From 8daa83a594a2e98f39d764422bfbdbc62c9efd44 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 19:20:00 +0200 Subject: Adding upstream version 2:4.20.0+dfsg. Signed-off-by: Daniel Baumann --- source3/modules/vfs_readahead.c | 186 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 source3/modules/vfs_readahead.c (limited to 'source3/modules/vfs_readahead.c') diff --git a/source3/modules/vfs_readahead.c b/source3/modules/vfs_readahead.c new file mode 100644 index 0000000..bb31b57 --- /dev/null +++ b/source3/modules/vfs_readahead.c @@ -0,0 +1,186 @@ +/* + * Copyright (c) Jeremy Allison 2007. + * + * 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 . + */ + +#include "includes.h" +#include "system/filesys.h" +#include "smbd/smbd.h" + +#if defined(HAVE_LINUX_READAHEAD) && ! defined(HAVE_READAHEAD_DECL) +ssize_t readahead(int fd, off_t offset, size_t count); +#endif + +struct readahead_data { + off_t off_bound; + off_t len; + bool didmsg; +}; + +/* + * This module copes with Vista AIO read requests on Linux + * by detecting the initial 0x80000 boundary reads and causing + * the buffer cache to be filled in advance. + */ + +/******************************************************************* + sendfile wrapper that does readahead/posix_fadvise. +*******************************************************************/ + +static ssize_t readahead_sendfile(struct vfs_handle_struct *handle, + int tofd, + files_struct *fromfsp, + const DATA_BLOB *header, + off_t offset, + size_t count) +{ + struct readahead_data *rhd = (struct readahead_data *)handle->data; + + if ( offset % rhd->off_bound == 0) { +#if defined(HAVE_LINUX_READAHEAD) + int err = readahead(fsp_get_io_fd(fromfsp), offset, (size_t)rhd->len); + DEBUG(10,("readahead_sendfile: readahead on fd %u, offset %llu, len %u returned %d\n", + (unsigned int)fsp_get_io_fd(fromfsp), + (unsigned long long)offset, + (unsigned int)rhd->len, + err )); +#elif defined(HAVE_POSIX_FADVISE) + int err = posix_fadvise(fsp_get_io_fd(fromfsp), offset, (off_t)rhd->len, POSIX_FADV_WILLNEED); + DEBUG(10,("readahead_sendfile: posix_fadvise on fd %u, offset %llu, len %u returned %d\n", + (unsigned int)fsp_get_io_fd(fromfsp), + (unsigned long long)offset, + (unsigned int)rhd->len, + err )); +#else + if (!rhd->didmsg) { + DEBUG(0,("readahead_sendfile: no readahead on this platform\n")); + rhd->didmsg = True; + } +#endif + } + return SMB_VFS_NEXT_SENDFILE(handle, + tofd, + fromfsp, + header, + offset, + count); +} + +/******************************************************************* + pread wrapper that does readahead/posix_fadvise. +*******************************************************************/ + +static ssize_t readahead_pread(vfs_handle_struct *handle, + files_struct *fsp, + void *data, + size_t count, + off_t offset) +{ + struct readahead_data *rhd = (struct readahead_data *)handle->data; + + if ( offset % rhd->off_bound == 0) { +#if defined(HAVE_LINUX_READAHEAD) + int err = readahead(fsp_get_io_fd(fsp), offset, (size_t)rhd->len); + DEBUG(10,("readahead_pread: readahead on fd %u, offset %llu, len %u returned %d\n", + (unsigned int)fsp_get_io_fd(fsp), + (unsigned long long)offset, + (unsigned int)rhd->len, + err )); +#elif defined(HAVE_POSIX_FADVISE) + int err = posix_fadvise(fsp_get_io_fd(fsp), offset, (off_t)rhd->len, POSIX_FADV_WILLNEED); + DEBUG(10,("readahead_pread: posix_fadvise on fd %u, offset %llu, len %u returned %d\n", + (unsigned int)fsp_get_io_fd(fsp), + (unsigned long long)offset, + (unsigned int)rhd->len, + err )); +#else + if (!rhd->didmsg) { + DEBUG(0,("readahead_pread: no readahead on this platform\n")); + rhd->didmsg = True; + } +#endif + } + return SMB_VFS_NEXT_PREAD(handle, fsp, data, count, offset); +} + +/******************************************************************* + Directly called from main smbd when freeing handle. +*******************************************************************/ + +static void free_readahead_data(void **pptr) +{ + SAFE_FREE(*pptr); +} + +/******************************************************************* + Allocate the handle specific data so we don't call the expensive + conv_str_size function for each sendfile/pread. +*******************************************************************/ + +static int readahead_connect(struct vfs_handle_struct *handle, + const char *service, + const char *user) +{ + struct readahead_data *rhd; + int ret = SMB_VFS_NEXT_CONNECT(handle, service, user); + + if (ret < 0) { + return ret; + } + rhd = SMB_MALLOC_P(struct readahead_data); + if (!rhd) { + SMB_VFS_NEXT_DISCONNECT(handle); + DEBUG(0,("readahead_connect: out of memory\n")); + return -1; + } + ZERO_STRUCTP(rhd); + + rhd->didmsg = False; + rhd->off_bound = conv_str_size(lp_parm_const_string(SNUM(handle->conn), + "readahead", + "offset", + NULL)); + if (rhd->off_bound == 0) { + rhd->off_bound = 0x80000; + } + rhd->len = conv_str_size(lp_parm_const_string(SNUM(handle->conn), + "readahead", + "length", + NULL)); + if (rhd->len == 0) { + rhd->len = rhd->off_bound; + } + + handle->data = (void *)rhd; + handle->free_data = free_readahead_data; + return 0; +} + +static struct vfs_fn_pointers vfs_readahead_fns = { + .sendfile_fn = readahead_sendfile, + .pread_fn = readahead_pread, + .connect_fn = readahead_connect +}; + +/******************************************************************* + Module initialization boilerplate. +*******************************************************************/ + +static_decl_vfs; +NTSTATUS vfs_readahead_init(TALLOC_CTX *ctx) +{ + return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "readahead", + &vfs_readahead_fns); +} -- cgit v1.2.3