NTFS: - Fix bug in fs/ntfs/attrib.c::ntfs_find_vcn_nolock() where after (c0c1cc0e) · Commits · 戴 / test

fs/ntfs/ChangeLog

+5 −0

Original line number	Diff line number	Diff line
		@@ -92,6 +92,11 @@ ToDo/Notes:
		non-resident in fs/ntfs/attrib.c::ntfs_attr_can_be_non_resident().
		- Add fs/ntfs/attrib.c::ntfs_attr_vcn_to_lcn_nolock() used by the new
		write code.
		- Fix bug in fs/ntfs/attrib.c::ntfs_find_vcn_nolock() where after
		dropping the read lock and taking the write lock we were not checking
		whether someone else did not already do the work we wanted to do.
		- Rename fs/ntfs/attrib.c::ntfs_find_vcn_nolock() to
		ntfs_attr_find_vcn_nolock() and update all callers.

		2.1.22 - Many bug and race fixes and error handling improvements.

fs/ntfs/attrib.c

+17 −12

Original line number	Diff line number	Diff line
		@@ -193,19 +193,19 @@ retry_remap:
		}

		/**
		* ntfs_find_vcn_nolock - find a vcn in the runlist described by an ntfs inode
		* ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode
		* @ni: ntfs inode describing the runlist to search
		* @vcn: vcn to find
		* @write_locked: true if the runlist is locked for writing
		*
		* Find the virtual cluster number @vcn in the runlist described by the ntfs
		* inode @ni and return the address of the runlist element containing the @vcn.
		* The runlist is left locked and the caller has to unlock it. In the error
		* case, the runlist is left in the same locking state as on entry.
		*
		* Note if @write_locked is FALSE the lock may be dropped inside the function
		* so you cannot rely on the runlist still being the same when this function
		* returns.
		* If the @vcn is not mapped yet, the attempt is made to map the attribute
		* extent containing the @vcn and the vcn to lcn conversion is retried.
		*
		* If @write_locked is true the caller has locked the runlist for writing and
		* if false for reading.
		*
		* Note you need to distinguish between the lcn of the returned runlist element
		* being >= 0 and LCN_HOLE. In the later case you have to return zeroes on
		@@ -221,13 +221,12 @@ retry_remap:
		* -ENOMEM - Not enough memory to map runlist.
		* -EIO - Critical error (runlist/file is corrupt, i/o error, etc).
		*
		* Locking: - The runlist must be unlocked on entry.
		* - On failing return, the runlist is unlocked.
		* - On successful return, the runlist is locked. If @need_write us
		* true, it is locked for writing. Otherwise is is locked for
		* reading.
		* Locking: - The runlist must be locked on entry and is left locked on return.
		* - If @write_locked is FALSE, i.e. the runlist is locked for reading,
		* the lock may be dropped inside the function so you cannot rely on
		* the runlist still being the same when this function returns.
		*/
		runlist_element ntfs_find_vcn_nolock(ntfs_inode ni, const VCN vcn,
		runlist_element ntfs_attr_find_vcn_nolock(ntfs_inode ni, const VCN vcn,
		const BOOL write_locked)
		{
		runlist_element *rl;
		@@ -268,6 +267,12 @@ retry_remap:
		if (!write_locked) {
		up_read(&ni->runlist.lock);
		down_write(&ni->runlist.lock);
		if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
		LCN_RL_NOT_MAPPED)) {
		up_write(&ni->runlist.lock);
		down_read(&ni->runlist.lock);
		goto retry_remap;
		}
		}
		err = ntfs_map_runlist_nolock(ni, vcn);
		if (!write_locked) {

fs/ntfs/attrib.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -66,8 +66,8 @@ extern int ntfs_map_runlist(ntfs_inode *ni, VCN vcn);
		extern LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn,
		const BOOL write_locked);

		extern runlist_element ntfs_find_vcn_nolock(ntfs_inode ni, const VCN vcn,
		const BOOL write_locked);
		extern runlist_element ntfs_attr_find_vcn_nolock(ntfs_inode ni,
		const VCN vcn, const BOOL write_locked);

		int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name,
		const u32 name_len, const IGNORE_CASE_BOOL ic,

fs/ntfs/lcnalloc.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -850,7 +850,7 @@ s64 __ntfs_cluster_free(struct inode *vi, const VCN start_vcn, s64 count,

		/* This returns with ni->runlist locked for reading on success. */
		down_read(&ni->runlist.lock);
		rl = ntfs_find_vcn_nolock(ni, start_vcn, FALSE);
		rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, FALSE);
		if (IS_ERR(rl)) {
		if (!is_rollback)
		ntfs_error(vol->sb, "Failed to find first runlist "
		@@ -904,7 +904,7 @@ s64 __ntfs_cluster_free(struct inode *vi, const VCN start_vcn, s64 count,

		/* Attempt to map runlist. */
		vcn = rl->vcn;
		rl = ntfs_find_vcn_nolock(ni, vcn, FALSE);
		rl = ntfs_attr_find_vcn_nolock(ni, vcn, FALSE);
		if (IS_ERR(rl)) {
		err = PTR_ERR(rl);
		if (!is_rollback)

fs/ntfs/mft.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -1297,7 +1297,7 @@ static int ntfs_mft_bitmap_extend_allocation_nolock(ntfs_volume *vol)
		read_lock_irqsave(&mftbmp_ni->size_lock, flags);
		ll = mftbmp_ni->allocated_size;
		read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
		rl = ntfs_find_vcn_nolock(mftbmp_ni,
		rl = ntfs_attr_find_vcn_nolock(mftbmp_ni,
		(ll - 1) >> vol->cluster_size_bits, TRUE);
		if (unlikely(IS_ERR(rl) \|\| !rl->length \|\| rl->lcn < 0)) {
		up_write(&mftbmp_ni->runlist.lock);
		@@ -1727,8 +1727,8 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
		read_lock_irqsave(&mft_ni->size_lock, flags);
		ll = mft_ni->allocated_size;
		read_unlock_irqrestore(&mft_ni->size_lock, flags);
		rl = ntfs_find_vcn_nolock(mft_ni, (ll - 1) >> vol->cluster_size_bits,
		TRUE);
		rl = ntfs_attr_find_vcn_nolock(mft_ni,
		(ll - 1) >> vol->cluster_size_bits, TRUE);
		if (unlikely(IS_ERR(rl) \|\| !rl->length \|\| rl->lcn < 0)) {
		up_write(&mft_ni->runlist.lock);
		ntfs_error(vol->sb, "Failed to determine last allocated "

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