diff options
Diffstat (limited to 'source/locking/shmem.c')
| -rw-r--r-- | source/locking/shmem.c | 531 |
1 files changed, 274 insertions, 257 deletions
diff --git a/source/locking/shmem.c b/source/locking/shmem.c index 1f9cb8b7327..72d7c07751b 100644 --- a/source/locking/shmem.c +++ b/source/locking/shmem.c @@ -152,6 +152,136 @@ static BOOL smb_shm_global_unlock(void) } + +static void *smb_shm_offset2addr(int offset) +{ + if (offset == NULL_OFFSET ) + return (void *)(0); + + if (!smb_shm_header_p) + return (void *)(0); + + return (void *)((char *)smb_shm_header_p + offset ); +} + +static int smb_shm_addr2offset(void *addr) +{ + if (!addr) + return NULL_OFFSET; + + if (!smb_shm_header_p) + return NULL_OFFSET; + + return (int)((char *)addr - (char *)smb_shm_header_p); +} + + + +static int smb_shm_alloc(int size) +{ + unsigned num_cells ; + struct SmbShmBlockDesc *scanner_p; + struct SmbShmBlockDesc *prev_p; + struct SmbShmBlockDesc *new_p; + int result_offset; + + + if( !smb_shm_header_p ) + { + /* not mapped yet */ + DEBUG(0,("ERROR smb_shm_alloc : shmem not mapped\n")); + return NULL_OFFSET; + } + + smb_shm_global_lock(); + + if( !smb_shm_header_p->consistent) + { + DEBUG(0,("ERROR smb_shm_alloc : shmem not consistent\n")); + smb_shm_global_unlock(); + return NULL_OFFSET; + } + + + /* calculate the number of cells */ + num_cells = (size + CellSize -1) / CellSize; + + /* set start of scan */ + prev_p = (struct SmbShmBlockDesc *)smb_shm_offset2addr(smb_shm_header_p->first_free_off); + scanner_p = prev_p ; + + /* scan the free list to find a matching free space */ + while ( ( scanner_p != EOList_Addr ) && ( scanner_p->size < num_cells ) ) + { + prev_p = scanner_p; + scanner_p = (struct SmbShmBlockDesc *)smb_shm_offset2addr(scanner_p->next); + } + + /* at this point scanner point to a block header or to the end of the list */ + if ( scanner_p == EOList_Addr ) + { + DEBUG(0,("ERROR smb_shm_alloc : alloc of %d bytes failed, no free space found\n",size)); + smb_shm_global_unlock(); + return (NULL_OFFSET); + } + + /* going to modify shared mem */ + smb_shm_header_p->consistent = False; + + /* if we found a good one : scanner == the good one */ + if ( scanner_p->size <= num_cells + 2 ) + { + /* there is no use in making a new one, it will be too small anyway + * we will link out scanner + */ + if ( prev_p == scanner_p ) + { + smb_shm_header_p->first_free_off = scanner_p->next ; + } + else + { + prev_p->next = scanner_p->next ; + } + smb_shm_header_p->statistics.cells_free -= scanner_p->size; + smb_shm_header_p->statistics.cells_used += scanner_p->size; + } + else + { + /* Make a new one */ + new_p = scanner_p + 1 + num_cells; + new_p->size = scanner_p->size - num_cells - 1; + new_p->next = scanner_p->next; + scanner_p->size = num_cells; + scanner_p->next = smb_shm_addr2offset(new_p); + + if ( prev_p != scanner_p ) + { + prev_p->next = smb_shm_addr2offset(new_p) ; + } + else + { + smb_shm_header_p->first_free_off = smb_shm_addr2offset(new_p) ; + } + smb_shm_header_p->statistics.cells_free -= num_cells+1; + smb_shm_header_p->statistics.cells_used += num_cells; + smb_shm_header_p->statistics.cells_system += 1; + } + + result_offset = smb_shm_addr2offset( &(scanner_p[1]) ); + scanner_p->next = SMB_SHM_NOT_FREE_OFF ; + + /* end modification of shared mem */ + smb_shm_header_p->consistent = True; + + DEBUG(6,("smb_shm_alloc : request for %d bytes, allocated %d bytes at offset %d\n",size,scanner_p->size*CellSize,result_offset )); + + smb_shm_global_unlock(); + return ( result_offset ); +} + + + + /* * Function to create the hash table for the share mode entries. Called * when smb shared memory is global locked. @@ -391,130 +521,7 @@ static void smb_shm_solve_neighbors(struct SmbShmBlockDesc *head_p ) -BOOL smb_shm_open(char *file_name, int size, int ronly) -{ - int filesize; - BOOL created_new = False; - BOOL other_processes = True; - - read_only = ronly; - - DEBUG(5,("smb_shm_open : using shmem file %s to be of size %d\n",file_name,size)); - - smb_shm_fd = open(file_name, read_only?O_RDONLY:(O_RDWR|O_CREAT), - SHM_FILE_MODE); - - if ( smb_shm_fd < 0 ) - { - DEBUG(0,("ERROR smb_shm_open : open failed with code %s\n",strerror(errno))); - return False; - } - - if (!smb_shm_global_lock()) - { - DEBUG(0,("ERROR smb_shm_open : can't do smb_shm_global_lock\n")); - return False; - } - - if( (filesize = lseek(smb_shm_fd, 0, SEEK_END)) < 0) - { - DEBUG(0,("ERROR smb_shm_open : lseek failed with code %s\n",strerror(errno))); - smb_shm_global_unlock(); - close(smb_shm_fd); - return False; - } - - /* return the file offset to 0 to save on later seeks */ - lseek(smb_shm_fd,0,SEEK_SET); - - if (filesize == 0) - { - /* we just created a new one */ - created_new = True; - } - - /* to find out if some other process is already mapping the file, - we use a registration file containing the processids of the file mapping processes - */ - - /* construct processreg file name */ - strcpy(smb_shm_processreg_name, file_name); - strcat(smb_shm_processreg_name, ".processes"); - - if (!read_only && - !smb_shm_register_process(smb_shm_processreg_name, getpid(), &other_processes)) - { - smb_shm_global_unlock(); - close(smb_shm_fd); - return False; - } - - if (!read_only && (created_new || !other_processes)) - { - /* we just created a new one, or are the first opener, lets set it size */ - if( ftruncate(smb_shm_fd, size) <0) - { - DEBUG(0,("ERROR smb_shm_open : ftruncate failed with code %s\n",strerror(errno))); - smb_shm_unregister_process(smb_shm_processreg_name, getpid()); - smb_shm_global_unlock(); - close(smb_shm_fd); - return False; - } - - /* paranoia */ - lseek(smb_shm_fd,0,SEEK_SET); - - filesize = size; - } - - if (size != filesize ) - { - /* the existing file has a different size and we are not the first opener. - Since another process is still using it, we will use the file size */ - DEBUG(0,("WARNING smb_shm_open : filesize (%d) != expected size (%d), using filesize\n",filesize,size)); - size = filesize; - } - - smb_shm_header_p = (struct SmbShmHeader *)mmap(NULL, size, - read_only?PROT_READ: - (PROT_READ | PROT_WRITE), - MAP_FILE | MAP_SHARED, - smb_shm_fd, 0); - /* WARNING, smb_shm_header_p can be different for different processes mapping the same file ! */ - if (smb_shm_header_p == (struct SmbShmHeader *)(-1)) - { - DEBUG(0,("ERROR smb_shm_open : mmap failed with code %s\n",strerror(errno))); - smb_shm_unregister_process(smb_shm_processreg_name, getpid()); - smb_shm_global_unlock(); - close(smb_shm_fd); - return False; - } - - - if (!read_only && (created_new || !other_processes)) - { - smb_shm_initialize(size); - /* Create the hash buckets for the share file entries. */ - smb_shm_create_hash_table( lp_shmem_hash_size() ); - } - else if (!smb_shm_validate_header(size) ) - { - /* existing file is corrupt, samba admin should remove it by hand */ - DEBUG(0,("ERROR smb_shm_open : corrupt shared mem file, remove it manually\n")); - munmap((caddr_t)smb_shm_header_p, size); - smb_shm_unregister_process(smb_shm_processreg_name, getpid()); - smb_shm_global_unlock(); - close(smb_shm_fd); - return False; - } - - smb_shm_global_unlock(); - return True; - -} - - -BOOL smb_shm_close( void ) +static BOOL smb_shm_close( void ) { if(smb_shm_initialize_called == False) @@ -545,111 +552,8 @@ BOOL smb_shm_close( void ) return True; } -int smb_shm_alloc(int size) -{ - unsigned num_cells ; - struct SmbShmBlockDesc *scanner_p; - struct SmbShmBlockDesc *prev_p; - struct SmbShmBlockDesc *new_p; - int result_offset; - - - if( !smb_shm_header_p ) - { - /* not mapped yet */ - DEBUG(0,("ERROR smb_shm_alloc : shmem not mapped\n")); - return NULL_OFFSET; - } - - smb_shm_global_lock(); - if( !smb_shm_header_p->consistent) - { - DEBUG(0,("ERROR smb_shm_alloc : shmem not consistent\n")); - smb_shm_global_unlock(); - return NULL_OFFSET; - } - - - /* calculate the number of cells */ - num_cells = (size + CellSize -1) / CellSize; - - /* set start of scan */ - prev_p = (struct SmbShmBlockDesc *)smb_shm_offset2addr(smb_shm_header_p->first_free_off); - scanner_p = prev_p ; - - /* scan the free list to find a matching free space */ - while ( ( scanner_p != EOList_Addr ) && ( scanner_p->size < num_cells ) ) - { - prev_p = scanner_p; - scanner_p = (struct SmbShmBlockDesc *)smb_shm_offset2addr(scanner_p->next); - } - - /* at this point scanner point to a block header or to the end of the list */ - if ( scanner_p == EOList_Addr ) - { - DEBUG(0,("ERROR smb_shm_alloc : alloc of %d bytes failed, no free space found\n",size)); - smb_shm_global_unlock(); - return (NULL_OFFSET); - } - - /* going to modify shared mem */ - smb_shm_header_p->consistent = False; - - /* if we found a good one : scanner == the good one */ - if ( scanner_p->size <= num_cells + 2 ) - { - /* there is no use in making a new one, it will be too small anyway - * we will link out scanner - */ - if ( prev_p == scanner_p ) - { - smb_shm_header_p->first_free_off = scanner_p->next ; - } - else - { - prev_p->next = scanner_p->next ; - } - smb_shm_header_p->statistics.cells_free -= scanner_p->size; - smb_shm_header_p->statistics.cells_used += scanner_p->size; - } - else - { - /* Make a new one */ - new_p = scanner_p + 1 + num_cells; - new_p->size = scanner_p->size - num_cells - 1; - new_p->next = scanner_p->next; - scanner_p->size = num_cells; - scanner_p->next = smb_shm_addr2offset(new_p); - - if ( prev_p != scanner_p ) - { - prev_p->next = smb_shm_addr2offset(new_p) ; - } - else - { - smb_shm_header_p->first_free_off = smb_shm_addr2offset(new_p) ; - } - smb_shm_header_p->statistics.cells_free -= num_cells+1; - smb_shm_header_p->statistics.cells_used += num_cells; - smb_shm_header_p->statistics.cells_system += 1; - } - - result_offset = smb_shm_addr2offset( &(scanner_p[1]) ); - scanner_p->next = SMB_SHM_NOT_FREE_OFF ; - - /* end modification of shared mem */ - smb_shm_header_p->consistent = True; - - DEBUG(6,("smb_shm_alloc : request for %d bytes, allocated %d bytes at offset %d\n",size,scanner_p->size*CellSize,result_offset )); - - smb_shm_global_unlock(); - return ( result_offset ); -} - - - -BOOL smb_shm_free(int offset) +static BOOL smb_shm_free(int offset) { struct SmbShmBlockDesc *header_p ; /* pointer to header of block to free */ struct SmbShmBlockDesc *scanner_p ; /* used to scan the list */ @@ -728,7 +632,7 @@ BOOL smb_shm_free(int offset) } } -int smb_shm_get_userdef_off(void) +static int smb_shm_get_userdef_off(void) { if (!smb_shm_header_p) return NULL_OFFSET; @@ -736,33 +640,10 @@ int smb_shm_get_userdef_off(void) return smb_shm_header_p->userdef_off; } -void *smb_shm_offset2addr(int offset) -{ - if (offset == NULL_OFFSET ) - return (void *)(0); - - if (!smb_shm_header_p) - return (void *)(0); - - return (void *)((char *)smb_shm_header_p + offset ); -} - -int smb_shm_addr2offset(void *addr) -{ - if (!addr) - return NULL_OFFSET; - - if (!smb_shm_header_p) - return NULL_OFFSET; - - return (int)((char *)addr - (char *)smb_shm_header_p); -} - /******************************************************************* Lock a particular hash bucket entry. ******************************************************************/ - -BOOL smb_shm_lock_hash_entry( unsigned int entry) +static BOOL smb_shm_lock_hash_entry( unsigned int entry) { int start = (smb_shm_header_p->userdef_off + (entry * sizeof(int))); @@ -792,8 +673,7 @@ BOOL smb_shm_lock_hash_entry( unsigned int entry) /******************************************************************* Unlock a particular hash bucket entry. ******************************************************************/ - -BOOL smb_shm_unlock_hash_entry( unsigned int entry ) +static BOOL smb_shm_unlock_hash_entry( unsigned int entry ) { int start = (smb_shm_header_p->userdef_off + (entry * sizeof(int))); @@ -823,8 +703,7 @@ BOOL smb_shm_unlock_hash_entry( unsigned int entry ) /******************************************************************* Gather statistics on shared memory usage. ******************************************************************/ - -BOOL smb_shm_get_usage(int *bytes_free, +static BOOL smb_shm_get_usage(int *bytes_free, int *bytes_used, int *bytes_overhead) { @@ -841,6 +720,144 @@ BOOL smb_shm_get_usage(int *bytes_free, return True; } + +static struct shmem_ops shmops = { + smb_shm_close, + smb_shm_alloc, + smb_shm_free, + smb_shm_get_userdef_off, + smb_shm_offset2addr, + smb_shm_addr2offset, + smb_shm_lock_hash_entry, + smb_shm_unlock_hash_entry, + smb_shm_get_usage, +}; + +/******************************************************************* + open the shared memory + ******************************************************************/ +struct shmem_ops *smb_shm_open(char *file_name, int size, int ronly) +{ + int filesize; + BOOL created_new = False; + BOOL other_processes = True; + + read_only = ronly; + + DEBUG(5,("smb_shm_open : using shmem file %s to be of size %d\n",file_name,size)); + + smb_shm_fd = open(file_name, read_only?O_RDONLY:(O_RDWR|O_CREAT), + SHM_FILE_MODE); + + if ( smb_shm_fd < 0 ) + { + DEBUG(0,("ERROR smb_shm_open : open failed with code %s\n",strerror(errno))); + return NULL; + } + + if (!smb_shm_global_lock()) + { + DEBUG(0,("ERROR smb_shm_open : can't do smb_shm_global_lock\n")); + return NULL; + } + + if( (filesize = lseek(smb_shm_fd, 0, SEEK_END)) < 0) + { + DEBUG(0,("ERROR smb_shm_open : lseek failed with code %s\n",strerror(errno))); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + /* return the file offset to 0 to save on later seeks */ + lseek(smb_shm_fd,0,SEEK_SET); + + if (filesize == 0) + { + /* we just created a new one */ + created_new = True; + } + + /* to find out if some other process is already mapping the file, + we use a registration file containing the processids of the file mapping processes + */ + + /* construct processreg file name */ + strcpy(smb_shm_processreg_name, file_name); + strcat(smb_shm_processreg_name, ".processes"); + + if (!read_only && + !smb_shm_register_process(smb_shm_processreg_name, getpid(), &other_processes)) + { + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + if (!read_only && (created_new || !other_processes)) + { + /* we just created a new one, or are the first opener, lets set it size */ + if( ftruncate(smb_shm_fd, size) <0) + { + DEBUG(0,("ERROR smb_shm_open : ftruncate failed with code %s\n",strerror(errno))); + smb_shm_unregister_process(smb_shm_processreg_name, getpid()); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + /* paranoia */ + lseek(smb_shm_fd,0,SEEK_SET); + + filesize = size; + } + + if (size != filesize ) + { + /* the existing file has a different size and we are not the first opener. + Since another process is still using it, we will use the file size */ + DEBUG(0,("WARNING smb_shm_open : filesize (%d) != expected size (%d), using filesize\n",filesize,size)); + size = filesize; + } + + smb_shm_header_p = (struct SmbShmHeader *)mmap(NULL, size, + read_only?PROT_READ: + (PROT_READ | PROT_WRITE), + MAP_FILE | MAP_SHARED, + smb_shm_fd, 0); + /* WARNING, smb_shm_header_p can be different for different processes mapping the same file ! */ + if (smb_shm_header_p == (struct SmbShmHeader *)(-1)) + { + DEBUG(0,("ERROR smb_shm_open : mmap failed with code %s\n",strerror(errno))); + smb_shm_unregister_process(smb_shm_processreg_name, getpid()); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + + if (!read_only && (created_new || !other_processes)) + { + smb_shm_initialize(size); + /* Create the hash buckets for the share file entries. */ + smb_shm_create_hash_table( lp_shmem_hash_size() ); + } + else if (!smb_shm_validate_header(size) ) + { + /* existing file is corrupt, samba admin should remove it by hand */ + DEBUG(0,("ERROR smb_shm_open : corrupt shared mem file, remove it manually\n")); + munmap((caddr_t)smb_shm_header_p, size); + smb_shm_unregister_process(smb_shm_processreg_name, getpid()); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + smb_shm_global_unlock(); + return &shmops; +} + + #else /* FAST_SHARE_MODES */ int shmem_dummy_procedure(void) {return 0;} |