1659 lines
43 KiB
C
1659 lines
43 KiB
C
/*
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* bitmap.c two-level bitmap (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
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*
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* bitmap_create - sets up the bitmap structure
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* bitmap_destroy - destroys the bitmap structure
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*
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* additions, Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.:
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* - added disk storage for bitmap
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* - changes to allow various bitmap chunk sizes
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* - added bitmap daemon (to asynchronously clear bitmap bits from disk)
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*/
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/*
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* Still to do:
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*
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* flush after percent set rather than just time based. (maybe both).
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* wait if count gets too high, wake when it drops to half.
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* allow bitmap to be mirrored with superblock (before or after...)
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* allow hot-add to re-instate a current device.
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* allow hot-add of bitmap after quiessing device
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*/
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#include <linux/module.h>
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#include <linux/version.h>
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <linux/init.h>
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#include <linux/config.h>
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#include <linux/timer.h>
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#include <linux/sched.h>
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#include <linux/list.h>
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#include <linux/file.h>
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#include <linux/mount.h>
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#include <linux/buffer_head.h>
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#include <linux/raid/md.h>
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#include <linux/raid/bitmap.h>
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/* debug macros */
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#define DEBUG 0
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#if DEBUG
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/* these are for debugging purposes only! */
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/* define one and only one of these */
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#define INJECT_FAULTS_1 0 /* cause bitmap_alloc_page to fail always */
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#define INJECT_FAULTS_2 0 /* cause bitmap file to be kicked when first bit set*/
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#define INJECT_FAULTS_3 0 /* treat bitmap file as kicked at init time */
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#define INJECT_FAULTS_4 0 /* undef */
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#define INJECT_FAULTS_5 0 /* undef */
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#define INJECT_FAULTS_6 0
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/* if these are defined, the driver will fail! debug only */
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#define INJECT_FATAL_FAULT_1 0 /* fail kmalloc, causing bitmap_create to fail */
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#define INJECT_FATAL_FAULT_2 0 /* undef */
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#define INJECT_FATAL_FAULT_3 0 /* undef */
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#endif
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//#define DPRINTK PRINTK /* set this NULL to avoid verbose debug output */
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#define DPRINTK(x...) do { } while(0)
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#ifndef PRINTK
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# if DEBUG > 0
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# define PRINTK(x...) printk(KERN_DEBUG x)
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# else
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# define PRINTK(x...)
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# endif
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#endif
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static inline char * bmname(struct bitmap *bitmap)
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{
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return bitmap->mddev ? mdname(bitmap->mddev) : "mdX";
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}
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/*
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* test if the bitmap is active
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*/
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int bitmap_active(struct bitmap *bitmap)
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{
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unsigned long flags;
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int res = 0;
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if (!bitmap)
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return res;
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spin_lock_irqsave(&bitmap->lock, flags);
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res = bitmap->flags & BITMAP_ACTIVE;
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spin_unlock_irqrestore(&bitmap->lock, flags);
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return res;
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}
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#define WRITE_POOL_SIZE 256
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/* mempool for queueing pending writes on the bitmap file */
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static void *write_pool_alloc(unsigned int gfp_flags, void *data)
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{
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return kmalloc(sizeof(struct page_list), gfp_flags);
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}
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static void write_pool_free(void *ptr, void *data)
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{
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kfree(ptr);
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}
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/*
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* just a placeholder - calls kmalloc for bitmap pages
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*/
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static unsigned char *bitmap_alloc_page(struct bitmap *bitmap)
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{
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unsigned char *page;
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#ifdef INJECT_FAULTS_1
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page = NULL;
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#else
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page = kmalloc(PAGE_SIZE, GFP_NOIO);
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#endif
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if (!page)
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printk("%s: bitmap_alloc_page FAILED\n", bmname(bitmap));
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else
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PRINTK("%s: bitmap_alloc_page: allocated page at %p\n",
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bmname(bitmap), page);
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return page;
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}
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/*
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* for now just a placeholder -- just calls kfree for bitmap pages
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*/
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static void bitmap_free_page(struct bitmap *bitmap, unsigned char *page)
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{
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PRINTK("%s: bitmap_free_page: free page %p\n", bmname(bitmap), page);
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kfree(page);
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}
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/*
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* check a page and, if necessary, allocate it (or hijack it if the alloc fails)
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*
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* 1) check to see if this page is allocated, if it's not then try to alloc
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* 2) if the alloc fails, set the page's hijacked flag so we'll use the
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* page pointer directly as a counter
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*
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* if we find our page, we increment the page's refcount so that it stays
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* allocated while we're using it
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*/
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static int bitmap_checkpage(struct bitmap *bitmap, unsigned long page, int create)
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{
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unsigned char *mappage;
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if (page >= bitmap->pages) {
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printk(KERN_ALERT
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"%s: invalid bitmap page request: %lu (> %lu)\n",
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bmname(bitmap), page, bitmap->pages-1);
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return -EINVAL;
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}
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if (bitmap->bp[page].hijacked) /* it's hijacked, don't try to alloc */
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return 0;
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if (bitmap->bp[page].map) /* page is already allocated, just return */
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return 0;
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if (!create)
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return -ENOENT;
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spin_unlock_irq(&bitmap->lock);
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/* this page has not been allocated yet */
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if ((mappage = bitmap_alloc_page(bitmap)) == NULL) {
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PRINTK("%s: bitmap map page allocation failed, hijacking\n",
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bmname(bitmap));
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/* failed - set the hijacked flag so that we can use the
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* pointer as a counter */
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spin_lock_irq(&bitmap->lock);
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if (!bitmap->bp[page].map)
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bitmap->bp[page].hijacked = 1;
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goto out;
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}
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/* got a page */
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spin_lock_irq(&bitmap->lock);
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/* recheck the page */
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if (bitmap->bp[page].map || bitmap->bp[page].hijacked) {
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/* somebody beat us to getting the page */
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bitmap_free_page(bitmap, mappage);
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return 0;
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}
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/* no page was in place and we have one, so install it */
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memset(mappage, 0, PAGE_SIZE);
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bitmap->bp[page].map = mappage;
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bitmap->missing_pages--;
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out:
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return 0;
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}
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/* if page is completely empty, put it back on the free list, or dealloc it */
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/* if page was hijacked, unmark the flag so it might get alloced next time */
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/* Note: lock should be held when calling this */
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static inline void bitmap_checkfree(struct bitmap *bitmap, unsigned long page)
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{
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char *ptr;
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if (bitmap->bp[page].count) /* page is still busy */
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return;
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/* page is no longer in use, it can be released */
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if (bitmap->bp[page].hijacked) { /* page was hijacked, undo this now */
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bitmap->bp[page].hijacked = 0;
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bitmap->bp[page].map = NULL;
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return;
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}
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/* normal case, free the page */
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#if 0
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/* actually ... let's not. We will probably need the page again exactly when
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* memory is tight and we are flusing to disk
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*/
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return;
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#else
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ptr = bitmap->bp[page].map;
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bitmap->bp[page].map = NULL;
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bitmap->missing_pages++;
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bitmap_free_page(bitmap, ptr);
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return;
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#endif
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}
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/*
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* bitmap file handling - read and write the bitmap file and its superblock
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*/
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/* copy the pathname of a file to a buffer */
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char *file_path(struct file *file, char *buf, int count)
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{
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struct dentry *d;
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struct vfsmount *v;
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if (!buf)
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return NULL;
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d = file->f_dentry;
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v = file->f_vfsmnt;
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buf = d_path(d, v, buf, count);
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return IS_ERR(buf) ? NULL : buf;
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}
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/*
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* basic page I/O operations
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*/
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/* IO operations when bitmap is stored near all superblocks */
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static struct page *read_sb_page(mddev_t *mddev, long offset, unsigned long index)
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{
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/* choose a good rdev and read the page from there */
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mdk_rdev_t *rdev;
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struct list_head *tmp;
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struct page *page = alloc_page(GFP_KERNEL);
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sector_t target;
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if (!page)
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return ERR_PTR(-ENOMEM);
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ITERATE_RDEV(mddev, rdev, tmp) {
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if (! rdev->in_sync || rdev->faulty)
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continue;
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target = (rdev->sb_offset << 1) + offset + index * (PAGE_SIZE/512);
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if (sync_page_io(rdev->bdev, target, PAGE_SIZE, page, READ)) {
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page->index = index;
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return page;
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}
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}
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return ERR_PTR(-EIO);
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}
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static int write_sb_page(mddev_t *mddev, long offset, struct page *page, int wait)
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{
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mdk_rdev_t *rdev;
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struct list_head *tmp;
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ITERATE_RDEV(mddev, rdev, tmp)
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if (rdev->in_sync && !rdev->faulty)
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md_super_write(mddev, rdev,
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(rdev->sb_offset<<1) + offset
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+ page->index * (PAGE_SIZE/512),
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PAGE_SIZE,
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page);
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if (wait)
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wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
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return 0;
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}
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/*
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* write out a page to a file
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*/
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static int write_page(struct bitmap *bitmap, struct page *page, int wait)
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{
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int ret = -ENOMEM;
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if (bitmap->file == NULL)
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return write_sb_page(bitmap->mddev, bitmap->offset, page, wait);
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if (wait)
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lock_page(page);
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else {
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if (TestSetPageLocked(page))
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return -EAGAIN; /* already locked */
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if (PageWriteback(page)) {
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unlock_page(page);
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return -EAGAIN;
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}
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}
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ret = page->mapping->a_ops->prepare_write(NULL, page, 0, PAGE_SIZE);
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if (!ret)
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ret = page->mapping->a_ops->commit_write(NULL, page, 0,
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PAGE_SIZE);
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if (ret) {
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unlock_page(page);
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return ret;
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}
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set_page_dirty(page); /* force it to be written out */
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if (!wait) {
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/* add to list to be waited for by daemon */
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struct page_list *item = mempool_alloc(bitmap->write_pool, GFP_NOIO);
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item->page = page;
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page_cache_get(page);
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spin_lock(&bitmap->write_lock);
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list_add(&item->list, &bitmap->complete_pages);
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spin_unlock(&bitmap->write_lock);
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md_wakeup_thread(bitmap->writeback_daemon);
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}
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return write_one_page(page, wait);
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}
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/* read a page from a file, pinning it into cache, and return bytes_read */
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static struct page *read_page(struct file *file, unsigned long index,
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unsigned long *bytes_read)
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{
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struct inode *inode = file->f_mapping->host;
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struct page *page = NULL;
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loff_t isize = i_size_read(inode);
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unsigned long end_index = isize >> PAGE_CACHE_SHIFT;
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PRINTK("read bitmap file (%dB @ %Lu)\n", (int)PAGE_CACHE_SIZE,
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(unsigned long long)index << PAGE_CACHE_SHIFT);
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page = read_cache_page(inode->i_mapping, index,
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(filler_t *)inode->i_mapping->a_ops->readpage, file);
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if (IS_ERR(page))
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goto out;
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wait_on_page_locked(page);
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if (!PageUptodate(page) || PageError(page)) {
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page_cache_release(page);
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page = ERR_PTR(-EIO);
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goto out;
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}
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if (index > end_index) /* we have read beyond EOF */
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*bytes_read = 0;
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else if (index == end_index) /* possible short read */
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*bytes_read = isize & ~PAGE_CACHE_MASK;
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else
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*bytes_read = PAGE_CACHE_SIZE; /* got a full page */
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out:
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if (IS_ERR(page))
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printk(KERN_ALERT "md: bitmap read error: (%dB @ %Lu): %ld\n",
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(int)PAGE_CACHE_SIZE,
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(unsigned long long)index << PAGE_CACHE_SHIFT,
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PTR_ERR(page));
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return page;
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}
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/*
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* bitmap file superblock operations
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*/
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/* update the event counter and sync the superblock to disk */
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int bitmap_update_sb(struct bitmap *bitmap)
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{
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bitmap_super_t *sb;
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unsigned long flags;
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if (!bitmap || !bitmap->mddev) /* no bitmap for this array */
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return 0;
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spin_lock_irqsave(&bitmap->lock, flags);
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if (!bitmap->sb_page) { /* no superblock */
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spin_unlock_irqrestore(&bitmap->lock, flags);
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return 0;
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}
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spin_unlock_irqrestore(&bitmap->lock, flags);
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sb = (bitmap_super_t *)kmap(bitmap->sb_page);
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sb->events = cpu_to_le64(bitmap->mddev->events);
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if (!bitmap->mddev->degraded)
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sb->events_cleared = cpu_to_le64(bitmap->mddev->events);
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kunmap(bitmap->sb_page);
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return write_page(bitmap, bitmap->sb_page, 1);
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}
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/* print out the bitmap file superblock */
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void bitmap_print_sb(struct bitmap *bitmap)
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{
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bitmap_super_t *sb;
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if (!bitmap || !bitmap->sb_page)
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return;
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sb = (bitmap_super_t *)kmap(bitmap->sb_page);
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printk(KERN_DEBUG "%s: bitmap file superblock:\n", bmname(bitmap));
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printk(KERN_DEBUG " magic: %08x\n", le32_to_cpu(sb->magic));
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printk(KERN_DEBUG " version: %d\n", le32_to_cpu(sb->version));
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printk(KERN_DEBUG " uuid: %08x.%08x.%08x.%08x\n",
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*(__u32 *)(sb->uuid+0),
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*(__u32 *)(sb->uuid+4),
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*(__u32 *)(sb->uuid+8),
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*(__u32 *)(sb->uuid+12));
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printk(KERN_DEBUG " events: %llu\n",
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(unsigned long long) le64_to_cpu(sb->events));
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printk(KERN_DEBUG "events cleared: %llu\n",
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(unsigned long long) le64_to_cpu(sb->events_cleared));
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printk(KERN_DEBUG " state: %08x\n", le32_to_cpu(sb->state));
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printk(KERN_DEBUG " chunksize: %d B\n", le32_to_cpu(sb->chunksize));
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printk(KERN_DEBUG " daemon sleep: %ds\n", le32_to_cpu(sb->daemon_sleep));
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printk(KERN_DEBUG " sync size: %llu KB\n",
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(unsigned long long)le64_to_cpu(sb->sync_size)/2);
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printk(KERN_DEBUG "max write behind: %d\n", le32_to_cpu(sb->write_behind));
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kunmap(bitmap->sb_page);
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}
|
|
|
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/* read the superblock from the bitmap file and initialize some bitmap fields */
|
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static int bitmap_read_sb(struct bitmap *bitmap)
|
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{
|
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char *reason = NULL;
|
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bitmap_super_t *sb;
|
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unsigned long chunksize, daemon_sleep, write_behind;
|
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unsigned long bytes_read;
|
|
unsigned long long events;
|
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int err = -EINVAL;
|
|
|
|
/* page 0 is the superblock, read it... */
|
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if (bitmap->file)
|
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bitmap->sb_page = read_page(bitmap->file, 0, &bytes_read);
|
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else {
|
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bitmap->sb_page = read_sb_page(bitmap->mddev, bitmap->offset, 0);
|
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bytes_read = PAGE_SIZE;
|
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}
|
|
if (IS_ERR(bitmap->sb_page)) {
|
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err = PTR_ERR(bitmap->sb_page);
|
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bitmap->sb_page = NULL;
|
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return err;
|
|
}
|
|
|
|
sb = (bitmap_super_t *)kmap(bitmap->sb_page);
|
|
|
|
if (bytes_read < sizeof(*sb)) { /* short read */
|
|
printk(KERN_INFO "%s: bitmap file superblock truncated\n",
|
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bmname(bitmap));
|
|
err = -ENOSPC;
|
|
goto out;
|
|
}
|
|
|
|
chunksize = le32_to_cpu(sb->chunksize);
|
|
daemon_sleep = le32_to_cpu(sb->daemon_sleep);
|
|
write_behind = le32_to_cpu(sb->write_behind);
|
|
|
|
/* verify that the bitmap-specific fields are valid */
|
|
if (sb->magic != cpu_to_le32(BITMAP_MAGIC))
|
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reason = "bad magic";
|
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else if (sb->version != cpu_to_le32(BITMAP_MAJOR))
|
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reason = "unrecognized superblock version";
|
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else if (chunksize < 512 || chunksize > (1024 * 1024 * 4))
|
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reason = "bitmap chunksize out of range (512B - 4MB)";
|
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else if ((1 << ffz(~chunksize)) != chunksize)
|
|
reason = "bitmap chunksize not a power of 2";
|
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else if (daemon_sleep < 1 || daemon_sleep > 15)
|
|
reason = "daemon sleep period out of range (1-15s)";
|
|
else if (write_behind > COUNTER_MAX)
|
|
reason = "write-behind limit out of range (0 - 16383)";
|
|
if (reason) {
|
|
printk(KERN_INFO "%s: invalid bitmap file superblock: %s\n",
|
|
bmname(bitmap), reason);
|
|
goto out;
|
|
}
|
|
|
|
/* keep the array size field of the bitmap superblock up to date */
|
|
sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
|
|
|
|
if (!bitmap->mddev->persistent)
|
|
goto success;
|
|
|
|
/*
|
|
* if we have a persistent array superblock, compare the
|
|
* bitmap's UUID and event counter to the mddev's
|
|
*/
|
|
if (memcmp(sb->uuid, bitmap->mddev->uuid, 16)) {
|
|
printk(KERN_INFO "%s: bitmap superblock UUID mismatch\n",
|
|
bmname(bitmap));
|
|
goto out;
|
|
}
|
|
events = le64_to_cpu(sb->events);
|
|
if (events < bitmap->mddev->events) {
|
|
printk(KERN_INFO "%s: bitmap file is out of date (%llu < %llu) "
|
|
"-- forcing full recovery\n", bmname(bitmap), events,
|
|
(unsigned long long) bitmap->mddev->events);
|
|
sb->state |= BITMAP_STALE;
|
|
}
|
|
success:
|
|
/* assign fields using values from superblock */
|
|
bitmap->chunksize = chunksize;
|
|
bitmap->daemon_sleep = daemon_sleep;
|
|
bitmap->daemon_lastrun = jiffies;
|
|
bitmap->max_write_behind = write_behind;
|
|
bitmap->flags |= sb->state;
|
|
bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
|
|
if (sb->state & BITMAP_STALE)
|
|
bitmap->events_cleared = bitmap->mddev->events;
|
|
err = 0;
|
|
out:
|
|
kunmap(bitmap->sb_page);
|
|
if (err)
|
|
bitmap_print_sb(bitmap);
|
|
return err;
|
|
}
|
|
|
|
enum bitmap_mask_op {
|
|
MASK_SET,
|
|
MASK_UNSET
|
|
};
|
|
|
|
/* record the state of the bitmap in the superblock */
|
|
static void bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
|
|
enum bitmap_mask_op op)
|
|
{
|
|
bitmap_super_t *sb;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
if (!bitmap || !bitmap->sb_page) { /* can't set the state */
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
return;
|
|
}
|
|
page_cache_get(bitmap->sb_page);
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
sb = (bitmap_super_t *)kmap(bitmap->sb_page);
|
|
switch (op) {
|
|
case MASK_SET: sb->state |= bits;
|
|
break;
|
|
case MASK_UNSET: sb->state &= ~bits;
|
|
break;
|
|
default: BUG();
|
|
}
|
|
kunmap(bitmap->sb_page);
|
|
page_cache_release(bitmap->sb_page);
|
|
}
|
|
|
|
/*
|
|
* general bitmap file operations
|
|
*/
|
|
|
|
/* calculate the index of the page that contains this bit */
|
|
static inline unsigned long file_page_index(unsigned long chunk)
|
|
{
|
|
return CHUNK_BIT_OFFSET(chunk) >> PAGE_BIT_SHIFT;
|
|
}
|
|
|
|
/* calculate the (bit) offset of this bit within a page */
|
|
static inline unsigned long file_page_offset(unsigned long chunk)
|
|
{
|
|
return CHUNK_BIT_OFFSET(chunk) & (PAGE_BITS - 1);
|
|
}
|
|
|
|
/*
|
|
* return a pointer to the page in the filemap that contains the given bit
|
|
*
|
|
* this lookup is complicated by the fact that the bitmap sb might be exactly
|
|
* 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page
|
|
* 0 or page 1
|
|
*/
|
|
static inline struct page *filemap_get_page(struct bitmap *bitmap,
|
|
unsigned long chunk)
|
|
{
|
|
return bitmap->filemap[file_page_index(chunk) - file_page_index(0)];
|
|
}
|
|
|
|
|
|
static void bitmap_file_unmap(struct bitmap *bitmap)
|
|
{
|
|
struct page **map, *sb_page;
|
|
unsigned long *attr;
|
|
int pages;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
map = bitmap->filemap;
|
|
bitmap->filemap = NULL;
|
|
attr = bitmap->filemap_attr;
|
|
bitmap->filemap_attr = NULL;
|
|
pages = bitmap->file_pages;
|
|
bitmap->file_pages = 0;
|
|
sb_page = bitmap->sb_page;
|
|
bitmap->sb_page = NULL;
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
|
|
while (pages--)
|
|
if (map[pages]->index != 0) /* 0 is sb_page, release it below */
|
|
page_cache_release(map[pages]);
|
|
kfree(map);
|
|
kfree(attr);
|
|
|
|
if (sb_page)
|
|
page_cache_release(sb_page);
|
|
}
|
|
|
|
static void bitmap_stop_daemons(struct bitmap *bitmap);
|
|
|
|
/* dequeue the next item in a page list -- don't call from irq context */
|
|
static struct page_list *dequeue_page(struct bitmap *bitmap)
|
|
{
|
|
struct page_list *item = NULL;
|
|
struct list_head *head = &bitmap->complete_pages;
|
|
|
|
spin_lock(&bitmap->write_lock);
|
|
if (list_empty(head))
|
|
goto out;
|
|
item = list_entry(head->prev, struct page_list, list);
|
|
list_del(head->prev);
|
|
out:
|
|
spin_unlock(&bitmap->write_lock);
|
|
return item;
|
|
}
|
|
|
|
static void drain_write_queues(struct bitmap *bitmap)
|
|
{
|
|
struct page_list *item;
|
|
|
|
while ((item = dequeue_page(bitmap))) {
|
|
/* don't bother to wait */
|
|
page_cache_release(item->page);
|
|
mempool_free(item, bitmap->write_pool);
|
|
}
|
|
|
|
wake_up(&bitmap->write_wait);
|
|
}
|
|
|
|
static void bitmap_file_put(struct bitmap *bitmap)
|
|
{
|
|
struct file *file;
|
|
struct inode *inode;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
file = bitmap->file;
|
|
bitmap->file = NULL;
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
|
|
bitmap_stop_daemons(bitmap);
|
|
|
|
drain_write_queues(bitmap);
|
|
|
|
bitmap_file_unmap(bitmap);
|
|
|
|
if (file) {
|
|
inode = file->f_mapping->host;
|
|
spin_lock(&inode->i_lock);
|
|
atomic_set(&inode->i_writecount, 1); /* allow writes again */
|
|
spin_unlock(&inode->i_lock);
|
|
fput(file);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* bitmap_file_kick - if an error occurs while manipulating the bitmap file
|
|
* then it is no longer reliable, so we stop using it and we mark the file
|
|
* as failed in the superblock
|
|
*/
|
|
static void bitmap_file_kick(struct bitmap *bitmap)
|
|
{
|
|
char *path, *ptr = NULL;
|
|
|
|
bitmap_mask_state(bitmap, BITMAP_STALE, MASK_SET);
|
|
bitmap_update_sb(bitmap);
|
|
|
|
if (bitmap->file) {
|
|
path = kmalloc(PAGE_SIZE, GFP_KERNEL);
|
|
if (path)
|
|
ptr = file_path(bitmap->file, path, PAGE_SIZE);
|
|
|
|
printk(KERN_ALERT "%s: kicking failed bitmap file %s from array!\n",
|
|
bmname(bitmap), ptr ? ptr : "");
|
|
|
|
kfree(path);
|
|
}
|
|
|
|
bitmap_file_put(bitmap);
|
|
|
|
return;
|
|
}
|
|
|
|
enum bitmap_page_attr {
|
|
BITMAP_PAGE_DIRTY = 1, // there are set bits that need to be synced
|
|
BITMAP_PAGE_CLEAN = 2, // there are bits that might need to be cleared
|
|
BITMAP_PAGE_NEEDWRITE=4, // there are cleared bits that need to be synced
|
|
};
|
|
|
|
static inline void set_page_attr(struct bitmap *bitmap, struct page *page,
|
|
enum bitmap_page_attr attr)
|
|
{
|
|
bitmap->filemap_attr[page->index] |= attr;
|
|
}
|
|
|
|
static inline void clear_page_attr(struct bitmap *bitmap, struct page *page,
|
|
enum bitmap_page_attr attr)
|
|
{
|
|
bitmap->filemap_attr[page->index] &= ~attr;
|
|
}
|
|
|
|
static inline unsigned long get_page_attr(struct bitmap *bitmap, struct page *page)
|
|
{
|
|
return bitmap->filemap_attr[page->index];
|
|
}
|
|
|
|
/*
|
|
* bitmap_file_set_bit -- called before performing a write to the md device
|
|
* to set (and eventually sync) a particular bit in the bitmap file
|
|
*
|
|
* we set the bit immediately, then we record the page number so that
|
|
* when an unplug occurs, we can flush the dirty pages out to disk
|
|
*/
|
|
static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
|
|
{
|
|
unsigned long bit;
|
|
struct page *page;
|
|
void *kaddr;
|
|
unsigned long chunk = block >> CHUNK_BLOCK_SHIFT(bitmap);
|
|
|
|
if (!bitmap->filemap) {
|
|
return;
|
|
}
|
|
|
|
page = filemap_get_page(bitmap, chunk);
|
|
bit = file_page_offset(chunk);
|
|
|
|
|
|
/* make sure the page stays cached until it gets written out */
|
|
if (! (get_page_attr(bitmap, page) & BITMAP_PAGE_DIRTY))
|
|
page_cache_get(page);
|
|
|
|
/* set the bit */
|
|
kaddr = kmap_atomic(page, KM_USER0);
|
|
set_bit(bit, kaddr);
|
|
kunmap_atomic(kaddr, KM_USER0);
|
|
PRINTK("set file bit %lu page %lu\n", bit, page->index);
|
|
|
|
/* record page number so it gets flushed to disk when unplug occurs */
|
|
set_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
|
|
|
|
}
|
|
|
|
/* this gets called when the md device is ready to unplug its underlying
|
|
* (slave) device queues -- before we let any writes go down, we need to
|
|
* sync the dirty pages of the bitmap file to disk */
|
|
int bitmap_unplug(struct bitmap *bitmap)
|
|
{
|
|
unsigned long i, attr, flags;
|
|
struct page *page;
|
|
int wait = 0;
|
|
int err;
|
|
|
|
if (!bitmap)
|
|
return 0;
|
|
|
|
/* look at each page to see if there are any set bits that need to be
|
|
* flushed out to disk */
|
|
for (i = 0; i < bitmap->file_pages; i++) {
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
if (!bitmap->filemap) {
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
return 0;
|
|
}
|
|
page = bitmap->filemap[i];
|
|
attr = get_page_attr(bitmap, page);
|
|
clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
|
|
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
|
|
if ((attr & BITMAP_PAGE_DIRTY))
|
|
wait = 1;
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
|
|
if (attr & (BITMAP_PAGE_DIRTY | BITMAP_PAGE_NEEDWRITE)) {
|
|
err = write_page(bitmap, page, 0);
|
|
if (err == -EAGAIN) {
|
|
if (attr & BITMAP_PAGE_DIRTY)
|
|
err = write_page(bitmap, page, 1);
|
|
else
|
|
err = 0;
|
|
}
|
|
if (err)
|
|
return 1;
|
|
}
|
|
}
|
|
if (wait) { /* if any writes were performed, we need to wait on them */
|
|
if (bitmap->file) {
|
|
spin_lock_irq(&bitmap->write_lock);
|
|
wait_event_lock_irq(bitmap->write_wait,
|
|
list_empty(&bitmap->complete_pages), bitmap->write_lock,
|
|
wake_up_process(bitmap->writeback_daemon->tsk));
|
|
spin_unlock_irq(&bitmap->write_lock);
|
|
} else
|
|
wait_event(bitmap->mddev->sb_wait,
|
|
atomic_read(&bitmap->mddev->pending_writes)==0);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
|
|
/* * bitmap_init_from_disk -- called at bitmap_create time to initialize
|
|
* the in-memory bitmap from the on-disk bitmap -- also, sets up the
|
|
* memory mapping of the bitmap file
|
|
* Special cases:
|
|
* if there's no bitmap file, or if the bitmap file had been
|
|
* previously kicked from the array, we mark all the bits as
|
|
* 1's in order to cause a full resync.
|
|
*
|
|
* We ignore all bits for sectors that end earlier than 'start'.
|
|
* This is used when reading an out-of-date bitmap...
|
|
*/
|
|
static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
|
|
{
|
|
unsigned long i, chunks, index, oldindex, bit;
|
|
struct page *page = NULL, *oldpage = NULL;
|
|
unsigned long num_pages, bit_cnt = 0;
|
|
struct file *file;
|
|
unsigned long bytes, offset, dummy;
|
|
int outofdate;
|
|
int ret = -ENOSPC;
|
|
|
|
chunks = bitmap->chunks;
|
|
file = bitmap->file;
|
|
|
|
BUG_ON(!file && !bitmap->offset);
|
|
|
|
#ifdef INJECT_FAULTS_3
|
|
outofdate = 1;
|
|
#else
|
|
outofdate = bitmap->flags & BITMAP_STALE;
|
|
#endif
|
|
if (outofdate)
|
|
printk(KERN_INFO "%s: bitmap file is out of date, doing full "
|
|
"recovery\n", bmname(bitmap));
|
|
|
|
bytes = (chunks + 7) / 8;
|
|
|
|
num_pages = (bytes + sizeof(bitmap_super_t) + PAGE_SIZE - 1) / PAGE_SIZE;
|
|
|
|
if (file && i_size_read(file->f_mapping->host) < bytes + sizeof(bitmap_super_t)) {
|
|
printk(KERN_INFO "%s: bitmap file too short %lu < %lu\n",
|
|
bmname(bitmap),
|
|
(unsigned long) i_size_read(file->f_mapping->host),
|
|
bytes + sizeof(bitmap_super_t));
|
|
goto out;
|
|
}
|
|
|
|
ret = -ENOMEM;
|
|
|
|
bitmap->filemap = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
|
|
if (!bitmap->filemap)
|
|
goto out;
|
|
|
|
bitmap->filemap_attr = kmalloc(sizeof(long) * num_pages, GFP_KERNEL);
|
|
if (!bitmap->filemap_attr)
|
|
goto out;
|
|
|
|
memset(bitmap->filemap_attr, 0, sizeof(long) * num_pages);
|
|
|
|
oldindex = ~0L;
|
|
|
|
for (i = 0; i < chunks; i++) {
|
|
index = file_page_index(i);
|
|
bit = file_page_offset(i);
|
|
if (index != oldindex) { /* this is a new page, read it in */
|
|
/* unmap the old page, we're done with it */
|
|
if (oldpage != NULL)
|
|
kunmap(oldpage);
|
|
if (index == 0) {
|
|
/*
|
|
* if we're here then the superblock page
|
|
* contains some bits (PAGE_SIZE != sizeof sb)
|
|
* we've already read it in, so just use it
|
|
*/
|
|
page = bitmap->sb_page;
|
|
offset = sizeof(bitmap_super_t);
|
|
} else if (file) {
|
|
page = read_page(file, index, &dummy);
|
|
offset = 0;
|
|
} else {
|
|
page = read_sb_page(bitmap->mddev, bitmap->offset, index);
|
|
offset = 0;
|
|
}
|
|
if (IS_ERR(page)) { /* read error */
|
|
ret = PTR_ERR(page);
|
|
goto out;
|
|
}
|
|
|
|
oldindex = index;
|
|
oldpage = page;
|
|
kmap(page);
|
|
|
|
if (outofdate) {
|
|
/*
|
|
* if bitmap is out of date, dirty the
|
|
* whole page and write it out
|
|
*/
|
|
memset(page_address(page) + offset, 0xff,
|
|
PAGE_SIZE - offset);
|
|
ret = write_page(bitmap, page, 1);
|
|
if (ret) {
|
|
kunmap(page);
|
|
/* release, page not in filemap yet */
|
|
page_cache_release(page);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
bitmap->filemap[bitmap->file_pages++] = page;
|
|
}
|
|
if (test_bit(bit, page_address(page))) {
|
|
/* if the disk bit is set, set the memory bit */
|
|
bitmap_set_memory_bits(bitmap, i << CHUNK_BLOCK_SHIFT(bitmap),
|
|
((i+1) << (CHUNK_BLOCK_SHIFT(bitmap)) >= start)
|
|
);
|
|
bit_cnt++;
|
|
set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
|
|
}
|
|
}
|
|
|
|
/* everything went OK */
|
|
ret = 0;
|
|
bitmap_mask_state(bitmap, BITMAP_STALE, MASK_UNSET);
|
|
|
|
if (page) /* unmap the last page */
|
|
kunmap(page);
|
|
|
|
if (bit_cnt) { /* Kick recovery if any bits were set */
|
|
set_bit(MD_RECOVERY_NEEDED, &bitmap->mddev->recovery);
|
|
md_wakeup_thread(bitmap->mddev->thread);
|
|
}
|
|
|
|
out:
|
|
printk(KERN_INFO "%s: bitmap initialized from disk: "
|
|
"read %lu/%lu pages, set %lu bits, status: %d\n",
|
|
bmname(bitmap), bitmap->file_pages, num_pages, bit_cnt, ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void bitmap_write_all(struct bitmap *bitmap)
|
|
{
|
|
/* We don't actually write all bitmap blocks here,
|
|
* just flag them as needing to be written
|
|
*/
|
|
|
|
unsigned long chunks = bitmap->chunks;
|
|
unsigned long bytes = (chunks+7)/8 + sizeof(bitmap_super_t);
|
|
unsigned long num_pages = (bytes + PAGE_SIZE-1) / PAGE_SIZE;
|
|
while (num_pages--)
|
|
bitmap->filemap_attr[num_pages] |= BITMAP_PAGE_NEEDWRITE;
|
|
}
|
|
|
|
|
|
static void bitmap_count_page(struct bitmap *bitmap, sector_t offset, int inc)
|
|
{
|
|
sector_t chunk = offset >> CHUNK_BLOCK_SHIFT(bitmap);
|
|
unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
|
|
bitmap->bp[page].count += inc;
|
|
/*
|
|
if (page == 0) printk("count page 0, offset %llu: %d gives %d\n",
|
|
(unsigned long long)offset, inc, bitmap->bp[page].count);
|
|
*/
|
|
bitmap_checkfree(bitmap, page);
|
|
}
|
|
static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
|
|
sector_t offset, int *blocks,
|
|
int create);
|
|
|
|
/*
|
|
* bitmap daemon -- periodically wakes up to clean bits and flush pages
|
|
* out to disk
|
|
*/
|
|
|
|
int bitmap_daemon_work(struct bitmap *bitmap)
|
|
{
|
|
unsigned long j;
|
|
unsigned long flags;
|
|
struct page *page = NULL, *lastpage = NULL;
|
|
int err = 0;
|
|
int blocks;
|
|
int attr;
|
|
|
|
if (bitmap == NULL)
|
|
return 0;
|
|
if (time_before(jiffies, bitmap->daemon_lastrun + bitmap->daemon_sleep*HZ))
|
|
return 0;
|
|
bitmap->daemon_lastrun = jiffies;
|
|
|
|
for (j = 0; j < bitmap->chunks; j++) {
|
|
bitmap_counter_t *bmc;
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
if (!bitmap->filemap) {
|
|
/* error or shutdown */
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
break;
|
|
}
|
|
|
|
page = filemap_get_page(bitmap, j);
|
|
|
|
if (page != lastpage) {
|
|
/* skip this page unless it's marked as needing cleaning */
|
|
if (!((attr=get_page_attr(bitmap, page)) & BITMAP_PAGE_CLEAN)) {
|
|
if (attr & BITMAP_PAGE_NEEDWRITE) {
|
|
page_cache_get(page);
|
|
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
|
|
}
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
if (attr & BITMAP_PAGE_NEEDWRITE) {
|
|
switch (write_page(bitmap, page, 0)) {
|
|
case -EAGAIN:
|
|
set_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
|
|
break;
|
|
case 0:
|
|
break;
|
|
default:
|
|
bitmap_file_kick(bitmap);
|
|
}
|
|
page_cache_release(page);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
/* grab the new page, sync and release the old */
|
|
page_cache_get(page);
|
|
if (lastpage != NULL) {
|
|
if (get_page_attr(bitmap, lastpage) & BITMAP_PAGE_NEEDWRITE) {
|
|
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
err = write_page(bitmap, lastpage, 0);
|
|
if (err == -EAGAIN) {
|
|
err = 0;
|
|
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
|
|
}
|
|
} else {
|
|
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
}
|
|
kunmap(lastpage);
|
|
page_cache_release(lastpage);
|
|
if (err)
|
|
bitmap_file_kick(bitmap);
|
|
} else
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
lastpage = page;
|
|
kmap(page);
|
|
/*
|
|
printk("bitmap clean at page %lu\n", j);
|
|
*/
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
clear_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
|
|
}
|
|
bmc = bitmap_get_counter(bitmap, j << CHUNK_BLOCK_SHIFT(bitmap),
|
|
&blocks, 0);
|
|
if (bmc) {
|
|
/*
|
|
if (j < 100) printk("bitmap: j=%lu, *bmc = 0x%x\n", j, *bmc);
|
|
*/
|
|
if (*bmc == 2) {
|
|
*bmc=1; /* maybe clear the bit next time */
|
|
set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
|
|
} else if (*bmc == 1) {
|
|
/* we can clear the bit */
|
|
*bmc = 0;
|
|
bitmap_count_page(bitmap, j << CHUNK_BLOCK_SHIFT(bitmap),
|
|
-1);
|
|
|
|
/* clear the bit */
|
|
clear_bit(file_page_offset(j), page_address(page));
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
}
|
|
|
|
/* now sync the final page */
|
|
if (lastpage != NULL) {
|
|
kunmap(lastpage);
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
if (get_page_attr(bitmap, lastpage) &BITMAP_PAGE_NEEDWRITE) {
|
|
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
err = write_page(bitmap, lastpage, 0);
|
|
if (err == -EAGAIN) {
|
|
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
|
|
err = 0;
|
|
}
|
|
} else {
|
|
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
}
|
|
|
|
page_cache_release(lastpage);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static void daemon_exit(struct bitmap *bitmap, mdk_thread_t **daemon)
|
|
{
|
|
mdk_thread_t *dmn;
|
|
unsigned long flags;
|
|
|
|
/* if no one is waiting on us, we'll free the md thread struct
|
|
* and exit, otherwise we let the waiter clean things up */
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
if ((dmn = *daemon)) { /* no one is waiting, cleanup and exit */
|
|
*daemon = NULL;
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
kfree(dmn);
|
|
complete_and_exit(NULL, 0); /* do_exit not exported */
|
|
}
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
}
|
|
|
|
static void bitmap_writeback_daemon(mddev_t *mddev)
|
|
{
|
|
struct bitmap *bitmap = mddev->bitmap;
|
|
struct page *page;
|
|
struct page_list *item;
|
|
int err = 0;
|
|
|
|
if (signal_pending(current)) {
|
|
printk(KERN_INFO
|
|
"%s: bitmap writeback daemon got signal, exiting...\n",
|
|
bmname(bitmap));
|
|
err = -EINTR;
|
|
goto out;
|
|
}
|
|
if (bitmap == NULL)
|
|
/* about to be stopped. */
|
|
return;
|
|
|
|
PRINTK("%s: bitmap writeback daemon woke up...\n", bmname(bitmap));
|
|
/* wait on bitmap page writebacks */
|
|
while ((item = dequeue_page(bitmap))) {
|
|
page = item->page;
|
|
mempool_free(item, bitmap->write_pool);
|
|
PRINTK("wait on page writeback: %p\n", page);
|
|
wait_on_page_writeback(page);
|
|
PRINTK("finished page writeback: %p\n", page);
|
|
|
|
err = PageError(page);
|
|
page_cache_release(page);
|
|
if (err) {
|
|
printk(KERN_WARNING "%s: bitmap file writeback "
|
|
"failed (page %lu): %d\n",
|
|
bmname(bitmap), page->index, err);
|
|
bitmap_file_kick(bitmap);
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
wake_up(&bitmap->write_wait);
|
|
if (err) {
|
|
printk(KERN_INFO "%s: bitmap writeback daemon exiting (%d)\n",
|
|
bmname(bitmap), err);
|
|
daemon_exit(bitmap, &bitmap->writeback_daemon);
|
|
}
|
|
}
|
|
|
|
static int bitmap_start_daemon(struct bitmap *bitmap, mdk_thread_t **ptr,
|
|
void (*func)(mddev_t *), char *name)
|
|
{
|
|
mdk_thread_t *daemon;
|
|
unsigned long flags;
|
|
char namebuf[32];
|
|
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
*ptr = NULL;
|
|
|
|
if (!bitmap->file) /* no need for daemon if there's no backing file */
|
|
goto out_unlock;
|
|
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
|
|
#ifdef INJECT_FATAL_FAULT_2
|
|
daemon = NULL;
|
|
#else
|
|
sprintf(namebuf, "%%s_%s", name);
|
|
daemon = md_register_thread(func, bitmap->mddev, namebuf);
|
|
#endif
|
|
if (!daemon) {
|
|
printk(KERN_ERR "%s: failed to start bitmap daemon\n",
|
|
bmname(bitmap));
|
|
return -ECHILD;
|
|
}
|
|
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
*ptr = daemon;
|
|
|
|
md_wakeup_thread(daemon); /* start it running */
|
|
|
|
PRINTK("%s: %s daemon (pid %d) started...\n",
|
|
bmname(bitmap), name, daemon->tsk->pid);
|
|
out_unlock:
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
return 0;
|
|
}
|
|
|
|
static int bitmap_start_daemons(struct bitmap *bitmap)
|
|
{
|
|
int err = bitmap_start_daemon(bitmap, &bitmap->writeback_daemon,
|
|
bitmap_writeback_daemon, "bitmap_wb");
|
|
return err;
|
|
}
|
|
|
|
static void bitmap_stop_daemon(struct bitmap *bitmap, mdk_thread_t **ptr)
|
|
{
|
|
mdk_thread_t *daemon;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
daemon = *ptr;
|
|
*ptr = NULL;
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
if (daemon)
|
|
md_unregister_thread(daemon); /* destroy the thread */
|
|
}
|
|
|
|
static void bitmap_stop_daemons(struct bitmap *bitmap)
|
|
{
|
|
/* the daemons can't stop themselves... they'll just exit instead... */
|
|
if (bitmap->writeback_daemon &&
|
|
current->pid != bitmap->writeback_daemon->tsk->pid)
|
|
bitmap_stop_daemon(bitmap, &bitmap->writeback_daemon);
|
|
}
|
|
|
|
static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
|
|
sector_t offset, int *blocks,
|
|
int create)
|
|
{
|
|
/* If 'create', we might release the lock and reclaim it.
|
|
* The lock must have been taken with interrupts enabled.
|
|
* If !create, we don't release the lock.
|
|
*/
|
|
sector_t chunk = offset >> CHUNK_BLOCK_SHIFT(bitmap);
|
|
unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
|
|
unsigned long pageoff = (chunk & PAGE_COUNTER_MASK) << COUNTER_BYTE_SHIFT;
|
|
sector_t csize;
|
|
|
|
if (bitmap_checkpage(bitmap, page, create) < 0) {
|
|
csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap));
|
|
*blocks = csize - (offset & (csize- 1));
|
|
return NULL;
|
|
}
|
|
/* now locked ... */
|
|
|
|
if (bitmap->bp[page].hijacked) { /* hijacked pointer */
|
|
/* should we use the first or second counter field
|
|
* of the hijacked pointer? */
|
|
int hi = (pageoff > PAGE_COUNTER_MASK);
|
|
csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap) +
|
|
PAGE_COUNTER_SHIFT - 1);
|
|
*blocks = csize - (offset & (csize- 1));
|
|
return &((bitmap_counter_t *)
|
|
&bitmap->bp[page].map)[hi];
|
|
} else { /* page is allocated */
|
|
csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap));
|
|
*blocks = csize - (offset & (csize- 1));
|
|
return (bitmap_counter_t *)
|
|
&(bitmap->bp[page].map[pageoff]);
|
|
}
|
|
}
|
|
|
|
int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind)
|
|
{
|
|
if (!bitmap) return 0;
|
|
|
|
if (behind) {
|
|
atomic_inc(&bitmap->behind_writes);
|
|
PRINTK(KERN_DEBUG "inc write-behind count %d/%d\n",
|
|
atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
|
|
}
|
|
|
|
while (sectors) {
|
|
int blocks;
|
|
bitmap_counter_t *bmc;
|
|
|
|
spin_lock_irq(&bitmap->lock);
|
|
bmc = bitmap_get_counter(bitmap, offset, &blocks, 1);
|
|
if (!bmc) {
|
|
spin_unlock_irq(&bitmap->lock);
|
|
return 0;
|
|
}
|
|
|
|
switch(*bmc) {
|
|
case 0:
|
|
bitmap_file_set_bit(bitmap, offset);
|
|
bitmap_count_page(bitmap,offset, 1);
|
|
blk_plug_device(bitmap->mddev->queue);
|
|
/* fall through */
|
|
case 1:
|
|
*bmc = 2;
|
|
}
|
|
if ((*bmc & COUNTER_MAX) == COUNTER_MAX) BUG();
|
|
(*bmc)++;
|
|
|
|
spin_unlock_irq(&bitmap->lock);
|
|
|
|
offset += blocks;
|
|
if (sectors > blocks)
|
|
sectors -= blocks;
|
|
else sectors = 0;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
|
|
int success, int behind)
|
|
{
|
|
if (!bitmap) return;
|
|
if (behind) {
|
|
atomic_dec(&bitmap->behind_writes);
|
|
PRINTK(KERN_DEBUG "dec write-behind count %d/%d\n",
|
|
atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
|
|
}
|
|
|
|
while (sectors) {
|
|
int blocks;
|
|
unsigned long flags;
|
|
bitmap_counter_t *bmc;
|
|
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
bmc = bitmap_get_counter(bitmap, offset, &blocks, 0);
|
|
if (!bmc) {
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
return;
|
|
}
|
|
|
|
if (!success && ! (*bmc & NEEDED_MASK))
|
|
*bmc |= NEEDED_MASK;
|
|
|
|
(*bmc)--;
|
|
if (*bmc <= 2) {
|
|
set_page_attr(bitmap,
|
|
filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap)),
|
|
BITMAP_PAGE_CLEAN);
|
|
}
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
offset += blocks;
|
|
if (sectors > blocks)
|
|
sectors -= blocks;
|
|
else sectors = 0;
|
|
}
|
|
}
|
|
|
|
int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks,
|
|
int degraded)
|
|
{
|
|
bitmap_counter_t *bmc;
|
|
int rv;
|
|
if (bitmap == NULL) {/* FIXME or bitmap set as 'failed' */
|
|
*blocks = 1024;
|
|
return 1; /* always resync if no bitmap */
|
|
}
|
|
spin_lock_irq(&bitmap->lock);
|
|
bmc = bitmap_get_counter(bitmap, offset, blocks, 0);
|
|
rv = 0;
|
|
if (bmc) {
|
|
/* locked */
|
|
if (RESYNC(*bmc))
|
|
rv = 1;
|
|
else if (NEEDED(*bmc)) {
|
|
rv = 1;
|
|
if (!degraded) { /* don't set/clear bits if degraded */
|
|
*bmc |= RESYNC_MASK;
|
|
*bmc &= ~NEEDED_MASK;
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irq(&bitmap->lock);
|
|
return rv;
|
|
}
|
|
|
|
void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, int *blocks, int aborted)
|
|
{
|
|
bitmap_counter_t *bmc;
|
|
unsigned long flags;
|
|
/*
|
|
if (offset == 0) printk("bitmap_end_sync 0 (%d)\n", aborted);
|
|
*/ if (bitmap == NULL) {
|
|
*blocks = 1024;
|
|
return;
|
|
}
|
|
spin_lock_irqsave(&bitmap->lock, flags);
|
|
bmc = bitmap_get_counter(bitmap, offset, blocks, 0);
|
|
if (bmc == NULL)
|
|
goto unlock;
|
|
/* locked */
|
|
/*
|
|
if (offset == 0) printk("bitmap_end sync found 0x%x, blocks %d\n", *bmc, *blocks);
|
|
*/
|
|
if (RESYNC(*bmc)) {
|
|
*bmc &= ~RESYNC_MASK;
|
|
|
|
if (!NEEDED(*bmc) && aborted)
|
|
*bmc |= NEEDED_MASK;
|
|
else {
|
|
if (*bmc <= 2) {
|
|
set_page_attr(bitmap,
|
|
filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap)),
|
|
BITMAP_PAGE_CLEAN);
|
|
}
|
|
}
|
|
}
|
|
unlock:
|
|
spin_unlock_irqrestore(&bitmap->lock, flags);
|
|
}
|
|
|
|
void bitmap_close_sync(struct bitmap *bitmap)
|
|
{
|
|
/* Sync has finished, and any bitmap chunks that weren't synced
|
|
* properly have been aborted. It remains to us to clear the
|
|
* RESYNC bit wherever it is still on
|
|
*/
|
|
sector_t sector = 0;
|
|
int blocks;
|
|
if (!bitmap) return;
|
|
while (sector < bitmap->mddev->resync_max_sectors) {
|
|
bitmap_end_sync(bitmap, sector, &blocks, 0);
|
|
/*
|
|
if (sector < 500) printk("bitmap_close_sync: sec %llu blks %d\n",
|
|
(unsigned long long)sector, blocks);
|
|
*/ sector += blocks;
|
|
}
|
|
}
|
|
|
|
static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed)
|
|
{
|
|
/* For each chunk covered by any of these sectors, set the
|
|
* counter to 1 and set resync_needed. They should all
|
|
* be 0 at this point
|
|
*/
|
|
|
|
int secs;
|
|
bitmap_counter_t *bmc;
|
|
spin_lock_irq(&bitmap->lock);
|
|
bmc = bitmap_get_counter(bitmap, offset, &secs, 1);
|
|
if (!bmc) {
|
|
spin_unlock_irq(&bitmap->lock);
|
|
return;
|
|
}
|
|
if (! *bmc) {
|
|
struct page *page;
|
|
*bmc = 1 | (needed?NEEDED_MASK:0);
|
|
bitmap_count_page(bitmap, offset, 1);
|
|
page = filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap));
|
|
set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
|
|
}
|
|
spin_unlock_irq(&bitmap->lock);
|
|
|
|
}
|
|
|
|
/*
|
|
* flush out any pending updates
|
|
*/
|
|
void bitmap_flush(mddev_t *mddev)
|
|
{
|
|
struct bitmap *bitmap = mddev->bitmap;
|
|
int sleep;
|
|
|
|
if (!bitmap) /* there was no bitmap */
|
|
return;
|
|
|
|
/* run the daemon_work three time to ensure everything is flushed
|
|
* that can be
|
|
*/
|
|
sleep = bitmap->daemon_sleep;
|
|
bitmap->daemon_sleep = 0;
|
|
bitmap_daemon_work(bitmap);
|
|
bitmap_daemon_work(bitmap);
|
|
bitmap_daemon_work(bitmap);
|
|
bitmap->daemon_sleep = sleep;
|
|
bitmap_update_sb(bitmap);
|
|
}
|
|
|
|
/*
|
|
* free memory that was allocated
|
|
*/
|
|
static void bitmap_free(struct bitmap *bitmap)
|
|
{
|
|
unsigned long k, pages;
|
|
struct bitmap_page *bp;
|
|
|
|
if (!bitmap) /* there was no bitmap */
|
|
return;
|
|
|
|
/* release the bitmap file and kill the daemon */
|
|
bitmap_file_put(bitmap);
|
|
|
|
bp = bitmap->bp;
|
|
pages = bitmap->pages;
|
|
|
|
/* free all allocated memory */
|
|
|
|
mempool_destroy(bitmap->write_pool);
|
|
|
|
if (bp) /* deallocate the page memory */
|
|
for (k = 0; k < pages; k++)
|
|
if (bp[k].map && !bp[k].hijacked)
|
|
kfree(bp[k].map);
|
|
kfree(bp);
|
|
kfree(bitmap);
|
|
}
|
|
void bitmap_destroy(mddev_t *mddev)
|
|
{
|
|
struct bitmap *bitmap = mddev->bitmap;
|
|
|
|
if (!bitmap) /* there was no bitmap */
|
|
return;
|
|
|
|
mddev->bitmap = NULL; /* disconnect from the md device */
|
|
|
|
bitmap_free(bitmap);
|
|
}
|
|
|
|
/*
|
|
* initialize the bitmap structure
|
|
* if this returns an error, bitmap_destroy must be called to do clean up
|
|
*/
|
|
int bitmap_create(mddev_t *mddev)
|
|
{
|
|
struct bitmap *bitmap;
|
|
unsigned long blocks = mddev->resync_max_sectors;
|
|
unsigned long chunks;
|
|
unsigned long pages;
|
|
struct file *file = mddev->bitmap_file;
|
|
int err;
|
|
sector_t start;
|
|
|
|
BUG_ON(sizeof(bitmap_super_t) != 256);
|
|
|
|
if (!file && !mddev->bitmap_offset) /* bitmap disabled, nothing to do */
|
|
return 0;
|
|
|
|
BUG_ON(file && mddev->bitmap_offset);
|
|
|
|
bitmap = kmalloc(sizeof(*bitmap), GFP_KERNEL);
|
|
if (!bitmap)
|
|
return -ENOMEM;
|
|
|
|
memset(bitmap, 0, sizeof(*bitmap));
|
|
|
|
spin_lock_init(&bitmap->lock);
|
|
bitmap->mddev = mddev;
|
|
|
|
spin_lock_init(&bitmap->write_lock);
|
|
INIT_LIST_HEAD(&bitmap->complete_pages);
|
|
init_waitqueue_head(&bitmap->write_wait);
|
|
bitmap->write_pool = mempool_create(WRITE_POOL_SIZE, write_pool_alloc,
|
|
write_pool_free, NULL);
|
|
err = -ENOMEM;
|
|
if (!bitmap->write_pool)
|
|
goto error;
|
|
|
|
bitmap->file = file;
|
|
bitmap->offset = mddev->bitmap_offset;
|
|
if (file) get_file(file);
|
|
/* read superblock from bitmap file (this sets bitmap->chunksize) */
|
|
err = bitmap_read_sb(bitmap);
|
|
if (err)
|
|
goto error;
|
|
|
|
bitmap->chunkshift = find_first_bit(&bitmap->chunksize,
|
|
sizeof(bitmap->chunksize));
|
|
|
|
/* now that chunksize and chunkshift are set, we can use these macros */
|
|
chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) /
|
|
CHUNK_BLOCK_RATIO(bitmap);
|
|
pages = (chunks + PAGE_COUNTER_RATIO - 1) / PAGE_COUNTER_RATIO;
|
|
|
|
BUG_ON(!pages);
|
|
|
|
bitmap->chunks = chunks;
|
|
bitmap->pages = pages;
|
|
bitmap->missing_pages = pages;
|
|
bitmap->counter_bits = COUNTER_BITS;
|
|
|
|
bitmap->syncchunk = ~0UL;
|
|
|
|
#ifdef INJECT_FATAL_FAULT_1
|
|
bitmap->bp = NULL;
|
|
#else
|
|
bitmap->bp = kmalloc(pages * sizeof(*bitmap->bp), GFP_KERNEL);
|
|
#endif
|
|
err = -ENOMEM;
|
|
if (!bitmap->bp)
|
|
goto error;
|
|
memset(bitmap->bp, 0, pages * sizeof(*bitmap->bp));
|
|
|
|
bitmap->flags |= BITMAP_ACTIVE;
|
|
|
|
/* now that we have some pages available, initialize the in-memory
|
|
* bitmap from the on-disk bitmap */
|
|
start = 0;
|
|
if (mddev->degraded == 0
|
|
|| bitmap->events_cleared == mddev->events)
|
|
/* no need to keep dirty bits to optimise a re-add of a missing device */
|
|
start = mddev->recovery_cp;
|
|
err = bitmap_init_from_disk(bitmap, start);
|
|
|
|
if (err)
|
|
goto error;
|
|
|
|
printk(KERN_INFO "created bitmap (%lu pages) for device %s\n",
|
|
pages, bmname(bitmap));
|
|
|
|
mddev->bitmap = bitmap;
|
|
|
|
/* kick off the bitmap daemons */
|
|
err = bitmap_start_daemons(bitmap);
|
|
if (err)
|
|
return err;
|
|
return bitmap_update_sb(bitmap);
|
|
|
|
error:
|
|
bitmap_free(bitmap);
|
|
return err;
|
|
}
|
|
|
|
/* the bitmap API -- for raid personalities */
|
|
EXPORT_SYMBOL(bitmap_startwrite);
|
|
EXPORT_SYMBOL(bitmap_endwrite);
|
|
EXPORT_SYMBOL(bitmap_start_sync);
|
|
EXPORT_SYMBOL(bitmap_end_sync);
|
|
EXPORT_SYMBOL(bitmap_unplug);
|
|
EXPORT_SYMBOL(bitmap_close_sync);
|
|
EXPORT_SYMBOL(bitmap_daemon_work);
|