smbd: some write time fixes
[tprouty/samba.git] / source / smbd / fileio.c
index 375bfbe..0958418 100644 (file)
@@ -7,7 +7,7 @@
    
    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 2 of the License, or
+   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,
    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, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #include "includes.h"
 
-static BOOL setup_write_cache(files_struct *, SMB_OFF_T);
+static bool setup_write_cache(files_struct *, SMB_OFF_T);
 
 /****************************************************************************
  Read from write cache if we can.
 ****************************************************************************/
 
-static BOOL read_from_write_cache(files_struct *fsp,char *data,SMB_OFF_T pos,size_t n)
+static bool read_from_write_cache(files_struct *fsp,char *data,SMB_OFF_T pos,size_t n)
 {
        write_cache *wcp = fsp->wcp;
 
@@ -78,7 +77,7 @@ ssize_t read_file(files_struct *fsp,char *data,SMB_OFF_T pos,size_t n)
 #ifdef DMF_FIX
                int numretries = 3;
 tryagain:
-               readret = SMB_VFS_PREAD(fsp,fsp->fh->fd,data,n,pos);
+               readret = SMB_VFS_PREAD(fsp,data,n,pos);
 
                if (readret == -1) {
                        if ((errno == EAGAIN) && numretries) {
@@ -90,7 +89,7 @@ tryagain:
                        return -1;
                }
 #else /* NO DMF fix. */
-               readret = SMB_VFS_PREAD(fsp,fsp->fh->fd,data,n,pos);
+               readret = SMB_VFS_PREAD(fsp,data,n,pos);
 
                if (readret == -1) {
                        return -1;
@@ -117,12 +116,16 @@ static unsigned int allocated_write_caches;
  *Really* write to a file.
 ****************************************************************************/
 
-static ssize_t real_write_file(files_struct *fsp,const char *data, SMB_OFF_T pos, size_t n)
+static ssize_t real_write_file(struct smb_request *req,
+                               files_struct *fsp,
+                               const char *data,
+                               SMB_OFF_T pos,
+                               size_t n)
 {
        ssize_t ret;
 
         if (pos == -1) {
-                ret = vfs_write_data(fsp, data, n);
+                ret = vfs_write_data(req, fsp, data, n);
         } else {
                fsp->fh->pos = pos;
                if (pos && lp_strict_allocate(SNUM(fsp->conn))) {
@@ -130,7 +133,7 @@ static ssize_t real_write_file(files_struct *fsp,const char *data, SMB_OFF_T pos
                                return -1;
                        }
                }
-                ret = vfs_pwrite_data(fsp, data, n, pos);
+                ret = vfs_pwrite_data(req, fsp, data, n, pos);
        }
 
        DEBUG(10,("real_write_file (%s): pos = %.0f, size = %lu, returned %ld\n",
@@ -139,26 +142,6 @@ static ssize_t real_write_file(files_struct *fsp,const char *data, SMB_OFF_T pos
        if (ret != -1) {
                fsp->fh->pos += ret;
 
-               /*
-                * It turns out that setting the last write time from a Windows
-                * client stops any subsequent writes from updating the write time.
-                * Doing this after the write gives a race condition here where
-                * a stat may see the changed write time before we reset it here,
-                * but it's cheaper than having to store the write time in shared
-                * memory and look it up using dev/inode across all running smbd's.
-                * The 99% solution will hopefully be good enough in this case. JRA.
-                */
-
-               if (fsp->pending_modtime) {
-                       set_filetime(fsp->conn, fsp->fsp_name, fsp->pending_modtime);
-
-                       /* If we didn't get the "set modtime" call ourselves, we must
-                          store the last write time to restore on close. JRA. */
-                       if (!fsp->pending_modtime_owner) {
-                               fsp->last_write_time = time(NULL);
-                       }
-               }
-
 /* Yes - this is correct - writes don't update this. JRA. */
 /* Found by Samba4 tests. */
 #if 0
@@ -180,7 +163,7 @@ static int wcp_file_size_change(files_struct *fsp)
        write_cache *wcp = fsp->wcp;
 
        wcp->file_size = wcp->offset + wcp->data_size;
-       ret = SMB_VFS_FTRUNCATE(fsp, fsp->fh->fd, wcp->file_size);
+       ret = SMB_VFS_FTRUNCATE(fsp, wcp->file_size);
        if (ret == -1) {
                DEBUG(0,("wcp_file_size_change (%s): ftruncate of size %.0f error %s\n",
                        fsp->fsp_name, (double)wcp->file_size, strerror(errno) ));
@@ -188,15 +171,90 @@ static int wcp_file_size_change(files_struct *fsp)
        return ret;
 }
 
+static void update_write_time_handler(struct event_context *ctx,
+                                     struct timed_event *te,
+                                     const struct timeval *now,
+                                     void *private_data)
+{
+       files_struct *fsp = (files_struct *)private_data;
+
+       /* Remove the timed event handler. */
+       TALLOC_FREE(fsp->update_write_time_event);
+       DEBUG(5, ("Update write time on %s\n", fsp->fsp_name));
+
+       /* change the write time if not already changed by someone else */
+       update_write_time(fsp);
+}
+
+/*********************************************************
+ Schedule a write time update for WRITE_TIME_UPDATE_USEC_DELAY
+ in the future.
+*********************************************************/
+
+void trigger_write_time_update(struct files_struct *fsp)
+{
+       int delay;
+
+       if (fsp->write_time_forced) {
+               /* No point - "sticky" write times
+                * in effect.
+                */
+               return;
+       }
+
+       if (fsp->update_write_time_triggered) {
+               /*
+                * No point - an event is already scheduled.
+                */
+               return;
+       }
+       fsp->update_write_time_triggered = true;
+
+       delay = lp_parm_int(SNUM(fsp->conn),
+                           "smbd", "writetimeupdatedelay",
+                           WRITE_TIME_UPDATE_USEC_DELAY);
+
+       /* trigger the update 2 seconds later */
+       fsp->update_write_time_on_close = true;
+       fsp->update_write_time_event =
+               event_add_timed(smbd_event_context(), NULL,
+                               timeval_current_ofs(0, delay),
+                               "update_write_time_handler",
+                               update_write_time_handler, fsp);
+}
+
+void trigger_write_time_update_immediate(struct files_struct *fsp)
+{
+        if (fsp->write_time_forced) {
+               /*
+                * No point - "sticky" write times
+                * in effect.
+                */
+                return;
+        }
+
+       TALLOC_FREE(fsp->update_write_time_event);
+       DEBUG(5, ("Update write time immediate on %s\n", fsp->fsp_name));
+
+       fsp->update_write_time_triggered = true;
+
+        fsp->update_write_time_on_close = false;
+       update_write_time(fsp);
+}
+
 /****************************************************************************
  Write to a file.
 ****************************************************************************/
 
-ssize_t write_file(files_struct *fsp, const char *data, SMB_OFF_T pos, size_t n)
+ssize_t write_file(struct smb_request *req,
+                       files_struct *fsp,
+                       const char *data,
+                       SMB_OFF_T pos,
+                       size_t n)
 {
        write_cache *wcp = fsp->wcp;
        ssize_t total_written = 0;
-       int write_path = -1; 
+       int write_path = -1;
 
        if (fsp->print_file) {
                fstring sharename;
@@ -214,17 +272,24 @@ ssize_t write_file(files_struct *fsp, const char *data, SMB_OFF_T pos, size_t n)
 
        if (!fsp->can_write) {
                errno = EPERM;
-               return(0);
+               return -1;
        }
 
        if (!fsp->modified) {
                SMB_STRUCT_STAT st;
                fsp->modified = True;
 
-               if (SMB_VFS_FSTAT(fsp,fsp->fh->fd,&st) == 0) {
-                       int dosmode = dos_mode(fsp->conn,fsp->fsp_name,&st);
-                       if ((lp_store_dos_attributes(SNUM(fsp->conn)) || MAP_ARCHIVE(fsp->conn)) && !IS_DOS_ARCHIVE(dosmode)) {
-                               file_set_dosmode(fsp->conn,fsp->fsp_name,dosmode | aARCH,&st, False);
+               if (SMB_VFS_FSTAT(fsp, &st) == 0) {
+                       int dosmode;
+                       trigger_write_time_update(fsp);
+                       dosmode = dos_mode(fsp->conn,fsp->fsp_name,&st);
+                       if ((lp_store_dos_attributes(SNUM(fsp->conn)) ||
+                                       MAP_ARCHIVE(fsp->conn)) &&
+                                       !IS_DOS_ARCHIVE(dosmode)) {
+                               file_set_dosmode(fsp->conn,fsp->fsp_name,
+                                               dosmode | aARCH,&st,
+                                               NULL,
+                                               false);
                        }
 
                        /*
@@ -235,8 +300,8 @@ ssize_t write_file(files_struct *fsp, const char *data, SMB_OFF_T pos, size_t n)
                        if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type) && !wcp) {
                                setup_write_cache(fsp, st.st_size);
                                wcp = fsp->wcp;
-                       } 
-               }  
+                       }
+               }
        }
 
 #ifdef WITH_PROFILE
@@ -281,9 +346,18 @@ nonop=%u allocated=%u active=%u direct=%u perfect=%u readhits=%u\n",
        }
 #endif
 
+       if (wcp && req->unread_bytes) {
+               /* If we're using receivefile don't
+                * deal with a write cache.
+                */
+               flush_write_cache(fsp, WRITE_FLUSH);
+               delete_write_cache(fsp);
+               wcp = NULL;
+       }
+
        if(!wcp) {
                DO_PROFILE_INC(writecache_direct_writes);
-               total_written = real_write_file(fsp, data, pos, n);
+               total_written = real_write_file(req, fsp, data, pos, n);
                return total_written;
        }
 
@@ -292,13 +366,13 @@ nonop=%u allocated=%u active=%u direct=%u perfect=%u readhits=%u\n",
 
        fsp->fh->pos = pos + n;
 
-       /* 
+       /*
         * If we have active cache and it isn't contiguous then we flush.
         * NOTE: There is a small problem with running out of disk ....
         */
 
        if (wcp->data_size) {
-               BOOL cache_flush_needed = False;
+               bool cache_flush_needed = False;
 
                if ((pos >= wcp->offset) && (pos <= wcp->offset + wcp->data_size)) {
       
@@ -509,15 +583,20 @@ nonop=%u allocated=%u active=%u direct=%u perfect=%u readhits=%u\n",
 
                        write_path = 3;
 
-                } else if ( (pos >= wcp->file_size) && 
+                } else if ( (pos >= wcp->file_size) &&
                            (n == 1) &&
-                           (pos < wcp->offset + 2*wcp->alloc_size) &&
-                           (wcp->file_size == wcp->offset + wcp->data_size)) {
+                           (wcp->file_size == wcp->offset + wcp->data_size) &&
+                           (pos < wcp->file_size + wcp->alloc_size)) {
 
                         /*
-                        +---------------+
-                        | Cached data   |
-                        +---------------+
+
+                End of file ---->|
+
+                 +---------------+---------------+
+                 | Cached data   | Cache buffer  |
+                 +---------------+---------------+
+
+                                 |<------- allocated size ---------------->|
 
                                                          +--------+
                                                          | 1 Byte |
@@ -525,13 +604,18 @@ nonop=%u allocated=%u active=%u direct=%u perfect=%u readhits=%u\n",
 
                        MS-Office seems to do this a lot to determine if there's enough
                        space on the filesystem to write a new file.
-                        */
 
-                       SMB_BIG_UINT new_start = wcp->offset + wcp->data_size;
+                       Change to :
+
+                End of file ---->|
+                                 +-----------------------+--------+
+                                 | Zeroed Cached data    | 1 Byte |
+                                 +-----------------------+--------+
+                        */
 
                        flush_write_cache(fsp, WRITE_FLUSH);
-                       wcp->offset = new_start;
-                       wcp->data_size = pos - new_start + 1;
+                       wcp->offset = wcp->file_size;
+                       wcp->data_size = pos - wcp->file_size + 1;
                        memset(wcp->data, '\0', wcp->data_size);
                        memcpy(wcp->data + wcp->data_size-1, data, 1);
 
@@ -601,7 +685,7 @@ len = %u\n",fsp->fh->fd, (double)pos, (unsigned int)n, (double)wcp->offset, (uns
                        if ( n <= wcp->alloc_size && n > wcp->data_size) {
                                cache_flush_needed = True;
                        } else {
-                               ssize_t ret = real_write_file(fsp, data, pos, n);
+                               ssize_t ret = real_write_file(NULL,fsp, data, pos, n);
 
                                /*
                                 * If the write overlaps the entire cache, then
@@ -648,7 +732,7 @@ n = %u, wcp->offset=%.0f, wcp->data_size=%u\n",
         */
 
        if (n > wcp->alloc_size ) {
-               ssize_t ret = real_write_file(fsp, data, pos, n);
+               ssize_t ret = real_write_file(NULL,fsp, data, pos, n);
                if (ret == -1) {
                        return -1;
                }
@@ -730,7 +814,7 @@ void delete_write_cache(files_struct *fsp)
  Setup the write cache structure.
 ****************************************************************************/
 
-static BOOL setup_write_cache(files_struct *fsp, SMB_OFF_T file_size)
+static bool setup_write_cache(files_struct *fsp, SMB_OFF_T file_size)
 {
        ssize_t alloc_size = lp_write_cache_size(SNUM(fsp->conn));
        write_cache *wcp;
@@ -780,9 +864,11 @@ void set_filelen_write_cache(files_struct *fsp, SMB_OFF_T file_size)
        if(fsp->wcp) {
                /* The cache *must* have been flushed before we do this. */
                if (fsp->wcp->data_size != 0) {
-                       pstring msg;
-                       slprintf(msg, sizeof(msg)-1, "set_filelen_write_cache: size change \
-on file %s with write cache size = %lu\n", fsp->fsp_name, (unsigned long)fsp->wcp->data_size );
+                       char *msg;
+                       asprintf(&msg, "set_filelen_write_cache: size change "
+                                "on file %s with write cache size = %lu\n",
+                                fsp->fsp_name,
+                                (unsigned long)fsp->wcp->data_size);
                        smb_panic(msg);
                }
                fsp->wcp->file_size = file_size;
@@ -817,7 +903,7 @@ ssize_t flush_write_cache(files_struct *fsp, enum flush_reason_enum reason)
        }
 #endif
 
-       ret = real_write_file(fsp, wcp->data, wcp->offset, data_size);
+       ret = real_write_file(NULL, fsp, wcp->data, wcp->offset, data_size);
 
        /*
         * Ensure file size if kept up to date if write extends file.
@@ -834,16 +920,23 @@ ssize_t flush_write_cache(files_struct *fsp, enum flush_reason_enum reason)
 sync a file
 ********************************************************************/
 
-void sync_file(connection_struct *conn, files_struct *fsp, BOOL write_through)
+NTSTATUS sync_file(connection_struct *conn, files_struct *fsp, bool write_through)
 {
                if (fsp->fh->fd == -1)
-               return;
+               return NT_STATUS_INVALID_HANDLE;
 
        if (lp_strict_sync(SNUM(conn)) &&
            (lp_syncalways(SNUM(conn)) || write_through)) {
-               flush_write_cache(fsp, SYNC_FLUSH);
-               SMB_VFS_FSYNC(fsp,fsp->fh->fd);
+               int ret = flush_write_cache(fsp, SYNC_FLUSH);
+               if (ret == -1) {
+                       return map_nt_error_from_unix(errno);
+               }
+               ret = SMB_VFS_FSYNC(fsp);
+               if (ret == -1) {
+                       return map_nt_error_from_unix(errno);
+               }
        }
+       return NT_STATUS_OK;
 }
 
 /************************************************************
@@ -855,6 +948,6 @@ int fsp_stat(files_struct *fsp, SMB_STRUCT_STAT *pst)
        if (fsp->fh->fd == -1) {
                return SMB_VFS_STAT(fsp->conn, fsp->fsp_name, pst);
        } else {
-               return SMB_VFS_FSTAT(fsp,fsp->fh->fd, pst);
+               return SMB_VFS_FSTAT(fsp, pst);
        }
 }