/* Unix SMB/CIFS implementation. IRIX kernel oplock processing Copyright (C) Andrew Tridgell 1992-1998 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/>. */ #define DBGC_CLASS DBGC_LOCKING #include "includes.h" #include "system/filesys.h" #include "smbd/smbd.h" #include "smbd/globals.h" #if HAVE_KERNEL_OPLOCKS_IRIX struct irix_oplocks_context { struct kernel_oplocks *ctx; int write_fd; int read_fd; struct fd_event *read_fde; bool pending; }; /**************************************************************************** Test to see if IRIX kernel oplocks work. ****************************************************************************/ static bool irix_oplocks_available(void) { int fd; int pfd[2]; TALLOC_CTX *ctx = talloc_stackframe(); char *tmpname = NULL; set_effective_capability(KERNEL_OPLOCK_CAPABILITY); tmpname = talloc_asprintf(ctx, "%s/koplock.%d", lp_lockdir(), (int)sys_getpid()); if (!tmpname) { TALLOC_FREE(ctx); return False; } if(pipe(pfd) != 0) { DEBUG(0,("check_kernel_oplocks: Unable to create pipe. Error " "was %s\n", strerror(errno) )); TALLOC_FREE(ctx); return False; } if((fd = sys_open(tmpname, O_RDWR|O_CREAT|O_EXCL|O_TRUNC, 0600)) < 0) { DEBUG(0,("check_kernel_oplocks: Unable to open temp test file " "%s. Error was %s\n", tmpname, strerror(errno) )); unlink( tmpname ); close(pfd[0]); close(pfd[1]); TALLOC_FREE(ctx); return False; } unlink(tmpname); TALLOC_FREE(ctx); if(sys_fcntl_long(fd, F_OPLKREG, pfd[1]) == -1) { DEBUG(0,("check_kernel_oplocks: Kernel oplocks are not " "available on this machine. Disabling kernel oplock " "support.\n" )); close(pfd[0]); close(pfd[1]); close(fd); return False; } if(sys_fcntl_long(fd, F_OPLKACK, OP_REVOKE) < 0 ) { DEBUG(0,("check_kernel_oplocks: Error when removing kernel " "oplock. Error was %s. Disabling kernel oplock " "support.\n", strerror(errno) )); close(pfd[0]); close(pfd[1]); close(fd); return False; } close(pfd[0]); close(pfd[1]); close(fd); return True; } /* * This is bad because the file_id should always be created through the vfs * layer! Unfortunately, a conn struct isn't available here. */ static struct file_id file_id_create_dev(SMB_DEV_T dev, SMB_INO_T inode) { struct file_id key; /* the ZERO_STRUCT ensures padding doesn't break using the key as a * blob */ ZERO_STRUCT(key); key.devid = dev; key.inode = inode; return key; } /**************************************************************************** * Deal with the IRIX kernel <--> smbd * oplock break protocol. ****************************************************************************/ static files_struct *irix_oplock_receive_message(struct kernel_oplocks *_ctx) { struct irix_oplocks_context *ctx = talloc_get_type(_ctx->private_data, struct irix_oplocks_context); oplock_stat_t os; char dummy; struct file_id fileid; files_struct *fsp; /* * TODO: is it correct to assume we only get one * oplock break, for each byte we read from the pipe? */ ctx->pending = false; /* * Read one byte of zero to clear the * kernel break notify message. */ if(read(ctx->read_fd, &dummy, 1) != 1) { DEBUG(0,("irix_oplock_receive_message: read of kernel " "notification failed. Error was %s.\n", strerror(errno) )); return NULL; } /* * Do a query to get the * device and inode of the file that has the break * request outstanding. */ if(sys_fcntl_ptr(ctx->read_fd, F_OPLKSTAT, &os) < 0) { DEBUG(0,("irix_oplock_receive_message: fcntl of kernel " "notification failed. Error was %s.\n", strerror(errno) )); if(errno == EAGAIN) { /* * Duplicate kernel break message - ignore. */ return NULL; } return NULL; } /* * We only have device and inode info here - we have to guess that this * is the first fsp open with this dev,ino pair. * * NOTE: this doesn't work if any VFS modules overloads * the file_id_create() hook! */ fileid = file_id_create_dev((SMB_DEV_T)os.os_dev, (SMB_INO_T)os.os_ino); if ((fsp = file_find_di_first(smbd_server_conn, fileid)) == NULL) { DEBUG(0,("irix_oplock_receive_message: unable to find open " "file with dev = %x, inode = %.0f\n", (unsigned int)os.os_dev, (double)os.os_ino )); return NULL; } DEBUG(5,("irix_oplock_receive_message: kernel oplock break request " "received for file_id %s gen_id = %ul", file_id_string_tos(&fsp->file_id), fsp->fh->gen_id )); return fsp; } /**************************************************************************** Attempt to set an kernel oplock on a file. ****************************************************************************/ static bool irix_set_kernel_oplock(struct kernel_oplocks *_ctx, files_struct *fsp, int oplock_type) { struct irix_oplocks_context *ctx = talloc_get_type(_ctx->private_data, struct irix_oplocks_context); if (sys_fcntl_long(fsp->fh->fd, F_OPLKREG, ctx->write_fd) == -1) { if(errno != EAGAIN) { DEBUG(0,("irix_set_kernel_oplock: Unable to get " "kernel oplock on file %s, file_id %s " "gen_id = %ul. Error was %s\n", fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id), fsp->fh->gen_id, strerror(errno) )); } else { DEBUG(5,("irix_set_kernel_oplock: Refused oplock on " "file %s, fd = %d, file_id = %s, " "gen_id = %ul. Another process had the file " "open.\n", fsp_str_dbg(fsp), fsp->fh->fd, file_id_string_tos(&fsp->file_id), fsp->fh->gen_id )); } return False; } DEBUG(10,("irix_set_kernel_oplock: got kernel oplock on file %s, file_id = %s " "gen_id = %ul\n", fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id), fsp->fh->gen_id)); return True; } /**************************************************************************** Release a kernel oplock on a file. ****************************************************************************/ static void irix_release_kernel_oplock(struct kernel_oplocks *_ctx, files_struct *fsp, int oplock_type) { if (DEBUGLVL(10)) { /* * Check and print out the current kernel * oplock state of this file. */ int state = sys_fcntl_long(fsp->fh->fd, F_OPLKACK, -1); dbgtext("irix_release_kernel_oplock: file %s, file_id = %s" "gen_id = %ul, has kernel oplock state " "of %x.\n", fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id), fsp->fh->gen_id, state ); } /* * Remove the kernel oplock on this file. */ if(sys_fcntl_long(fsp->fh->fd, F_OPLKACK, OP_REVOKE) < 0) { if( DEBUGLVL( 0 )) { dbgtext("irix_release_kernel_oplock: Error when " "removing kernel oplock on file " ); dbgtext("%s, file_id = %s gen_id = %ul. " "Error was %s\n", fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id), fsp->fh->gen_id, strerror(errno) ); } } } static void irix_oplocks_read_fde_handler(struct event_context *ev, struct fd_event *fde, uint16_t flags, void *private_data) { struct irix_oplocks_context *ctx = talloc_get_type(private_data, struct irix_oplocks_context); files_struct *fsp; fsp = irix_oplock_receive_message(ctx->ctx); break_kernel_oplock(fsp->conn->sconn->msg_ctx, fsp); } /**************************************************************************** Setup kernel oplocks. ****************************************************************************/ static const struct kernel_oplocks_ops irix_koplocks = { .set_oplock = irix_set_kernel_oplock, .release_oplock = irix_release_kernel_oplock, .contend_level2_oplocks_begin = NULL, .contend_level2_oplocks_end = NULL, }; struct kernel_oplocks *irix_init_kernel_oplocks(TALLOC_CTX *mem_ctx) { struct kernel_oplocks *_ctx; struct irix_oplocks_context *ctx; int pfd[2]; if (!irix_oplocks_available()) return NULL; _ctx = talloc_zero(mem_ctx, struct kernel_oplocks); if (!_ctx) { return NULL; } ctx = talloc_zero(_ctx, struct irix_oplocks_context); if (!ctx) { talloc_free(_ctx); return NULL; } _ctx->ops = &irix_koplocks; _ctx->private_data = ctx; ctx->ctx = _ctx; if(pipe(pfd) != 0) { talloc_free(_ctx); DEBUG(0,("setup_kernel_oplock_pipe: Unable to create pipe. " "Error was %s\n", strerror(errno) )); return False; } ctx->read_fd = pfd[0]; ctx->write_fd = pfd[1]; ctx->read_fde = event_add_fd(server_event_context(), ctx, ctx->read_fd, EVENT_FD_READ, irix_oplocks_read_fde_handler, ctx); return _ctx; } #else void oplock_irix_dummy(void); void oplock_irix_dummy(void) {} #endif /* HAVE_KERNEL_OPLOCKS_IRIX */