/*
* file.c - NTFS kernel file operations. Part of the Linux-NTFS project.
*
- * Copyright (c) 2001-2014 Anton Altaparmakov and Tuxera Inc.
+ * Copyright (c) 2001-2015 Anton Altaparmakov and Tuxera Inc.
*
* This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
return err;
}
-/**
- * ntfs_fault_in_pages_readable -
- *
- * Fault a number of userspace pages into pagetables.
- *
- * Unlike include/linux/pagemap.h::fault_in_pages_readable(), this one copes
- * with more than two userspace pages as well as handling the single page case
- * elegantly.
- *
- * If you find this difficult to understand, then think of the while loop being
- * the following code, except that we do without the integer variable ret:
- *
- * do {
- * ret = __get_user(c, uaddr);
- * uaddr += PAGE_SIZE;
- * } while (!ret && uaddr < end);
- *
- * Note, the final __get_user() may well run out-of-bounds of the user buffer,
- * but _not_ out-of-bounds of the page the user buffer belongs to, and since
- * this is only a read and not a write, and since it is still in the same page,
- * it should not matter and this makes the code much simpler.
- */
-static inline void ntfs_fault_in_pages_readable(const char __user *uaddr,
- int bytes)
+static ssize_t ntfs_prepare_file_for_write(struct file *file, loff_t *ppos,
+ size_t *count)
{
- const char __user *end;
- volatile char c;
-
- /* Set @end to the first byte outside the last page we care about. */
- end = (const char __user*)PAGE_ALIGN((unsigned long)uaddr + bytes);
-
- while (!__get_user(c, uaddr) && (uaddr += PAGE_SIZE, uaddr < end))
- ;
-}
-
-/**
- * ntfs_fault_in_pages_readable_iovec -
- *
- * Same as ntfs_fault_in_pages_readable() but operates on an array of iovecs.
- */
-static inline void ntfs_fault_in_pages_readable_iovec(const struct iovec *iov,
- size_t iov_ofs, int bytes)
-{
- do {
- const char __user *buf;
- unsigned len;
+ loff_t pos;
+ s64 end, ll;
+ ssize_t err;
+ unsigned long flags;
+ struct inode *vi = file_inode(file);
+ ntfs_inode *base_ni, *ni = NTFS_I(vi);
+ ntfs_volume *vol = ni->vol;
- buf = iov->iov_base + iov_ofs;
- len = iov->iov_len - iov_ofs;
- if (len > bytes)
- len = bytes;
- ntfs_fault_in_pages_readable(buf, len);
- bytes -= len;
- iov++;
- iov_ofs = 0;
- } while (bytes);
+ ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, pos "
+ "0x%llx, count 0x%lx.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type),
+ (unsigned long long)*ppos, (unsigned long)*count);
+ /* We can write back this queue in page reclaim. */
+ current->backing_dev_info = inode_to_bdi(vi);
+ err = generic_write_checks(file, ppos, count, S_ISBLK(vi->i_mode));
+ if (unlikely(err))
+ goto out;
+ /*
+ * All checks have passed. Before we start doing any writing we want
+ * to abort any totally illegal writes.
+ */
+ BUG_ON(NInoMstProtected(ni));
+ BUG_ON(ni->type != AT_DATA);
+ /* If file is encrypted, deny access, just like NT4. */
+ if (NInoEncrypted(ni)) {
+ /* Only $DATA attributes can be encrypted. */
+ /*
+ * Reminder for later: Encrypted files are _always_
+ * non-resident so that the content can always be encrypted.
+ */
+ ntfs_debug("Denying write access to encrypted file.");
+ err = -EACCES;
+ goto out;
+ }
+ if (NInoCompressed(ni)) {
+ /* Only unnamed $DATA attribute can be compressed. */
+ BUG_ON(ni->name_len);
+ /*
+ * Reminder for later: If resident, the data is not actually
+ * compressed. Only on the switch to non-resident does
+ * compression kick in. This is in contrast to encrypted files
+ * (see above).
+ */
+ ntfs_error(vi->i_sb, "Writing to compressed files is not "
+ "implemented yet. Sorry.");
+ err = -EOPNOTSUPP;
+ goto out;
+ }
+ if (*count == 0)
+ goto out;
+ base_ni = ni;
+ if (NInoAttr(ni))
+ base_ni = ni->ext.base_ntfs_ino;
+ err = file_remove_suid(file);
+ if (unlikely(err))
+ goto out;
+ /*
+ * Our ->update_time method always succeeds thus file_update_time()
+ * cannot fail either so there is no need to check the return code.
+ */
+ file_update_time(file);
+ pos = *ppos;
+ /* The first byte after the last cluster being written to. */
+ end = (pos + *count + vol->cluster_size_mask) &
+ ~(u64)vol->cluster_size_mask;
+ /*
+ * If the write goes beyond the allocated size, extend the allocation
+ * to cover the whole of the write, rounded up to the nearest cluster.
+ */
+ read_lock_irqsave(&ni->size_lock, flags);
+ ll = ni->allocated_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ if (end > ll) {
+ /*
+ * Extend the allocation without changing the data size.
+ *
+ * Note we ensure the allocation is big enough to at least
+ * write some data but we do not require the allocation to be
+ * complete, i.e. it may be partial.
+ */
+ ll = ntfs_attr_extend_allocation(ni, end, -1, pos);
+ if (likely(ll >= 0)) {
+ BUG_ON(pos >= ll);
+ /* If the extension was partial truncate the write. */
+ if (end > ll) {
+ ntfs_debug("Truncating write to inode 0x%lx, "
+ "attribute type 0x%x, because "
+ "the allocation was only "
+ "partially extended.",
+ vi->i_ino, (unsigned)
+ le32_to_cpu(ni->type));
+ *count = ll - pos;
+ }
+ } else {
+ err = ll;
+ read_lock_irqsave(&ni->size_lock, flags);
+ ll = ni->allocated_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ /* Perform a partial write if possible or fail. */
+ if (pos < ll) {
+ ntfs_debug("Truncating write to inode 0x%lx "
+ "attribute type 0x%x, because "
+ "extending the allocation "
+ "failed (error %d).",
+ vi->i_ino, (unsigned)
+ le32_to_cpu(ni->type),
+ (int)-err);
+ *count = ll - pos;
+ } else {
+ if (err != -ENOSPC)
+ ntfs_error(vi->i_sb, "Cannot perform "
+ "write to inode "
+ "0x%lx, attribute "
+ "type 0x%x, because "
+ "extending the "
+ "allocation failed "
+ "(error %ld).",
+ vi->i_ino, (unsigned)
+ le32_to_cpu(ni->type),
+ (long)-err);
+ else
+ ntfs_debug("Cannot perform write to "
+ "inode 0x%lx, "
+ "attribute type 0x%x, "
+ "because there is not "
+ "space left.",
+ vi->i_ino, (unsigned)
+ le32_to_cpu(ni->type));
+ goto out;
+ }
+ }
+ }
+ /*
+ * If the write starts beyond the initialized size, extend it up to the
+ * beginning of the write and initialize all non-sparse space between
+ * the old initialized size and the new one. This automatically also
+ * increments the vfs inode->i_size to keep it above or equal to the
+ * initialized_size.
+ */
+ read_lock_irqsave(&ni->size_lock, flags);
+ ll = ni->initialized_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ if (pos > ll) {
+ /*
+ * Wait for ongoing direct i/o to complete before proceeding.
+ * New direct i/o cannot start as we hold i_mutex.
+ */
+ inode_dio_wait(vi);
+ err = ntfs_attr_extend_initialized(ni, pos);
+ if (unlikely(err < 0))
+ ntfs_error(vi->i_sb, "Cannot perform write to inode "
+ "0x%lx, attribute type 0x%x, because "
+ "extending the initialized size "
+ "failed (error %d).", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type),
+ (int)-err);
+ }
+out:
+ return err;
}
/**
goto err_out;
}
}
- err = add_to_page_cache_lru(*cached_page, mapping, index,
- GFP_KERNEL);
+ err = add_to_page_cache_lru(*cached_page, mapping,
+ index, GFP_KERNEL);
if (unlikely(err)) {
if (err == -EEXIST)
continue;
return err;
}
-/*
- * Copy as much as we can into the pages and return the number of bytes which
- * were successfully copied. If a fault is encountered then clear the pages
- * out to (ofs + bytes) and return the number of bytes which were copied.
- */
-static inline size_t ntfs_copy_from_user(struct page **pages,
- unsigned nr_pages, unsigned ofs, const char __user *buf,
- size_t bytes)
-{
- struct page **last_page = pages + nr_pages;
- char *addr;
- size_t total = 0;
- unsigned len;
- int left;
-
- do {
- len = PAGE_CACHE_SIZE - ofs;
- if (len > bytes)
- len = bytes;
- addr = kmap_atomic(*pages);
- left = __copy_from_user_inatomic(addr + ofs, buf, len);
- kunmap_atomic(addr);
- if (unlikely(left)) {
- /* Do it the slow way. */
- addr = kmap(*pages);
- left = __copy_from_user(addr + ofs, buf, len);
- kunmap(*pages);
- if (unlikely(left))
- goto err_out;
- }
- total += len;
- bytes -= len;
- if (!bytes)
- break;
- buf += len;
- ofs = 0;
- } while (++pages < last_page);
-out:
- return total;
-err_out:
- total += len - left;
- /* Zero the rest of the target like __copy_from_user(). */
- while (++pages < last_page) {
- bytes -= len;
- if (!bytes)
- break;
- len = PAGE_CACHE_SIZE;
- if (len > bytes)
- len = bytes;
- zero_user(*pages, 0, len);
- }
- goto out;
-}
-
-static size_t __ntfs_copy_from_user_iovec_inatomic(char *vaddr,
- const struct iovec *iov, size_t iov_ofs, size_t bytes)
-{
- size_t total = 0;
-
- while (1) {
- const char __user *buf = iov->iov_base + iov_ofs;
- unsigned len;
- size_t left;
-
- len = iov->iov_len - iov_ofs;
- if (len > bytes)
- len = bytes;
- left = __copy_from_user_inatomic(vaddr, buf, len);
- total += len;
- bytes -= len;
- vaddr += len;
- if (unlikely(left)) {
- total -= left;
- break;
- }
- if (!bytes)
- break;
- iov++;
- iov_ofs = 0;
- }
- return total;
-}
-
-static inline void ntfs_set_next_iovec(const struct iovec **iovp,
- size_t *iov_ofsp, size_t bytes)
-{
- const struct iovec *iov = *iovp;
- size_t iov_ofs = *iov_ofsp;
-
- while (bytes) {
- unsigned len;
-
- len = iov->iov_len - iov_ofs;
- if (len > bytes)
- len = bytes;
- bytes -= len;
- iov_ofs += len;
- if (iov->iov_len == iov_ofs) {
- iov++;
- iov_ofs = 0;
- }
- }
- *iovp = iov;
- *iov_ofsp = iov_ofs;
-}
-
-/*
- * This has the same side-effects and return value as ntfs_copy_from_user().
- * The difference is that on a fault we need to memset the remainder of the
- * pages (out to offset + bytes), to emulate ntfs_copy_from_user()'s
- * single-segment behaviour.
- *
- * We call the same helper (__ntfs_copy_from_user_iovec_inatomic()) both when
- * atomic and when not atomic. This is ok because it calls
- * __copy_from_user_inatomic() and it is ok to call this when non-atomic. In
- * fact, the only difference between __copy_from_user_inatomic() and
- * __copy_from_user() is that the latter calls might_sleep() and the former
- * should not zero the tail of the buffer on error. And on many architectures
- * __copy_from_user_inatomic() is just defined to __copy_from_user() so it
- * makes no difference at all on those architectures.
- */
-static inline size_t ntfs_copy_from_user_iovec(struct page **pages,
- unsigned nr_pages, unsigned ofs, const struct iovec **iov,
- size_t *iov_ofs, size_t bytes)
-{
- struct page **last_page = pages + nr_pages;
- char *addr;
- size_t copied, len, total = 0;
-
- do {
- len = PAGE_CACHE_SIZE - ofs;
- if (len > bytes)
- len = bytes;
- addr = kmap_atomic(*pages);
- copied = __ntfs_copy_from_user_iovec_inatomic(addr + ofs,
- *iov, *iov_ofs, len);
- kunmap_atomic(addr);
- if (unlikely(copied != len)) {
- /* Do it the slow way. */
- addr = kmap(*pages);
- copied = __ntfs_copy_from_user_iovec_inatomic(addr +
- ofs, *iov, *iov_ofs, len);
- if (unlikely(copied != len))
- goto err_out;
- kunmap(*pages);
- }
- total += len;
- ntfs_set_next_iovec(iov, iov_ofs, len);
- bytes -= len;
- if (!bytes)
- break;
- ofs = 0;
- } while (++pages < last_page);
-out:
- return total;
-err_out:
- BUG_ON(copied > len);
- /* Zero the rest of the target like __copy_from_user(). */
- memset(addr + ofs + copied, 0, len - copied);
- kunmap(*pages);
- total += copied;
- ntfs_set_next_iovec(iov, iov_ofs, copied);
- while (++pages < last_page) {
- bytes -= len;
- if (!bytes)
- break;
- len = PAGE_CACHE_SIZE;
- if (len > bytes)
- len = bytes;
- zero_user(*pages, 0, len);
- }
- goto out;
-}
-
static inline void ntfs_flush_dcache_pages(struct page **pages,
unsigned nr_pages)
{
return err;
}
-static void ntfs_write_failed(struct address_space *mapping, loff_t to)
+/*
+ * Copy as much as we can into the pages and return the number of bytes which
+ * were successfully copied. If a fault is encountered then clear the pages
+ * out to (ofs + bytes) and return the number of bytes which were copied.
+ */
+static size_t ntfs_copy_from_user_iter(struct page **pages, unsigned nr_pages,
+ unsigned ofs, struct iov_iter *i, size_t bytes)
{
- struct inode *inode = mapping->host;
+ struct page **last_page = pages + nr_pages;
+ size_t total = 0;
+ struct iov_iter data = *i;
+ unsigned len, copied;
- if (to > inode->i_size) {
- truncate_pagecache(inode, inode->i_size);
- ntfs_truncate_vfs(inode);
- }
+ do {
+ len = PAGE_CACHE_SIZE - ofs;
+ if (len > bytes)
+ len = bytes;
+ copied = iov_iter_copy_from_user_atomic(*pages, &data, ofs,
+ len);
+ total += copied;
+ bytes -= copied;
+ if (!bytes)
+ break;
+ iov_iter_advance(&data, copied);
+ if (copied < len)
+ goto err;
+ ofs = 0;
+ } while (++pages < last_page);
+out:
+ return total;
+err:
+ /* Zero the rest of the target like __copy_from_user(). */
+ len = PAGE_CACHE_SIZE - copied;
+ do {
+ if (len > bytes)
+ len = bytes;
+ zero_user(*pages, copied, len);
+ bytes -= len;
+ copied = 0;
+ len = PAGE_CACHE_SIZE;
+ } while (++pages < last_page);
+ goto out;
}
/**
- * ntfs_file_buffered_write -
- *
- * Locking: The vfs is holding ->i_mutex on the inode.
+ * ntfs_perform_write - perform buffered write to a file
+ * @file: file to write to
+ * @i: iov_iter with data to write
+ * @pos: byte offset in file at which to begin writing to
*/
-static ssize_t ntfs_file_buffered_write(struct kiocb *iocb,
- const struct iovec *iov, unsigned long nr_segs,
- loff_t pos, loff_t *ppos, size_t count)
+static ssize_t ntfs_perform_write(struct file *file, struct iov_iter *i,
+ loff_t pos)
{
- struct file *file = iocb->ki_filp;
struct address_space *mapping = file->f_mapping;
struct inode *vi = mapping->host;
ntfs_inode *ni = NTFS_I(vi);
ntfs_volume *vol = ni->vol;
struct page *pages[NTFS_MAX_PAGES_PER_CLUSTER];
struct page *cached_page = NULL;
- char __user *buf = NULL;
- s64 end, ll;
VCN last_vcn;
LCN lcn;
- unsigned long flags;
- size_t bytes, iov_ofs = 0; /* Offset in the current iovec. */
- ssize_t status, written;
+ size_t bytes;
+ ssize_t status, written = 0;
unsigned nr_pages;
- int err;
- ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, "
- "pos 0x%llx, count 0x%lx.",
- vi->i_ino, (unsigned)le32_to_cpu(ni->type),
- (unsigned long long)pos, (unsigned long)count);
- if (unlikely(!count))
- return 0;
- BUG_ON(NInoMstProtected(ni));
- /*
- * If the attribute is not an index root and it is encrypted or
- * compressed, we cannot write to it yet. Note we need to check for
- * AT_INDEX_ALLOCATION since this is the type of both directory and
- * index inodes.
- */
- if (ni->type != AT_INDEX_ALLOCATION) {
- /* If file is encrypted, deny access, just like NT4. */
- if (NInoEncrypted(ni)) {
- /*
- * Reminder for later: Encrypted files are _always_
- * non-resident so that the content can always be
- * encrypted.
- */
- ntfs_debug("Denying write access to encrypted file.");
- return -EACCES;
- }
- if (NInoCompressed(ni)) {
- /* Only unnamed $DATA attribute can be compressed. */
- BUG_ON(ni->type != AT_DATA);
- BUG_ON(ni->name_len);
- /*
- * Reminder for later: If resident, the data is not
- * actually compressed. Only on the switch to non-
- * resident does compression kick in. This is in
- * contrast to encrypted files (see above).
- */
- ntfs_error(vi->i_sb, "Writing to compressed files is "
- "not implemented yet. Sorry.");
- return -EOPNOTSUPP;
- }
- }
+ ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, pos "
+ "0x%llx, count 0x%lx.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type),
+ (unsigned long long)pos,
+ (unsigned long)iov_iter_count(i));
/*
* If a previous ntfs_truncate() failed, repeat it and abort if it
* fails again.
*/
if (unlikely(NInoTruncateFailed(ni))) {
+ int err;
+
inode_dio_wait(vi);
err = ntfs_truncate(vi);
if (err || NInoTruncateFailed(ni)) {
return err;
}
}
- /* The first byte after the write. */
- end = pos + count;
- /*
- * If the write goes beyond the allocated size, extend the allocation
- * to cover the whole of the write, rounded up to the nearest cluster.
- */
- read_lock_irqsave(&ni->size_lock, flags);
- ll = ni->allocated_size;
- read_unlock_irqrestore(&ni->size_lock, flags);
- if (end > ll) {
- /* Extend the allocation without changing the data size. */
- ll = ntfs_attr_extend_allocation(ni, end, -1, pos);
- if (likely(ll >= 0)) {
- BUG_ON(pos >= ll);
- /* If the extension was partial truncate the write. */
- if (end > ll) {
- ntfs_debug("Truncating write to inode 0x%lx, "
- "attribute type 0x%x, because "
- "the allocation was only "
- "partially extended.",
- vi->i_ino, (unsigned)
- le32_to_cpu(ni->type));
- end = ll;
- count = ll - pos;
- }
- } else {
- err = ll;
- read_lock_irqsave(&ni->size_lock, flags);
- ll = ni->allocated_size;
- read_unlock_irqrestore(&ni->size_lock, flags);
- /* Perform a partial write if possible or fail. */
- if (pos < ll) {
- ntfs_debug("Truncating write to inode 0x%lx, "
- "attribute type 0x%x, because "
- "extending the allocation "
- "failed (error code %i).",
- vi->i_ino, (unsigned)
- le32_to_cpu(ni->type), err);
- end = ll;
- count = ll - pos;
- } else {
- ntfs_error(vol->sb, "Cannot perform write to "
- "inode 0x%lx, attribute type "
- "0x%x, because extending the "
- "allocation failed (error "
- "code %i).", vi->i_ino,
- (unsigned)
- le32_to_cpu(ni->type), err);
- return err;
- }
- }
- }
- written = 0;
- /*
- * If the write starts beyond the initialized size, extend it up to the
- * beginning of the write and initialize all non-sparse space between
- * the old initialized size and the new one. This automatically also
- * increments the vfs inode->i_size to keep it above or equal to the
- * initialized_size.
- */
- read_lock_irqsave(&ni->size_lock, flags);
- ll = ni->initialized_size;
- read_unlock_irqrestore(&ni->size_lock, flags);
- if (pos > ll) {
- err = ntfs_attr_extend_initialized(ni, pos);
- if (err < 0) {
- ntfs_error(vol->sb, "Cannot perform write to inode "
- "0x%lx, attribute type 0x%x, because "
- "extending the initialized size "
- "failed (error code %i).", vi->i_ino,
- (unsigned)le32_to_cpu(ni->type), err);
- status = err;
- goto err_out;
- }
- }
/*
* Determine the number of pages per cluster for non-resident
* attributes.
nr_pages = 1;
if (vol->cluster_size > PAGE_CACHE_SIZE && NInoNonResident(ni))
nr_pages = vol->cluster_size >> PAGE_CACHE_SHIFT;
- /* Finally, perform the actual write. */
last_vcn = -1;
- if (likely(nr_segs == 1))
- buf = iov->iov_base;
do {
VCN vcn;
pgoff_t idx, start_idx;
vol->cluster_size_bits, false);
up_read(&ni->runlist.lock);
if (unlikely(lcn < LCN_HOLE)) {
- status = -EIO;
if (lcn == LCN_ENOMEM)
status = -ENOMEM;
- else
+ else {
+ status = -EIO;
ntfs_error(vol->sb, "Cannot "
"perform write to "
"inode 0x%lx, "
"is corrupt.",
vi->i_ino, (unsigned)
le32_to_cpu(ni->type));
+ }
break;
}
if (lcn == LCN_HOLE) {
}
}
}
- if (bytes > count)
- bytes = count;
+ if (bytes > iov_iter_count(i))
+ bytes = iov_iter_count(i);
+again:
/*
* Bring in the user page(s) that we will copy from _first_.
* Otherwise there is a nasty deadlock on copying from the same
* pages being swapped out between us bringing them into memory
* and doing the actual copying.
*/
- if (likely(nr_segs == 1))
- ntfs_fault_in_pages_readable(buf, bytes);
- else
- ntfs_fault_in_pages_readable_iovec(iov, iov_ofs, bytes);
+ if (unlikely(iov_iter_fault_in_multipages_readable(i, bytes))) {
+ status = -EFAULT;
+ break;
+ }
/* Get and lock @do_pages starting at index @start_idx. */
status = __ntfs_grab_cache_pages(mapping, start_idx, do_pages,
pages, &cached_page);
status = ntfs_prepare_pages_for_non_resident_write(
pages, do_pages, pos, bytes);
if (unlikely(status)) {
- loff_t i_size;
-
do {
unlock_page(pages[--do_pages]);
page_cache_release(pages[do_pages]);
} while (do_pages);
- /*
- * The write preparation may have instantiated
- * allocated space outside i_size. Trim this
- * off again. We can ignore any errors in this
- * case as we will just be waisting a bit of
- * allocated space, which is not a disaster.
- */
- i_size = i_size_read(vi);
- if (pos + bytes > i_size) {
- ntfs_write_failed(mapping, pos + bytes);
- }
break;
}
}
u = (pos >> PAGE_CACHE_SHIFT) - pages[0]->index;
- if (likely(nr_segs == 1)) {
- copied = ntfs_copy_from_user(pages + u, do_pages - u,
- ofs, buf, bytes);
- buf += copied;
- } else
- copied = ntfs_copy_from_user_iovec(pages + u,
- do_pages - u, ofs, &iov, &iov_ofs,
- bytes);
+ copied = ntfs_copy_from_user_iter(pages + u, do_pages - u, ofs,
+ i, bytes);
ntfs_flush_dcache_pages(pages + u, do_pages - u);
- status = ntfs_commit_pages_after_write(pages, do_pages, pos,
- bytes);
- if (likely(!status)) {
- written += copied;
- count -= copied;
- pos += copied;
- if (unlikely(copied != bytes))
- status = -EFAULT;
+ status = 0;
+ if (likely(copied == bytes)) {
+ status = ntfs_commit_pages_after_write(pages, do_pages,
+ pos, bytes);
+ if (!status)
+ status = bytes;
}
do {
unlock_page(pages[--do_pages]);
page_cache_release(pages[do_pages]);
} while (do_pages);
- if (unlikely(status))
+ if (unlikely(status < 0))
break;
- balance_dirty_pages_ratelimited(mapping);
+ copied = status;
cond_resched();
- } while (count);
-err_out:
- *ppos = pos;
+ if (unlikely(!copied)) {
+ size_t sc;
+
+ /*
+ * We failed to copy anything. Fall back to single
+ * segment length write.
+ *
+ * This is needed to avoid possible livelock in the
+ * case that all segments in the iov cannot be copied
+ * at once without a pagefault.
+ */
+ sc = iov_iter_single_seg_count(i);
+ if (bytes > sc)
+ bytes = sc;
+ goto again;
+ }
+ iov_iter_advance(i, copied);
+ pos += copied;
+ written += copied;
+ balance_dirty_pages_ratelimited(mapping);
+ if (fatal_signal_pending(current)) {
+ status = -EINTR;
+ break;
+ }
+ } while (iov_iter_count(i));
if (cached_page)
page_cache_release(cached_page);
ntfs_debug("Done. Returning %s (written 0x%lx, status %li).",
}
/**
- * ntfs_file_aio_write_nolock -
+ * ntfs_file_write_iter_nolock - write data to a file
+ * @iocb: IO state structure (file, offset, etc.)
+ * @from: iov_iter with data to write
+ *
+ * Basically the same as __generic_file_write_iter() except that it ends
+ * up calling ntfs_perform_write() instead of generic_perform_write() and that
+ * O_DIRECT is not implemented.
*/
-static ssize_t ntfs_file_aio_write_nolock(struct kiocb *iocb,
- const struct iovec *iov, unsigned long nr_segs, loff_t *ppos)
+static ssize_t ntfs_file_write_iter_nolock(struct kiocb *iocb,
+ struct iov_iter *from)
{
struct file *file = iocb->ki_filp;
- struct address_space *mapping = file->f_mapping;
- struct inode *inode = mapping->host;
- loff_t pos;
- size_t count; /* after file limit checks */
- ssize_t written, err;
+ loff_t pos = iocb->ki_pos;
+ ssize_t written = 0;
+ ssize_t err;
+ size_t count = iov_iter_count(from);
- count = iov_length(iov, nr_segs);
- pos = *ppos;
- /* We can write back this queue in page reclaim. */
- current->backing_dev_info = inode_to_bdi(inode);
- written = 0;
- err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
- if (err)
- goto out;
- if (!count)
- goto out;
- err = file_remove_suid(file);
- if (err)
- goto out;
- err = file_update_time(file);
- if (err)
- goto out;
- written = ntfs_file_buffered_write(iocb, iov, nr_segs, pos, ppos,
- count);
-out:
+ err = ntfs_prepare_file_for_write(file, &pos, &count);
+ if (count && !err) {
+ iov_iter_truncate(from, count);
+ written = ntfs_perform_write(file, from, pos);
+ if (likely(written >= 0))
+ iocb->ki_pos = pos + written;
+ }
current->backing_dev_info = NULL;
return written ? written : err;
}
/**
- * ntfs_file_aio_write -
+ * ntfs_file_write_iter - simple wrapper for ntfs_file_write_iter_nolock()
+ * @iocb: IO state structure
+ * @from: iov_iter with data to write
+ *
+ * Basically the same as generic_file_write_iter() except that it ends up
+ * calling ntfs_file_write_iter_nolock() instead of
+ * __generic_file_write_iter().
*/
-static ssize_t ntfs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t pos)
+static ssize_t ntfs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct file *file = iocb->ki_filp;
- struct address_space *mapping = file->f_mapping;
- struct inode *inode = mapping->host;
+ struct inode *vi = file_inode(file);
ssize_t ret;
- BUG_ON(iocb->ki_pos != pos);
-
- mutex_lock(&inode->i_mutex);
- ret = ntfs_file_aio_write_nolock(iocb, iov, nr_segs, &iocb->ki_pos);
- mutex_unlock(&inode->i_mutex);
+ mutex_lock(&vi->i_mutex);
+ ret = ntfs_file_write_iter_nolock(iocb, from);
+ mutex_unlock(&vi->i_mutex);
if (ret > 0) {
- int err = generic_write_sync(file, iocb->ki_pos - ret, ret);
+ ssize_t err;
+
+ err = generic_write_sync(file, iocb->ki_pos - ret, ret);
if (err < 0)
ret = err;
}
#endif /* NTFS_RW */
const struct file_operations ntfs_file_ops = {
- .llseek = generic_file_llseek, /* Seek inside file. */
- .read = new_sync_read, /* Read from file. */
- .read_iter = generic_file_read_iter, /* Async read from file. */
+ .llseek = generic_file_llseek,
+ .read = new_sync_read,
+ .read_iter = generic_file_read_iter,
#ifdef NTFS_RW
- .write = do_sync_write, /* Write to file. */
- .aio_write = ntfs_file_aio_write, /* Async write to file. */
- /*.release = ,*/ /* Last file is closed. See
- fs/ext2/file.c::
- ext2_release_file() for
- how to use this to discard
- preallocated space for
- write opened files. */
- .fsync = ntfs_file_fsync, /* Sync a file to disk. */
- /*.aio_fsync = ,*/ /* Sync all outstanding async
- i/o operations on a
- kiocb. */
+ .write = new_sync_write,
+ .write_iter = ntfs_file_write_iter,
+ .fsync = ntfs_file_fsync,
#endif /* NTFS_RW */
- /*.ioctl = ,*/ /* Perform function on the
- mounted filesystem. */
- .mmap = generic_file_mmap, /* Mmap file. */
- .open = ntfs_file_open, /* Open file. */
- .splice_read = generic_file_splice_read /* Zero-copy data send with
- the data source being on
- the ntfs partition. We do
- not need to care about the
- data destination. */
- /*.sendpage = ,*/ /* Zero-copy data send with
- the data destination being
- on the ntfs partition. We
- do not need to care about
- the data source. */
+ .mmap = generic_file_mmap,
+ .open = ntfs_file_open,
+ .splice_read = generic_file_splice_read,
};
const struct inode_operations ntfs_file_inode_ops = {
git.samba.org / sfrench / cifs-2.6.git / commitdiff