diff options
| author | Anton Altaparmakov <aia21@cam.ac.uk> | 2007-10-12 09:37:15 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-12 09:16:30 -0700 |
| commit | bfab36e81611e60573b84eb4e4b4c8d8545b2320 (patch) | |
| tree | acd151a4c85459dcd2f6575ceb385090ebaaf984 /fs/ntfs/aops.c | |
| parent | f26e51f67ae6a75ffc57b96cf5fe096f75e778cb (diff) | |
NTFS: Fix a mount time deadlock.
Big thanks go to Mathias Kolehmainen for reporting the bug, providing
debug output and testing the patches I sent him to get it working.
The fix was to stop calling ntfs_attr_set() at mount time as that causes
balance_dirty_pages_ratelimited() to be called which on systems with
little memory actually tries to go and balance the dirty pages which tries
to take the s_umount semaphore but because we are still in fill_super()
across which the VFS holds s_umount for writing this results in a
deadlock.
We now do the dirty work by hand by submitting individual buffers. This
has the annoying "feature" that mounting can take a few seconds if the
journal is large as we have clear it all. One day someone should improve
on this by deferring the journal clearing to a helper kernel thread so it
can be done in the background but I don't have time for this at the moment
and the current solution works fine so I am leaving it like this for now.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/ntfs/aops.c')
| -rw-r--r-- | fs/ntfs/aops.c | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c index 6e5c2534f4bc..cfdc7900d271 100644 --- a/fs/ntfs/aops.c +++ b/fs/ntfs/aops.c @@ -2,7 +2,7 @@ * aops.c - NTFS kernel address space operations and page cache handling. * Part of the Linux-NTFS project. * - * Copyright (c) 2001-2006 Anton Altaparmakov + * Copyright (c) 2001-2007 Anton Altaparmakov * Copyright (c) 2002 Richard Russon * * This program/include file is free software; you can redistribute it and/or @@ -396,7 +396,7 @@ static int ntfs_readpage(struct file *file, struct page *page) loff_t i_size; struct inode *vi; ntfs_inode *ni, *base_ni; - u8 *kaddr; + u8 *addr; ntfs_attr_search_ctx *ctx; MFT_RECORD *mrec; unsigned long flags; @@ -491,15 +491,15 @@ retry_readpage: /* Race with shrinking truncate. */ attr_len = i_size; } - kaddr = kmap_atomic(page, KM_USER0); + addr = kmap_atomic(page, KM_USER0); /* Copy the data to the page. */ - memcpy(kaddr, (u8*)ctx->attr + + memcpy(addr, (u8*)ctx->attr + le16_to_cpu(ctx->attr->data.resident.value_offset), attr_len); /* Zero the remainder of the page. */ - memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); + memset(addr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); flush_dcache_page(page); - kunmap_atomic(kaddr, KM_USER0); + kunmap_atomic(addr, KM_USER0); put_unm_err_out: ntfs_attr_put_search_ctx(ctx); unm_err_out: @@ -1344,7 +1344,7 @@ static int ntfs_writepage(struct page *page, struct writeback_control *wbc) loff_t i_size; struct inode *vi = page->mapping->host; ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi); - char *kaddr; + char *addr; ntfs_attr_search_ctx *ctx = NULL; MFT_RECORD *m = NULL; u32 attr_len; @@ -1484,14 +1484,14 @@ retry_writepage: /* Shrinking cannot fail. */ BUG_ON(err); } - kaddr = kmap_atomic(page, KM_USER0); + addr = kmap_atomic(page, KM_USER0); /* Copy the data from the page to the mft record. */ memcpy((u8*)ctx->attr + le16_to_cpu(ctx->attr->data.resident.value_offset), - kaddr, attr_len); + addr, attr_len); /* Zero out of bounds area in the page cache page. */ - memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); - kunmap_atomic(kaddr, KM_USER0); + memset(addr + attr_len, 0, PAGE_CACHE_SIZE - attr_len); + kunmap_atomic(addr, KM_USER0); flush_dcache_page(page); flush_dcache_mft_record_page(ctx->ntfs_ino); /* We are done with the page. */ |