->mtd_info);
|
|
info("mtd%d: [%s] removed", dev->mtd_info.index,
|
|
dev->mtd_info.name + strlen("blkmtd: "));
|
|
list_del(&dev->list);
|
|
free_device(dev);
|
|
}
|
|
}
|
|
|
|
#ifndef MODULE
|
|
|
|
/* Handle kernel boot params */
|
|
|
|
|
|
static int __init param_blkmtd_device(char *str)
|
|
{
|
|
int i;
|
|
|
|
for(i = 0; i < MAX_DEVICES; i++) {
|
|
device[i] = str;
|
|
DEBUG(2, "blkmtd: device setup: %d = %s\n", i, device[i]);
|
|
strsep(&str, ",");
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
|
|
static int __init param_blkmtd_erasesz(char *str)
|
|
{
|
|
int i;
|
|
for(i = 0; i < MAX_DEVICES; i++) {
|
|
char *val = strsep(&str, ",");
|
|
if(val)
|
|
erasesz[i] = simple_strtoul(val, NULL, 0);
|
|
DEBUG(2, "blkmtd: erasesz setup: %d = %d\n", i, erasesz[i]);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
|
|
static int __init param_blkmtd_ro(char *str)
|
|
{
|
|
int i;
|
|
for(i = 0; i < MAX_DEVICES; i++) {
|
|
char *val = strsep(&str, ",");
|
|
if(val)
|
|
ro[i] = simple_strtoul(val, NULL, 0);
|
|
DEBUG(2, "blkmtd: ro setup: %d = %d\n", i, ro[i]);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
|
|
static int __init param_blkmtd_sync(char *str)
|
|
{
|
|
if(str[0] == '1')
|
|
sync = 1;
|
|
return 1;
|
|
}
|
|
|
|
__setup("blkmtd_device=", param_blkmtd_device);
|
|
__setup("blkmtd_erasesz=", param_blkmtd_erasesz);
|
|
__setup("blkmtd_ro=", param_blkmtd_ro);
|
|
__setup("blkmtd_sync=", param_blkmtd_sync);
|
|
|
|
#endif
|
|
|
|
|
|
/* Startup */
|
|
static int __init init_blkmtd(void)
|
|
{
|
|
int i;
|
|
|
|
info("version " VERSION);
|
|
/* Check args - device[0] is the bare minimum*/
|
|
if(!device[0]) {
|
|
err("error: missing `device' name\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
for(i = 0; i < MAX_DEVICES; i++)
|
|
add_device(device[i], ro[i], erasesz[i] << 10);
|
|
|
|
if(list_empty(&blkmtd_device_list))
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
module_init(init_blkmtd);
|
|
module_exit(cleanup_blkmtd);
|