1
0
mirror of https://github.com/samba-team/samba.git synced 2024-12-22 13:34:15 +03:00
samba-mirror/source3/modules/vfs_btrfs.c
David Disseldorp 3be664969d vfs_btrfs: pass-through copy-chunk(len=0) requests
Never map copy-chunk(len=0) requests to BTRFS_IOC_CLONE_RANGE ioctls. A
BTRFS_IOC_CLONE_RANGE with @src_length=0 results in a clone of all data
from @src_offset->EOF!

BUG: https://bugzilla.samba.org/show_bug.cgi?id=10424

Signed-off-by: David Disseldorp <ddiss@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
2014-02-06 16:15:29 -08:00

350 lines
9.4 KiB
C

/*
* Module to make use of awesome Btrfs features
*
* Copyright (C) David Disseldorp 2011-2013
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/ioctl.h>
#include <linux/fs.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <fcntl.h>
#include "system/filesys.h"
#include "includes.h"
#include "smbd/smbd.h"
#include "librpc/gen_ndr/smbXsrv.h"
#include "librpc/gen_ndr/ioctl.h"
#include "lib/util/tevent_ntstatus.h"
static uint32_t btrfs_fs_capabilities(struct vfs_handle_struct *handle,
enum timestamp_set_resolution *_ts_res)
{
uint32_t fs_capabilities;
enum timestamp_set_resolution ts_res;
/* inherit default capabilities, expose compression support */
fs_capabilities = SMB_VFS_NEXT_FS_CAPABILITIES(handle, &ts_res);
fs_capabilities |= FILE_FILE_COMPRESSION;
*_ts_res = ts_res;
return fs_capabilities;
}
struct btrfs_ioctl_clone_range_args {
int64_t src_fd;
uint64_t src_offset;
uint64_t src_length;
uint64_t dest_offset;
};
#define BTRFS_IOCTL_MAGIC 0x94
#define BTRFS_IOC_CLONE_RANGE _IOW(BTRFS_IOCTL_MAGIC, 13, \
struct btrfs_ioctl_clone_range_args)
struct btrfs_cc_state {
struct vfs_handle_struct *handle;
off_t copied;
struct tevent_req *subreq; /* non-null if passed to next VFS fn */
};
static void btrfs_copy_chunk_done(struct tevent_req *subreq);
static struct tevent_req *btrfs_copy_chunk_send(struct vfs_handle_struct *handle,
TALLOC_CTX *mem_ctx,
struct tevent_context *ev,
struct files_struct *src_fsp,
off_t src_off,
struct files_struct *dest_fsp,
off_t dest_off,
off_t num)
{
struct tevent_req *req;
struct btrfs_cc_state *cc_state;
struct btrfs_ioctl_clone_range_args cr_args;
struct lock_struct src_lck;
struct lock_struct dest_lck;
int ret;
NTSTATUS status;
req = tevent_req_create(mem_ctx, &cc_state, struct btrfs_cc_state);
if (req == NULL) {
return NULL;
}
cc_state->handle = handle;
if (num == 0) {
/*
* With a @src_length of zero, BTRFS_IOC_CLONE_RANGE clones
* all data from @src_offset->EOF! This is certainly not what
* the caller expects, and not what vfs_default does.
*/
cc_state->subreq = SMB_VFS_NEXT_COPY_CHUNK_SEND(handle,
cc_state, ev,
src_fsp,
src_off,
dest_fsp,
dest_off, num);
if (tevent_req_nomem(cc_state->subreq, req)) {
return tevent_req_post(req, ev);
}
tevent_req_set_callback(cc_state->subreq,
btrfs_copy_chunk_done,
req);
return req;
}
status = vfs_stat_fsp(src_fsp);
if (tevent_req_nterror(req, status)) {
return tevent_req_post(req, ev);
}
if (src_fsp->fsp_name->st.st_ex_size < src_off + num) {
/* [MS-SMB2] Handling a Server-Side Data Copy Request */
tevent_req_nterror(req, NT_STATUS_INVALID_VIEW_SIZE);
return tevent_req_post(req, ev);
}
init_strict_lock_struct(src_fsp,
src_fsp->op->global->open_persistent_id,
src_off,
num,
READ_LOCK,
&src_lck);
init_strict_lock_struct(dest_fsp,
dest_fsp->op->global->open_persistent_id,
dest_off,
num,
WRITE_LOCK,
&dest_lck);
if (!SMB_VFS_STRICT_LOCK(src_fsp->conn, src_fsp, &src_lck)) {
tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
return tevent_req_post(req, ev);
}
if (!SMB_VFS_STRICT_LOCK(dest_fsp->conn, dest_fsp, &dest_lck)) {
SMB_VFS_STRICT_UNLOCK(src_fsp->conn, src_fsp, &src_lck);
tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
return tevent_req_post(req, ev);
}
ZERO_STRUCT(cr_args);
cr_args.src_fd = src_fsp->fh->fd;
cr_args.src_offset = (uint64_t)src_off;
cr_args.dest_offset = (uint64_t)dest_off;
cr_args.src_length = (uint64_t)num;
ret = ioctl(dest_fsp->fh->fd, BTRFS_IOC_CLONE_RANGE, &cr_args);
SMB_VFS_STRICT_UNLOCK(dest_fsp->conn, dest_fsp, &dest_lck);
SMB_VFS_STRICT_UNLOCK(src_fsp->conn, src_fsp, &src_lck);
if (ret < 0) {
/*
* BTRFS_IOC_CLONE_RANGE only supports 'sectorsize' aligned
* cloning. Which is 4096 by default, therefore fall back to
* manual read/write on failure.
*/
DEBUG(5, ("BTRFS_IOC_CLONE_RANGE failed: %s, length %llu, "
"src fd: %lld off: %llu, dest fd: %d off: %llu\n",
strerror(errno),
(unsigned long long)cr_args.src_length,
(long long)cr_args.src_fd,
(unsigned long long)cr_args.src_offset,
dest_fsp->fh->fd,
(unsigned long long)cr_args.dest_offset));
cc_state->subreq = SMB_VFS_NEXT_COPY_CHUNK_SEND(handle,
cc_state, ev,
src_fsp,
src_off,
dest_fsp,
dest_off, num);
if (tevent_req_nomem(cc_state->subreq, req)) {
return tevent_req_post(req, ev);
}
/* wait for subreq completion */
tevent_req_set_callback(cc_state->subreq,
btrfs_copy_chunk_done,
req);
return req;
}
DEBUG(5, ("BTRFS_IOC_CLONE_RANGE returned %d\n", ret));
/* BTRFS_IOC_CLONE_RANGE is all or nothing */
cc_state->copied = num;
tevent_req_done(req);
return tevent_req_post(req, ev);
}
/* only used if the request is passed through to next VFS module */
static void btrfs_copy_chunk_done(struct tevent_req *subreq)
{
struct tevent_req *req = tevent_req_callback_data(
subreq, struct tevent_req);
struct btrfs_cc_state *cc_state = tevent_req_data(req,
struct btrfs_cc_state);
NTSTATUS status;
status = SMB_VFS_NEXT_COPY_CHUNK_RECV(cc_state->handle,
cc_state->subreq,
&cc_state->copied);
if (tevent_req_nterror(req, status)) {
return;
}
tevent_req_done(req);
}
static NTSTATUS btrfs_copy_chunk_recv(struct vfs_handle_struct *handle,
struct tevent_req *req,
off_t *copied)
{
NTSTATUS status;
struct btrfs_cc_state *cc_state = tevent_req_data(req,
struct btrfs_cc_state);
if (tevent_req_is_nterror(req, &status)) {
DEBUG(4, ("server side copy chunk failed: %s\n",
nt_errstr(status)));
tevent_req_received(req);
return status;
}
DEBUG(10, ("server side copy chunk copied %llu\n",
(unsigned long long)cc_state->copied));
*copied = cc_state->copied;
tevent_req_received(req);
return NT_STATUS_OK;
}
/*
* caller must pass a non-null fsp or smb_fname. If fsp is null, then
* fall back to opening the corresponding file to issue the ioctl.
*/
static NTSTATUS btrfs_get_compression(struct vfs_handle_struct *handle,
TALLOC_CTX *mem_ctx,
struct files_struct *fsp,
struct smb_filename *smb_fname,
uint16_t *_compression_fmt)
{
int ret;
long flags = 0;
int fd;
bool opened = false;
NTSTATUS status;
if ((fsp != NULL) && (fsp->fh->fd != -1)) {
fd = fsp->fh->fd;
} else if (smb_fname != NULL) {
if (S_ISDIR(smb_fname->st.st_ex_mode)) {
DIR *dir = opendir(smb_fname->base_name);
if (dir == NULL) {
return NT_STATUS_UNSUCCESSFUL;
}
fd = dirfd(dir);
} else {
fd = open(smb_fname->base_name, O_RDONLY);
}
if (fd < 0) {
return NT_STATUS_UNSUCCESSFUL;
}
opened = true;
} else {
return NT_STATUS_INVALID_PARAMETER;
}
ret = ioctl(fd, FS_IOC_GETFLAGS, &flags);
if (ret < 0) {
DEBUG(1, ("FS_IOC_GETFLAGS failed: %s, fd %lld\n",
strerror(errno), (long long)fd));
status = map_nt_error_from_unix(errno);
goto err_close;
}
if (flags & FS_COMPR_FL) {
*_compression_fmt = COMPRESSION_FORMAT_LZNT1;
} else {
*_compression_fmt = COMPRESSION_FORMAT_NONE;
}
status = NT_STATUS_OK;
err_close:
if (opened) {
close(fd);
}
return status;
}
static NTSTATUS btrfs_set_compression(struct vfs_handle_struct *handle,
TALLOC_CTX *mem_ctx,
struct files_struct *fsp,
uint16_t compression_fmt)
{
int ret;
long flags = 0;
int fd;
NTSTATUS status;
if ((fsp == NULL) || (fsp->fh->fd == -1)) {
status = NT_STATUS_INVALID_PARAMETER;
goto err_out;
}
fd = fsp->fh->fd;
ret = ioctl(fd, FS_IOC_GETFLAGS, &flags);
if (ret < 0) {
DEBUG(1, ("FS_IOC_GETFLAGS failed: %s, fd %d\n",
strerror(errno), fd));
status = map_nt_error_from_unix(errno);
goto err_out;
}
if (compression_fmt == COMPRESSION_FORMAT_NONE) {
DEBUG(5, ("setting compression\n"));
flags &= (~FS_COMPR_FL);
} else if ((compression_fmt == COMPRESSION_FORMAT_DEFAULT)
|| (compression_fmt == COMPRESSION_FORMAT_LZNT1)) {
DEBUG(5, ("clearing compression\n"));
flags |= FS_COMPR_FL;
} else {
DEBUG(1, ("invalid compression format 0x%x\n",
(int)compression_fmt));
status = NT_STATUS_INVALID_PARAMETER;
goto err_out;
}
ret = ioctl(fd, FS_IOC_SETFLAGS, &flags);
if (ret < 0) {
DEBUG(1, ("FS_IOC_SETFLAGS failed: %s, fd %d\n",
strerror(errno), fd));
status = map_nt_error_from_unix(errno);
goto err_out;
}
status = NT_STATUS_OK;
err_out:
return status;
}
static struct vfs_fn_pointers btrfs_fns = {
.fs_capabilities_fn = btrfs_fs_capabilities,
.copy_chunk_send_fn = btrfs_copy_chunk_send,
.copy_chunk_recv_fn = btrfs_copy_chunk_recv,
.get_compression_fn = btrfs_get_compression,
.set_compression_fn = btrfs_set_compression,
};
NTSTATUS vfs_btrfs_init(void);
NTSTATUS vfs_btrfs_init(void)
{
return smb_register_vfs(SMB_VFS_INTERFACE_VERSION,
"btrfs", &btrfs_fns);
}