Commit fe768d51 authored by Pavel Shilovsky's avatar Pavel Shilovsky Committed by Steve French
Browse files

CIFS: Return error code when getting file handle for writeback 



Now we just return NULL cifsFileInfo pointer in cases we didn't find
or couldn't reopen a file. This hides errors from cifs_reopen_file()
especially retryable errors which should be handled appropriately.
Create new cifs_get_writable_file() routine that returns error codes
from cifs_reopen_file() and use it in the writeback codepath.

Signed-off-by: default avatarPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent c4b8f657

fs/cifs/cifsproto.h

+3 −0
Original line number Original line Diff line number Diff line
@@ -134,6 +134,9 @@ extern bool is_size_safe_to_change(struct cifsInodeInfo *, __u64 eof); 
extern void cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,

extern void cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,

			    unsigned int bytes_written);

			    unsigned int bytes_written);

extern struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *, bool);

extern struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *, bool);

extern int cifs_get_writable_file(struct cifsInodeInfo *cifs_inode,

				  bool fsuid_only,

				  struct cifsFileInfo **ret_file);

extern struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *, bool);

extern struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *, bool);

extern unsigned int smbCalcSize(void *buf, struct TCP_Server_Info *server);

extern unsigned int smbCalcSize(void *buf, struct TCP_Server_Info *server);

extern int decode_negTokenInit(unsigned char *security_blob, int length,

extern int decode_negTokenInit(unsigned char *security_blob, int length,

fs/cifs/cifssmb.c

+6 −3
Original line number Original line Diff line number Diff line
@@ -2126,9 +2126,12 @@ cifs_writev_requeue(struct cifs_writedata *wdata) 
		wdata2->tailsz = tailsz;

		wdata2->tailsz = tailsz;

		wdata2->bytes = cur_len;

		wdata2->bytes = cur_len;





		wdata2->cfile = find_writable_file(CIFS_I(inode), false);

		rc = cifs_get_writable_file(CIFS_I(inode), false,

					    &wdata2->cfile);

		if (!wdata2->cfile) {

		if (!wdata2->cfile) {

			cifs_dbg(VFS, "No writable handle to retry writepages\n");

			cifs_dbg(VFS, "No writable handle to retry writepages rc=%d\n",

				 rc);

			if (!is_retryable_error(rc))

				rc = -EBADF;

				rc = -EBADF;

		} else {

		} else {

			wdata2->pid = wdata2->cfile->pid;

			wdata2->pid = wdata2->cfile->pid;

fs/cifs/file.c

+61 −29
Original line number Original line Diff line number Diff line
@@ -1842,24 +1842,30 @@ struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode, 
	return NULL;

	return NULL;

}

}





struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,

/* Return -EBADF if no handle is found and general rc otherwise */

					bool fsuid_only)

int

cifs_get_writable_file(struct cifsInodeInfo *cifs_inode, bool fsuid_only,

		       struct cifsFileInfo **ret_file)

{

{

	struct cifsFileInfo *open_file, *inv_file = NULL;

	struct cifsFileInfo *open_file, *inv_file = NULL;

	struct cifs_sb_info *cifs_sb;

	struct cifs_sb_info *cifs_sb;

	struct cifs_tcon *tcon;

	struct cifs_tcon *tcon;

	bool any_available = false;

	bool any_available = false;

	int rc;

	int rc = -EBADF;

	unsigned int refind = 0;

	unsigned int refind = 0;





	/* Having a null inode here (because mapping->host was set to zero by

	*ret_file = NULL;

	the VFS or MM) should not happen but we had reports of on oops (due to



	it being zero) during stress testcases so we need to check for it */

	/*

	 * Having a null inode here (because mapping->host was set to zero by

	 * the VFS or MM) should not happen but we had reports of on oops (due

	 * to it being zero) during stress testcases so we need to check for it

	 */





	if (cifs_inode == NULL) {

	if (cifs_inode == NULL) {

		cifs_dbg(VFS, "Null inode passed to cifs_writeable_file\n");

		cifs_dbg(VFS, "Null inode passed to cifs_writeable_file\n");

		dump_stack();

		dump_stack();

		return NULL;

		return rc;

	}

	}





	cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);

	cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
@@ -1873,7 +1879,7 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode, 
refind_writable:

refind_writable:

	if (refind > MAX_REOPEN_ATT) {

	if (refind > MAX_REOPEN_ATT) {

		spin_unlock(&tcon->open_file_lock);

		spin_unlock(&tcon->open_file_lock);

		return NULL;

		return rc;

	}

	}

	list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {

	list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {

		if (!any_available && open_file->pid != current->tgid)

		if (!any_available && open_file->pid != current->tgid)
@@ -1885,7 +1891,8 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode, 
				/* found a good writable file */

				/* found a good writable file */

				cifsFileInfo_get(open_file);

				cifsFileInfo_get(open_file);

				spin_unlock(&tcon->open_file_lock);

				spin_unlock(&tcon->open_file_lock);

				return open_file;

				*ret_file = open_file;

				return 0;

			} else {

			} else {

				if (!inv_file)

				if (!inv_file)

					inv_file = open_file;

					inv_file = open_file;
@@ -1907,12 +1914,13 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode, 




	if (inv_file) {

	if (inv_file) {

		rc = cifs_reopen_file(inv_file, false);

		rc = cifs_reopen_file(inv_file, false);

		if (!rc)

		if (!rc) {

			return inv_file;

			*ret_file = inv_file;

		else {

			return 0;

		}



		spin_lock(&tcon->open_file_lock);

		spin_lock(&tcon->open_file_lock);

			list_move_tail(&inv_file->flist,

		list_move_tail(&inv_file->flist, &cifs_inode->openFileList);

					&cifs_inode->openFileList);

		spin_unlock(&tcon->open_file_lock);

		spin_unlock(&tcon->open_file_lock);

		cifsFileInfo_put(inv_file);

		cifsFileInfo_put(inv_file);

		++refind;

		++refind;
@@ -1920,9 +1928,21 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode, 
		spin_lock(&tcon->open_file_lock);

		spin_lock(&tcon->open_file_lock);

		goto refind_writable;

		goto refind_writable;

	}

	}



	return rc;

}

}





	return NULL;

struct cifsFileInfo *

find_writable_file(struct cifsInodeInfo *cifs_inode, bool fsuid_only)

{

	struct cifsFileInfo *cfile;

	int rc;



	rc = cifs_get_writable_file(cifs_inode, fsuid_only, &cfile);

	if (rc)

		cifs_dbg(FYI, "couldn't find writable handle rc=%d", rc);



	return cfile;

}

}





static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)

static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
@@ -1959,8 +1979,8 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to) 
	if (mapping->host->i_size - offset < (loff_t)to)

	if (mapping->host->i_size - offset < (loff_t)to)

		to = (unsigned)(mapping->host->i_size - offset);

		to = (unsigned)(mapping->host->i_size - offset);





	open_file = find_writable_file(CIFS_I(mapping->host), false);

	rc = cifs_get_writable_file(CIFS_I(mapping->host), false, &open_file);

	if (open_file) {

	if (!rc) {

		bytes_written = cifs_write(open_file, open_file->pid,

		bytes_written = cifs_write(open_file, open_file->pid,

					   write_data, to - from, &offset);

					   write_data, to - from, &offset);

		cifsFileInfo_put(open_file);

		cifsFileInfo_put(open_file);
@@ -1970,8 +1990,11 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to) 
			rc = 0;

			rc = 0;

		else if (bytes_written < 0)

		else if (bytes_written < 0)

			rc = bytes_written;

			rc = bytes_written;

		else

			rc = -EFAULT;

	} else {

	} else {

		cifs_dbg(FYI, "No writeable filehandles for inode\n");

		cifs_dbg(FYI, "No writable handle for write page rc=%d\n", rc);

		if (!is_retryable_error(rc))

			rc = -EIO;

			rc = -EIO;

	}

	}
@@ -2144,11 +2167,16 @@ static int cifs_writepages(struct address_space *mapping, 
		pgoff_t next = 0, tofind, saved_index = index;

		pgoff_t next = 0, tofind, saved_index = index;

		struct cifs_credits credits_on_stack;

		struct cifs_credits credits_on_stack;

		struct cifs_credits *credits = &credits_on_stack;

		struct cifs_credits *credits = &credits_on_stack;

		int get_file_rc = 0;





		if (cfile)

		if (cfile)

			cifsFileInfo_put(cfile);

			cifsFileInfo_put(cfile);





		cfile = find_writable_file(CIFS_I(inode), false);

		rc = cifs_get_writable_file(CIFS_I(inode), false, &cfile);



		/* in case of an error store it to return later */

		if (rc)

			get_file_rc = rc;





		rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,

		rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,

						   &wsize, credits);

						   &wsize, credits);
@@ -2189,7 +2217,11 @@ static int cifs_writepages(struct address_space *mapping, 
		cfile = NULL;

		cfile = NULL;





		if (!wdata->cfile) {

		if (!wdata->cfile) {

			cifs_dbg(VFS, "No writable handle in writepages\n");

			cifs_dbg(VFS, "No writable handle in writepages rc=%d\n",

				 get_file_rc);

			if (is_retryable_error(get_file_rc))

				rc = get_file_rc;

			else

				rc = -EBADF;

				rc = -EBADF;

		} else

		} else

			rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);

			rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);