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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-24 07:08:41 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-24 07:08:41 -0700
commit1aef882f023eb7c24d6d77f001bd0ba956fdd861 (patch)
tree735c1043f817a8bc9f31fadd224131b3207eebd2 /fs/xfs/xfs_file.c
parentd869844bd081081bf537e806a44811884230643e (diff)
parent542c311813d5cb2e6f0dfa9557f41c829b8fb6a0 (diff)
downloadop-kernel-dev-1aef882f023eb7c24d6d77f001bd0ba956fdd861.zip
op-kernel-dev-1aef882f023eb7c24d6d77f001bd0ba956fdd861.tar.gz
Merge tag 'xfs-for-linus-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs update from Dave Chinner: "This update contains: - RENAME_WHITEOUT support - conversion of per-cpu superblock accounting to use generic counters - new inode mmap lock so that we can lock page faults out of truncate, hole punch and other direct extent manipulation functions to avoid racing mmap writes from causing data corruption - rework of direct IO submission and completion to solve data corruption issue when running concurrent extending DIO writes. Also solves problem of running IO completion transactions in interrupt context during size extending AIO writes. - FALLOC_FL_INSERT_RANGE support for inserting holes into a file via direct extent manipulation to avoid needing to copy data within the file - attribute block header field overflow fix for 64k block size filesystems - Lots of changes to log messaging to be more informative and concise when errors occur. Also prevent a lot of unnecessary log spamming due to cascading failures in error conditions. - lots of cleanups and bug fixes One thing of note is the direct IO fixes that we merged last week after the window opened. Even though a little late, they fix a user reported data corruption and have been pretty well tested. I figured there was not much point waiting another 2 weeks for -rc1 to be released just so I could send them to you..." * tag 'xfs-for-linus-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (49 commits) xfs: using generic_file_direct_write() is unnecessary xfs: direct IO EOF zeroing needs to drain AIO xfs: DIO write completion size updates race xfs: DIO writes within EOF don't need an ioend xfs: handle DIO overwrite EOF update completion correctly xfs: DIO needs an ioend for writes xfs: move DIO mapping size calculation xfs: factor DIO write mapping from get_blocks xfs: unlock i_mutex in xfs_break_layouts xfs: kill unnecessary firstused overflow check on attr3 leaf removal xfs: use larger in-core attr firstused field and detect overflow xfs: pass attr geometry to attr leaf header conversion functions xfs: disallow ro->rw remount on norecovery mount xfs: xfs_shift_file_space can be static xfs: Add support FALLOC_FL_INSERT_RANGE for fallocate fs: Add support FALLOC_FL_INSERT_RANGE for fallocate xfs: Fix incorrect positive ENOMEM return xfs: xfs_mru_cache_insert() should use GFP_NOFS xfs: %pF is only for function pointers xfs: fix shadow warning in xfs_da3_root_split() ...
Diffstat (limited to 'fs/xfs/xfs_file.c')
-rw-r--r--fs/xfs/xfs_file.c161
1 files changed, 137 insertions, 24 deletions
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 1f12ad0..8121e75 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -559,7 +559,7 @@ restart:
if (error <= 0)
return error;
- error = xfs_break_layouts(inode, iolock);
+ error = xfs_break_layouts(inode, iolock, true);
if (error)
return error;
@@ -569,21 +569,42 @@ restart:
* write. If zeroing is needed and we are currently holding the
* iolock shared, we need to update it to exclusive which implies
* having to redo all checks before.
+ *
+ * We need to serialise against EOF updates that occur in IO
+ * completions here. We want to make sure that nobody is changing the
+ * size while we do this check until we have placed an IO barrier (i.e.
+ * hold the XFS_IOLOCK_EXCL) that prevents new IO from being dispatched.
+ * The spinlock effectively forms a memory barrier once we have the
+ * XFS_IOLOCK_EXCL so we are guaranteed to see the latest EOF value
+ * and hence be able to correctly determine if we need to run zeroing.
*/
+ spin_lock(&ip->i_flags_lock);
if (iocb->ki_pos > i_size_read(inode)) {
bool zero = false;
+ spin_unlock(&ip->i_flags_lock);
if (*iolock == XFS_IOLOCK_SHARED) {
xfs_rw_iunlock(ip, *iolock);
*iolock = XFS_IOLOCK_EXCL;
xfs_rw_ilock(ip, *iolock);
iov_iter_reexpand(from, count);
+
+ /*
+ * We now have an IO submission barrier in place, but
+ * AIO can do EOF updates during IO completion and hence
+ * we now need to wait for all of them to drain. Non-AIO
+ * DIO will have drained before we are given the
+ * XFS_IOLOCK_EXCL, and so for most cases this wait is a
+ * no-op.
+ */
+ inode_dio_wait(inode);
goto restart;
}
error = xfs_zero_eof(ip, iocb->ki_pos, i_size_read(inode), &zero);
if (error)
return error;
- }
+ } else
+ spin_unlock(&ip->i_flags_lock);
/*
* Updating the timestamps will grab the ilock again from
@@ -645,6 +666,8 @@ xfs_file_dio_aio_write(
int iolock;
size_t count = iov_iter_count(from);
loff_t pos = iocb->ki_pos;
+ loff_t end;
+ struct iov_iter data;
struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ?
mp->m_rtdev_targp : mp->m_ddev_targp;
@@ -685,10 +708,11 @@ xfs_file_dio_aio_write(
goto out;
count = iov_iter_count(from);
pos = iocb->ki_pos;
+ end = pos + count - 1;
if (mapping->nrpages) {
ret = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
- pos, pos + count - 1);
+ pos, end);
if (ret)
goto out;
/*
@@ -698,7 +722,7 @@ xfs_file_dio_aio_write(
*/
ret = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
pos >> PAGE_CACHE_SHIFT,
- (pos + count - 1) >> PAGE_CACHE_SHIFT);
+ end >> PAGE_CACHE_SHIFT);
WARN_ON_ONCE(ret);
ret = 0;
}
@@ -715,8 +739,22 @@ xfs_file_dio_aio_write(
}
trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0);
- ret = generic_file_direct_write(iocb, from, pos);
+ data = *from;
+ ret = mapping->a_ops->direct_IO(iocb, &data, pos);
+
+ /* see generic_file_direct_write() for why this is necessary */
+ if (mapping->nrpages) {
+ invalidate_inode_pages2_range(mapping,
+ pos >> PAGE_CACHE_SHIFT,
+ end >> PAGE_CACHE_SHIFT);
+ }
+
+ if (ret > 0) {
+ pos += ret;
+ iov_iter_advance(from, ret);
+ iocb->ki_pos = pos;
+ }
out:
xfs_rw_iunlock(ip, iolock);
@@ -822,6 +860,11 @@ xfs_file_write_iter(
return ret;
}
+#define XFS_FALLOC_FL_SUPPORTED \
+ (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
+ FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
+ FALLOC_FL_INSERT_RANGE)
+
STATIC long
xfs_file_fallocate(
struct file *file,
@@ -835,18 +878,21 @@ xfs_file_fallocate(
enum xfs_prealloc_flags flags = 0;
uint iolock = XFS_IOLOCK_EXCL;
loff_t new_size = 0;
+ bool do_file_insert = 0;
if (!S_ISREG(inode->i_mode))
return -EINVAL;
- if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
- FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
+ if (mode & ~XFS_FALLOC_FL_SUPPORTED)
return -EOPNOTSUPP;
xfs_ilock(ip, iolock);
- error = xfs_break_layouts(inode, &iolock);
+ error = xfs_break_layouts(inode, &iolock, false);
if (error)
goto out_unlock;
+ xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
+ iolock |= XFS_MMAPLOCK_EXCL;
+
if (mode & FALLOC_FL_PUNCH_HOLE) {
error = xfs_free_file_space(ip, offset, len);
if (error)
@@ -873,6 +919,27 @@ xfs_file_fallocate(
error = xfs_collapse_file_space(ip, offset, len);
if (error)
goto out_unlock;
+ } else if (mode & FALLOC_FL_INSERT_RANGE) {
+ unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
+
+ new_size = i_size_read(inode) + len;
+ if (offset & blksize_mask || len & blksize_mask) {
+ error = -EINVAL;
+ goto out_unlock;
+ }
+
+ /* check the new inode size does not wrap through zero */
+ if (new_size > inode->i_sb->s_maxbytes) {
+ error = -EFBIG;
+ goto out_unlock;
+ }
+
+ /* Offset should be less than i_size */
+ if (offset >= i_size_read(inode)) {
+ error = -EINVAL;
+ goto out_unlock;
+ }
+ do_file_insert = 1;
} else {
flags |= XFS_PREALLOC_SET;
@@ -907,8 +974,19 @@ xfs_file_fallocate(
iattr.ia_valid = ATTR_SIZE;
iattr.ia_size = new_size;
error = xfs_setattr_size(ip, &iattr);
+ if (error)
+ goto out_unlock;
}
+ /*
+ * Perform hole insertion now that the file size has been
+ * updated so that if we crash during the operation we don't
+ * leave shifted extents past EOF and hence losing access to
+ * the data that is contained within them.
+ */
+ if (do_file_insert)
+ error = xfs_insert_file_space(ip, offset, len);
+
out_unlock:
xfs_iunlock(ip, iolock);
return error;
@@ -997,20 +1075,6 @@ xfs_file_mmap(
}
/*
- * mmap()d file has taken write protection fault and is being made
- * writable. We can set the page state up correctly for a writable
- * page, which means we can do correct delalloc accounting (ENOSPC
- * checking!) and unwritten extent mapping.
- */
-STATIC int
-xfs_vm_page_mkwrite(
- struct vm_area_struct *vma,
- struct vm_fault *vmf)
-{
- return block_page_mkwrite(vma, vmf, xfs_get_blocks);
-}
-
-/*
* This type is designed to indicate the type of offset we would like
* to search from page cache for xfs_seek_hole_data().
*/
@@ -1385,6 +1449,55 @@ xfs_file_llseek(
}
}
+/*
+ * Locking for serialisation of IO during page faults. This results in a lock
+ * ordering of:
+ *
+ * mmap_sem (MM)
+ * i_mmap_lock (XFS - truncate serialisation)
+ * page_lock (MM)
+ * i_lock (XFS - extent map serialisation)
+ */
+STATIC int
+xfs_filemap_fault(
+ struct vm_area_struct *vma,
+ struct vm_fault *vmf)
+{
+ struct xfs_inode *ip = XFS_I(vma->vm_file->f_mapping->host);
+ int error;
+
+ trace_xfs_filemap_fault(ip);
+
+ xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
+ error = filemap_fault(vma, vmf);
+ xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
+
+ return error;
+}
+
+/*
+ * mmap()d file has taken write protection fault and is being made writable. We
+ * can set the page state up correctly for a writable page, which means we can
+ * do correct delalloc accounting (ENOSPC checking!) and unwritten extent
+ * mapping.
+ */
+STATIC int
+xfs_filemap_page_mkwrite(
+ struct vm_area_struct *vma,
+ struct vm_fault *vmf)
+{
+ struct xfs_inode *ip = XFS_I(vma->vm_file->f_mapping->host);
+ int error;
+
+ trace_xfs_filemap_page_mkwrite(ip);
+
+ xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
+ error = block_page_mkwrite(vma, vmf, xfs_get_blocks);
+ xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
+
+ return error;
+}
+
const struct file_operations xfs_file_operations = {
.llseek = xfs_file_llseek,
.read_iter = xfs_file_read_iter,
@@ -1415,7 +1528,7 @@ const struct file_operations xfs_dir_file_operations = {
};
static const struct vm_operations_struct xfs_file_vm_ops = {
- .fault = filemap_fault,
+ .fault = xfs_filemap_fault,
.map_pages = filemap_map_pages,
- .page_mkwrite = xfs_vm_page_mkwrite,
+ .page_mkwrite = xfs_filemap_page_mkwrite,
};
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