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Diffstat (limited to 'fs/ntfs/aops.c')
-rw-r--r--fs/ntfs/aops.c295
1 files changed, 171 insertions, 124 deletions
diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c
index 3f43bfe6184e..b6cc8cf24626 100644
--- a/fs/ntfs/aops.c
+++ b/fs/ntfs/aops.c
@@ -27,6 +27,7 @@
#include <linux/swap.h>
#include <linux/buffer_head.h>
#include <linux/writeback.h>
+#include <linux/bit_spinlock.h>
#include "aops.h"
#include "attrib.h"
@@ -55,9 +56,8 @@
*/
static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
{
- static DEFINE_SPINLOCK(page_uptodate_lock);
unsigned long flags;
- struct buffer_head *tmp;
+ struct buffer_head *first, *tmp;
struct page *page;
ntfs_inode *ni;
int page_uptodate = 1;
@@ -89,11 +89,13 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
}
} else {
clear_buffer_uptodate(bh);
+ SetPageError(page);
ntfs_error(ni->vol->sb, "Buffer I/O error, logical block %llu.",
(unsigned long long)bh->b_blocknr);
- SetPageError(page);
}
- spin_lock_irqsave(&page_uptodate_lock, flags);
+ first = page_buffers(page);
+ local_irq_save(flags);
+ bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
clear_buffer_async_read(bh);
unlock_buffer(bh);
tmp = bh;
@@ -108,7 +110,8 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
}
tmp = tmp->b_this_page;
} while (tmp != bh);
- spin_unlock_irqrestore(&page_uptodate_lock, flags);
+ bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+ local_irq_restore(flags);
/*
* If none of the buffers had errors then we can set the page uptodate,
* but we first have to perform the post read mst fixups, if the
@@ -141,7 +144,8 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
unlock_page(page);
return;
still_busy:
- spin_unlock_irqrestore(&page_uptodate_lock, flags);
+ bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+ local_irq_restore(flags);
return;
}
@@ -185,13 +189,15 @@ static int ntfs_read_block(struct page *page)
blocksize_bits = VFS_I(ni)->i_blkbits;
blocksize = 1 << blocksize_bits;
- if (!page_has_buffers(page))
+ if (!page_has_buffers(page)) {
create_empty_buffers(page, blocksize, 0);
- bh = head = page_buffers(page);
- if (unlikely(!bh)) {
- unlock_page(page);
- return -ENOMEM;
+ if (unlikely(!page_has_buffers(page))) {
+ unlock_page(page);
+ return -ENOMEM;
+ }
}
+ bh = head = page_buffers(page);
+ BUG_ON(!bh);
iblock = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
read_lock_irqsave(&ni->size_lock, flags);
@@ -204,6 +210,7 @@ static int ntfs_read_block(struct page *page)
nr = i = 0;
do {
u8 *kaddr;
+ int err;
if (unlikely(buffer_uptodate(bh)))
continue;
@@ -211,6 +218,7 @@ static int ntfs_read_block(struct page *page)
arr[nr++] = bh;
continue;
}
+ err = 0;
bh->b_bdev = vol->sb->s_bdev;
/* Is the block within the allowed limits? */
if (iblock < lblock) {
@@ -252,7 +260,6 @@ lock_retry_remap:
goto handle_hole;
/* If first try and runlist unmapped, map and retry. */
if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
- int err;
is_retry = TRUE;
/*
* Attempt to map runlist, dropping lock for
@@ -263,20 +270,30 @@ lock_retry_remap:
if (likely(!err))
goto lock_retry_remap;
rl = NULL;
- lcn = err;
} else if (!rl)
up_read(&ni->runlist.lock);
+ /*
+ * If buffer is outside the runlist, treat it as a
+ * hole. This can happen due to concurrent truncate
+ * for example.
+ */
+ if (err == -ENOENT || lcn == LCN_ENOENT) {
+ err = 0;
+ goto handle_hole;
+ }
/* Hard error, zero out region. */
+ if (!err)
+ err = -EIO;
bh->b_blocknr = -1;
SetPageError(page);
ntfs_error(vol->sb, "Failed to read from inode 0x%lx, "
"attribute type 0x%x, vcn 0x%llx, "
"offset 0x%x because its location on "
"disk could not be determined%s "
- "(error code %lli).", ni->mft_no,
+ "(error code %i).", ni->mft_no,
ni->type, (unsigned long long)vcn,
vcn_ofs, is_retry ? " even after "
- "retrying" : "", (long long)lcn);
+ "retrying" : "", err);
}
/*
* Either iblock was outside lblock limits or
@@ -289,9 +306,10 @@ handle_hole:
handle_zblock:
kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr + i * blocksize, 0, blocksize);
- flush_dcache_page(page);
kunmap_atomic(kaddr, KM_USER0);
- set_buffer_uptodate(bh);
+ flush_dcache_page(page);
+ if (likely(!err))
+ set_buffer_uptodate(bh);
} while (i++, iblock++, (bh = bh->b_this_page) != head);
/* Release the lock if we took it. */
@@ -367,31 +385,38 @@ retry_readpage:
return 0;
}
ni = NTFS_I(page->mapping->host);
-
+ /*
+ * Only $DATA attributes can be encrypted and only unnamed $DATA
+ * attributes can be compressed. Index root can have the flags set but
+ * this means to create compressed/encrypted files, not that the
+ * attribute is compressed/encrypted.
+ */
+ if (ni->type != AT_INDEX_ROOT) {
+ /* If attribute is encrypted, deny access, just like NT4. */
+ if (NInoEncrypted(ni)) {
+ BUG_ON(ni->type != AT_DATA);
+ err = -EACCES;
+ goto err_out;
+ }
+ /* Compressed data streams are handled in compress.c. */
+ if (NInoNonResident(ni) && NInoCompressed(ni)) {
+ BUG_ON(ni->type != AT_DATA);
+ BUG_ON(ni->name_len);
+ return ntfs_read_compressed_block(page);
+ }
+ }
/* NInoNonResident() == NInoIndexAllocPresent() */
if (NInoNonResident(ni)) {
- /*
- * Only unnamed $DATA attributes can be compressed or
- * encrypted.
- */
- if (ni->type == AT_DATA && !ni->name_len) {
- /* If file is encrypted, deny access, just like NT4. */
- if (NInoEncrypted(ni)) {
- err = -EACCES;
- goto err_out;
- }
- /* Compressed data streams are handled in compress.c. */
- if (NInoCompressed(ni))
- return ntfs_read_compressed_block(page);
- }
- /* Normal data stream. */
+ /* Normal, non-resident data stream. */
return ntfs_read_block(page);
}
/*
* Attribute is resident, implying it is not compressed or encrypted.
* This also means the attribute is smaller than an mft record and
* hence smaller than a page, so can simply zero out any pages with
- * index above 0.
+ * index above 0. Note the attribute can actually be marked compressed
+ * but if it is resident the actual data is not compressed so we are
+ * ok to ignore the compressed flag here.
*/
if (unlikely(page->index > 0)) {
kaddr = kmap_atomic(page, KM_USER0);
@@ -511,19 +536,21 @@ static int ntfs_write_block(struct page *page, struct writeback_control *wbc)
BUG_ON(!PageUptodate(page));
create_empty_buffers(page, blocksize,
(1 << BH_Uptodate) | (1 << BH_Dirty));
+ if (unlikely(!page_has_buffers(page))) {
+ ntfs_warning(vol->sb, "Error allocating page "
+ "buffers. Redirtying page so we try "
+ "again later.");
+ /*
+ * Put the page back on mapping->dirty_pages, but leave
+ * its buffers' dirty state as-is.
+ */
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+ }
}
bh = head = page_buffers(page);
- if (unlikely(!bh)) {
- ntfs_warning(vol->sb, "Error allocating page buffers. "
- "Redirtying page so we try again later.");
- /*
- * Put the page back on mapping->dirty_pages, but leave its
- * buffer's dirty state as-is.
- */
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- return 0;
- }
+ BUG_ON(!bh);
/* NOTE: Different naming scheme to ntfs_read_block()! */
@@ -670,6 +697,27 @@ lock_retry_remap:
}
/* It is a hole, need to instantiate it. */
if (lcn == LCN_HOLE) {
+ u8 *kaddr;
+ unsigned long *bpos, *bend;
+
+ /* Check if the buffer is zero. */
+ kaddr = kmap_atomic(page, KM_USER0);
+ bpos = (unsigned long *)(kaddr + bh_offset(bh));
+ bend = (unsigned long *)((u8*)bpos + blocksize);
+ do {
+ if (unlikely(*bpos))
+ break;
+ } while (likely(++bpos < bend));
+ kunmap_atomic(kaddr, KM_USER0);
+ if (bpos == bend) {
+ /*
+ * Buffer is zero and sparse, no need to write
+ * it.
+ */
+ bh->b_blocknr = -1;
+ clear_buffer_dirty(bh);
+ continue;
+ }
// TODO: Instantiate the hole.
// clear_buffer_new(bh);
// unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
@@ -690,20 +738,37 @@ lock_retry_remap:
if (likely(!err))
goto lock_retry_remap;
rl = NULL;
- lcn = err;
} else if (!rl)
up_read(&ni->runlist.lock);
+ /*
+ * If buffer is outside the runlist, truncate has cut it out
+ * of the runlist. Just clean and clear the buffer and set it
+ * uptodate so it can get discarded by the VM.
+ */
+ if (err == -ENOENT || lcn == LCN_ENOENT) {
+ u8 *kaddr;
+
+ bh->b_blocknr = -1;
+ clear_buffer_dirty(bh);
+ kaddr = kmap_atomic(page, KM_USER0);
+ memset(kaddr + bh_offset(bh), 0, blocksize);
+ kunmap_atomic(kaddr, KM_USER0);
+ flush_dcache_page(page);
+ set_buffer_uptodate(bh);
+ err = 0;
+ continue;
+ }
/* Failed to map the buffer, even after retrying. */
+ if (!err)
+ err = -EIO;
bh->b_blocknr = -1;
ntfs_error(vol->sb, "Failed to write to inode 0x%lx, "
"attribute type 0x%x, vcn 0x%llx, offset 0x%x "
"because its location on disk could not be "
- "determined%s (error code %lli).", ni->mft_no,
+ "determined%s (error code %i).", ni->mft_no,
ni->type, (unsigned long long)vcn,
vcn_ofs, is_retry ? " even after "
- "retrying" : "", (long long)lcn);
- if (!err)
- err = -EIO;
+ "retrying" : "", err);
break;
} while (block++, (bh = bh->b_this_page) != head);
@@ -714,7 +779,7 @@ lock_retry_remap:
/* For the error case, need to reset bh to the beginning. */
bh = head;
- /* Just an optimization, so ->readpage() isn't called later. */
+ /* Just an optimization, so ->readpage() is not called later. */
if (unlikely(!PageUptodate(page))) {
int uptodate = 1;
do {
@@ -730,7 +795,6 @@ lock_retry_remap:
/* Setup all mapped, dirty buffers for async write i/o. */
do {
- get_bh(bh);
if (buffer_mapped(bh) && buffer_dirty(bh)) {
lock_buffer(bh);
if (test_clear_buffer_dirty(bh)) {
@@ -768,14 +832,8 @@ lock_retry_remap:
BUG_ON(PageWriteback(page));
set_page_writeback(page); /* Keeps try_to_free_buffers() away. */
- unlock_page(page);
- /*
- * Submit the prepared buffers for i/o. Note the page is unlocked,
- * and the async write i/o completion handler can end_page_writeback()
- * at any time after the *first* submit_bh(). So the buffers can then
- * disappear...
- */
+ /* Submit the prepared buffers for i/o. */
need_end_writeback = TRUE;
do {
struct buffer_head *next = bh->b_this_page;
@@ -783,9 +841,9 @@ lock_retry_remap:
submit_bh(WRITE, bh);
need_end_writeback = FALSE;
}
- put_bh(bh);
bh = next;
} while (bh != head);
+ unlock_page(page);
/* If no i/o was started, need to end_page_writeback(). */
if (unlikely(need_end_writeback))
@@ -860,7 +918,6 @@ static int ntfs_write_mst_block(struct page *page,
sync = (wbc->sync_mode == WB_SYNC_ALL);
/* Make sure we have mapped buffers. */
- BUG_ON(!page_has_buffers(page));
bh = head = page_buffers(page);
BUG_ON(!bh);
@@ -924,6 +981,7 @@ static int ntfs_write_mst_block(struct page *page,
LCN lcn;
unsigned int vcn_ofs;
+ bh->b_bdev = vol->sb->s_bdev;
/* Obtain the vcn and offset of the current block. */
vcn = (VCN)block << bh_size_bits;
vcn_ofs = vcn & vol->cluster_size_mask;
@@ -1279,38 +1337,42 @@ retry_writepage:
ntfs_debug("Write outside i_size - truncated?");
return 0;
}
+ /*
+ * Only $DATA attributes can be encrypted and only unnamed $DATA
+ * attributes can be compressed. Index root can have the flags set but
+ * this means to create compressed/encrypted files, not that the
+ * attribute is compressed/encrypted.
+ */
+ if (ni->type != AT_INDEX_ROOT) {
+ /* If file is encrypted, deny access, just like NT4. */
+ if (NInoEncrypted(ni)) {
+ unlock_page(page);
+ BUG_ON(ni->type != AT_DATA);
+ ntfs_debug("Denying write access to encrypted "
+ "file.");
+ return -EACCES;
+ }
+ /* Compressed data streams are handled in compress.c. */
+ if (NInoNonResident(ni) && NInoCompressed(ni)) {
+ BUG_ON(ni->type != AT_DATA);
+ BUG_ON(ni->name_len);
+ // TODO: Implement and replace this with
+ // return ntfs_write_compressed_block(page);
+ unlock_page(page);
+ ntfs_error(vi->i_sb, "Writing to compressed files is "
+ "not supported yet. Sorry.");
+ return -EOPNOTSUPP;
+ }
+ // TODO: Implement and remove this check.
+ if (NInoNonResident(ni) && NInoSparse(ni)) {
+ unlock_page(page);
+ ntfs_error(vi->i_sb, "Writing to sparse files is not "
+ "supported yet. Sorry.");
+ return -EOPNOTSUPP;
+ }
+ }
/* NInoNonResident() == NInoIndexAllocPresent() */
if (NInoNonResident(ni)) {
- /*
- * Only unnamed $DATA attributes can be compressed, encrypted,
- * and/or sparse.
- */
- if (ni->type == AT_DATA && !ni->name_len) {
- /* If file is encrypted, deny access, just like NT4. */
- if (NInoEncrypted(ni)) {
- unlock_page(page);
- ntfs_debug("Denying write access to encrypted "
- "file.");
- return -EACCES;
- }
- /* Compressed data streams are handled in compress.c. */
- if (NInoCompressed(ni)) {
- // TODO: Implement and replace this check with
- // return ntfs_write_compressed_block(page);
- unlock_page(page);
- ntfs_error(vi->i_sb, "Writing to compressed "
- "files is not supported yet. "
- "Sorry.");
- return -EOPNOTSUPP;
- }
- // TODO: Implement and remove this check.
- if (NInoSparse(ni)) {
- unlock_page(page);
- ntfs_error(vi->i_sb, "Writing to sparse files "
- "is not supported yet. Sorry.");
- return -EOPNOTSUPP;
- }
- }
/* We have to zero every time due to mmap-at-end-of-file. */
if (page->index >= (i_size >> PAGE_CACHE_SHIFT)) {
/* The page straddles i_size. */
@@ -1323,14 +1385,16 @@ retry_writepage:
/* Handle mst protected attributes. */
if (NInoMstProtected(ni))
return ntfs_write_mst_block(page, wbc);
- /* Normal data stream. */
+ /* Normal, non-resident data stream. */
return ntfs_write_block(page, wbc);
}
/*
- * Attribute is resident, implying it is not compressed, encrypted,
- * sparse, or mst protected. This also means the attribute is smaller
- * than an mft record and hence smaller than a page, so can simply
- * return error on any pages with index above 0.
+ * Attribute is resident, implying it is not compressed, encrypted, or
+ * mst protected. This also means the attribute is smaller than an mft
+ * record and hence smaller than a page, so can simply return error on
+ * any pages with index above 0. Note the attribute can actually be
+ * marked compressed but if it is resident the actual data is not
+ * compressed so we are ok to ignore the compressed flag here.
*/
BUG_ON(page_has_buffers(page));
BUG_ON(!PageUptodate(page));
@@ -1379,30 +1443,14 @@ retry_writepage:
BUG_ON(PageWriteback(page));
set_page_writeback(page);
unlock_page(page);
-
/*
- * Here, we don't need to zero the out of bounds area everytime because
- * the below memcpy() already takes care of the mmap-at-end-of-file
- * requirements. If the file is converted to a non-resident one, then
- * the code path use is switched to the non-resident one where the
- * zeroing happens on each ntfs_writepage() invocation.
- *
- * The above also applies nicely when i_size is decreased.
- *
- * When i_size is increased, the memory between the old and new i_size
- * _must_ be zeroed (or overwritten with new data). Otherwise we will
- * expose data to userspace/disk which should never have been exposed.
- *
- * FIXME: Ensure that i_size increases do the zeroing/overwriting and
- * if we cannot guarantee that, then enable the zeroing below. If the
- * zeroing below is enabled, we MUST move the unlock_page() from above
- * to after the kunmap_atomic(), i.e. just before the
- * end_page_writeback().
- * UPDATE: ntfs_prepare/commit_write() do the zeroing on i_size
- * increases for resident attributes so those are ok.
- * TODO: ntfs_truncate(), others?
+ * Here, we do not need to zero the out of bounds area everytime
+ * because the below memcpy() already takes care of the
+ * mmap-at-end-of-file requirements. If the file is converted to a
+ * non-resident one, then the code path use is switched to the
+ * non-resident one where the zeroing happens on each ntfs_writepage()
+ * invocation.
*/
-
attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
i_size = i_size_read(vi);
if (unlikely(attr_len > i_size)) {
@@ -1680,27 +1728,25 @@ lock_retry_remap:
if (likely(!err))
goto lock_retry_remap;
rl = NULL;
- lcn = err;
} else if (!rl)
up_read(&ni->runlist.lock);
/*
* Failed to map the buffer, even after
* retrying.
*/
+ if (!err)
+ err = -EIO;
bh->b_blocknr = -1;
ntfs_error(vol->sb, "Failed to write to inode "
"0x%lx, attribute type 0x%x, "
"vcn 0x%llx, offset 0x%x "
"because its location on disk "
"could not be determined%s "
- "(error code %lli).",
+ "(error code %i).",
ni->mft_no, ni->type,
(unsigned long long)vcn,
vcn_ofs, is_retry ? " even "
- "after retrying" : "",
- (long long)lcn);
- if (!err)
- err = -EIO;
+ "after retrying" : "", err);
goto err_out;
}
/* We now have a successful remap, i.e. lcn >= 0. */
@@ -2356,6 +2402,7 @@ void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs) {
buffers_to_free = bh;
}
bh = head = page_buffers(page);
+ BUG_ON(!bh);
do {
bh_ofs = bh_offset(bh);
if (bh_ofs + bh_size <= ofs)
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-17 23:00:23 +0300