1*4882a593Smuzhiyun.. include:: ../disclaimer-ita.rst 2*4882a593Smuzhiyun 3*4882a593Smuzhiyun:Original: :ref:`Documentation/process/magic-number.rst <magicnumbers>` 4*4882a593Smuzhiyun:Translator: Federico Vaga <federico.vaga@vaga.pv.it> 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun.. _it_magicnumbers: 7*4882a593Smuzhiyun 8*4882a593SmuzhiyunI numeri magici di Linux 9*4882a593Smuzhiyun======================== 10*4882a593Smuzhiyun 11*4882a593SmuzhiyunQuesto documento è un registro dei numeri magici in uso. Quando 12*4882a593Smuzhiyunaggiungete un numero magico ad una struttura, dovreste aggiungerlo anche 13*4882a593Smuzhiyuna questo documento; la cosa migliore è che tutti i numeri magici usati 14*4882a593Smuzhiyundalle varie strutture siano unici. 15*4882a593Smuzhiyun 16*4882a593SmuzhiyunÈ **davvero** un'ottima idea proteggere le strutture dati del kernel con 17*4882a593Smuzhiyundei numeri magici. Questo vi permette in fase d'esecuzione di (a) verificare 18*4882a593Smuzhiyunse una struttura è stata malmenata, o (b) avete passato a una procedura la 19*4882a593Smuzhiyunstruttura errata. Quest'ultimo è molto utile - particolarmente quando si passa 20*4882a593Smuzhiyununa struttura dati tramite un puntatore void \*. Il codice tty, per esempio, 21*4882a593Smuzhiyuneffettua questa operazione con regolarità passando avanti e indietro le 22*4882a593Smuzhiyunstrutture specifiche per driver e discipline. 23*4882a593Smuzhiyun 24*4882a593SmuzhiyunPer utilizzare un numero magico, dovete dichiararlo all'inizio della struttura 25*4882a593Smuzhiyundati, come di seguito:: 26*4882a593Smuzhiyun 27*4882a593Smuzhiyun struct tty_ldisc { 28*4882a593Smuzhiyun int magic; 29*4882a593Smuzhiyun ... 30*4882a593Smuzhiyun }; 31*4882a593Smuzhiyun 32*4882a593SmuzhiyunPer favore, seguite questa direttiva quando aggiungerete migliorie al kernel! 33*4882a593SmuzhiyunMi ha risparmiato un numero illimitato di ore di debug, specialmente nei casi 34*4882a593Smuzhiyunpiù ostici dove si è andati oltre la dimensione di un vettore e la struttura 35*4882a593Smuzhiyundati che lo seguiva in memoria è stata sovrascritta. Seguendo questa 36*4882a593Smuzhiyundirettiva, questi casi vengono identificati velocemente e in sicurezza. 37*4882a593Smuzhiyun 38*4882a593SmuzhiyunRegistro dei cambiamenti:: 39*4882a593Smuzhiyun 40*4882a593Smuzhiyun Theodore Ts'o 41*4882a593Smuzhiyun 31 Mar 94 42*4882a593Smuzhiyun 43*4882a593Smuzhiyun La tabella magica è aggiornata a Linux 2.1.55. 44*4882a593Smuzhiyun 45*4882a593Smuzhiyun Michael Chastain 46*4882a593Smuzhiyun <mailto:mec@shout.net> 47*4882a593Smuzhiyun 22 Sep 1997 48*4882a593Smuzhiyun 49*4882a593Smuzhiyun Ora dovrebbe essere aggiornata a Linux 2.1.112. Dato che 50*4882a593Smuzhiyun siamo in un momento di congelamento delle funzionalità 51*4882a593Smuzhiyun (*feature freeze*) è improbabile che qualcosa cambi prima 52*4882a593Smuzhiyun della versione 2.2.x. Le righe sono ordinate secondo il 53*4882a593Smuzhiyun campo numero. 54*4882a593Smuzhiyun 55*4882a593Smuzhiyun Krzysztof G. Baranowski 56*4882a593Smuzhiyun <mailto: kgb@knm.org.pl> 57*4882a593Smuzhiyun 29 Jul 1998 58*4882a593Smuzhiyun 59*4882a593Smuzhiyun Aggiornamento della tabella a Linux 2.5.45. Giusti nel congelamento 60*4882a593Smuzhiyun delle funzionalità ma è comunque possibile che qualche nuovo 61*4882a593Smuzhiyun numero magico s'intrufoli prima del kernel 2.6.x. 62*4882a593Smuzhiyun 63*4882a593Smuzhiyun Petr Baudis 64*4882a593Smuzhiyun <pasky@ucw.cz> 65*4882a593Smuzhiyun 03 Nov 2002 66*4882a593Smuzhiyun 67*4882a593Smuzhiyun Aggiornamento della tabella magica a Linux 2.5.74. 68*4882a593Smuzhiyun 69*4882a593Smuzhiyun Fabian Frederick 70*4882a593Smuzhiyun <ffrederick@users.sourceforge.net> 71*4882a593Smuzhiyun 09 Jul 2003 72*4882a593Smuzhiyun 73*4882a593Smuzhiyun 74*4882a593Smuzhiyun===================== ================ ======================== ========================================== 75*4882a593SmuzhiyunNome magico Numero Struttura File 76*4882a593Smuzhiyun===================== ================ ======================== ========================================== 77*4882a593SmuzhiyunPG_MAGIC 'P' pg_{read,write}_hdr ``include/linux/pg.h`` 78*4882a593SmuzhiyunCMAGIC 0x0111 user ``include/linux/a.out.h`` 79*4882a593SmuzhiyunMKISS_DRIVER_MAGIC 0x04bf mkiss_channel ``drivers/net/mkiss.h`` 80*4882a593SmuzhiyunHDLC_MAGIC 0x239e n_hdlc ``drivers/char/n_hdlc.c`` 81*4882a593SmuzhiyunAPM_BIOS_MAGIC 0x4101 apm_user ``arch/x86/kernel/apm_32.c`` 82*4882a593SmuzhiyunCYCLADES_MAGIC 0x4359 cyclades_port ``include/linux/cyclades.h`` 83*4882a593SmuzhiyunDB_MAGIC 0x4442 fc_info ``drivers/net/iph5526_novram.c`` 84*4882a593SmuzhiyunDL_MAGIC 0x444d fc_info ``drivers/net/iph5526_novram.c`` 85*4882a593SmuzhiyunFASYNC_MAGIC 0x4601 fasync_struct ``include/linux/fs.h`` 86*4882a593SmuzhiyunFF_MAGIC 0x4646 fc_info ``drivers/net/iph5526_novram.c`` 87*4882a593SmuzhiyunISICOM_MAGIC 0x4d54 isi_port ``include/linux/isicom.h`` 88*4882a593SmuzhiyunPTY_MAGIC 0x5001 ``drivers/char/pty.c`` 89*4882a593SmuzhiyunPPP_MAGIC 0x5002 ppp ``include/linux/if_pppvar.h`` 90*4882a593SmuzhiyunSSTATE_MAGIC 0x5302 serial_state ``include/linux/serial.h`` 91*4882a593SmuzhiyunSLIP_MAGIC 0x5302 slip ``drivers/net/slip.h`` 92*4882a593SmuzhiyunSTRIP_MAGIC 0x5303 strip ``drivers/net/strip.c`` 93*4882a593SmuzhiyunX25_ASY_MAGIC 0x5303 x25_asy ``drivers/net/x25_asy.h`` 94*4882a593SmuzhiyunSIXPACK_MAGIC 0x5304 sixpack ``drivers/net/hamradio/6pack.h`` 95*4882a593SmuzhiyunAX25_MAGIC 0x5316 ax_disp ``drivers/net/mkiss.h`` 96*4882a593SmuzhiyunTTY_MAGIC 0x5401 tty_struct ``include/linux/tty.h`` 97*4882a593SmuzhiyunMGSL_MAGIC 0x5401 mgsl_info ``drivers/char/synclink.c`` 98*4882a593SmuzhiyunTTY_DRIVER_MAGIC 0x5402 tty_driver ``include/linux/tty_driver.h`` 99*4882a593SmuzhiyunMGSLPC_MAGIC 0x5402 mgslpc_info ``drivers/char/pcmcia/synclink_cs.c`` 100*4882a593SmuzhiyunTTY_LDISC_MAGIC 0x5403 tty_ldisc ``include/linux/tty_ldisc.h`` 101*4882a593SmuzhiyunUSB_SERIAL_MAGIC 0x6702 usb_serial ``drivers/usb/serial/usb-serial.h`` 102*4882a593SmuzhiyunFULL_DUPLEX_MAGIC 0x6969 ``drivers/net/ethernet/dec/tulip/de2104x.c`` 103*4882a593SmuzhiyunUSB_BLUETOOTH_MAGIC 0x6d02 usb_bluetooth ``drivers/usb/class/bluetty.c`` 104*4882a593SmuzhiyunRFCOMM_TTY_MAGIC 0x6d02 ``net/bluetooth/rfcomm/tty.c`` 105*4882a593SmuzhiyunUSB_SERIAL_PORT_MAGIC 0x7301 usb_serial_port ``drivers/usb/serial/usb-serial.h`` 106*4882a593SmuzhiyunCG_MAGIC 0x00090255 ufs_cylinder_group ``include/linux/ufs_fs.h`` 107*4882a593SmuzhiyunRPORT_MAGIC 0x00525001 r_port ``drivers/char/rocket_int.h`` 108*4882a593SmuzhiyunLSEMAGIC 0x05091998 lse ``drivers/fc4/fc.c`` 109*4882a593SmuzhiyunGDTIOCTL_MAGIC 0x06030f07 gdth_iowr_str ``drivers/scsi/gdth_ioctl.h`` 110*4882a593SmuzhiyunRIEBL_MAGIC 0x09051990 ``drivers/net/atarilance.c`` 111*4882a593SmuzhiyunNBD_REQUEST_MAGIC 0x12560953 nbd_request ``include/linux/nbd.h`` 112*4882a593SmuzhiyunRED_MAGIC2 0x170fc2a5 (any) ``mm/slab.c`` 113*4882a593SmuzhiyunBAYCOM_MAGIC 0x19730510 baycom_state ``drivers/net/baycom_epp.c`` 114*4882a593SmuzhiyunISDN_X25IFACE_MAGIC 0x1e75a2b9 isdn_x25iface_proto_data ``drivers/isdn/isdn_x25iface.h`` 115*4882a593SmuzhiyunECP_MAGIC 0x21504345 cdkecpsig ``include/linux/cdk.h`` 116*4882a593SmuzhiyunLSOMAGIC 0x27091997 lso ``drivers/fc4/fc.c`` 117*4882a593SmuzhiyunLSMAGIC 0x2a3b4d2a ls ``drivers/fc4/fc.c`` 118*4882a593SmuzhiyunWANPIPE_MAGIC 0x414C4453 sdla_{dump,exec} ``include/linux/wanpipe.h`` 119*4882a593SmuzhiyunCS_CARD_MAGIC 0x43525553 cs_card ``sound/oss/cs46xx.c`` 120*4882a593SmuzhiyunLABELCL_MAGIC 0x4857434c labelcl_info_s ``include/asm/ia64/sn/labelcl.h`` 121*4882a593SmuzhiyunISDN_ASYNC_MAGIC 0x49344C01 modem_info ``include/linux/isdn.h`` 122*4882a593SmuzhiyunCTC_ASYNC_MAGIC 0x49344C01 ctc_tty_info ``drivers/s390/net/ctctty.c`` 123*4882a593SmuzhiyunISDN_NET_MAGIC 0x49344C02 isdn_net_local_s ``drivers/isdn/i4l/isdn_net_lib.h`` 124*4882a593SmuzhiyunSAVEKMSG_MAGIC2 0x4B4D5347 savekmsg ``arch/*/amiga/config.c`` 125*4882a593SmuzhiyunCS_STATE_MAGIC 0x4c4f4749 cs_state ``sound/oss/cs46xx.c`` 126*4882a593SmuzhiyunSLAB_C_MAGIC 0x4f17a36d kmem_cache ``mm/slab.c`` 127*4882a593SmuzhiyunCOW_MAGIC 0x4f4f4f4d cow_header_v1 ``arch/um/drivers/ubd_user.c`` 128*4882a593SmuzhiyunI810_CARD_MAGIC 0x5072696E i810_card ``sound/oss/i810_audio.c`` 129*4882a593SmuzhiyunTRIDENT_CARD_MAGIC 0x5072696E trident_card ``sound/oss/trident.c`` 130*4882a593SmuzhiyunROUTER_MAGIC 0x524d4157 wan_device [in ``wanrouter.h`` pre 3.9] 131*4882a593SmuzhiyunSAVEKMSG_MAGIC1 0x53415645 savekmsg ``arch/*/amiga/config.c`` 132*4882a593SmuzhiyunGDA_MAGIC 0x58464552 gda ``arch/mips/include/asm/sn/gda.h`` 133*4882a593SmuzhiyunRED_MAGIC1 0x5a2cf071 (any) ``mm/slab.c`` 134*4882a593SmuzhiyunEEPROM_MAGIC_VALUE 0x5ab478d2 lanai_dev ``drivers/atm/lanai.c`` 135*4882a593SmuzhiyunHDLCDRV_MAGIC 0x5ac6e778 hdlcdrv_state ``include/linux/hdlcdrv.h`` 136*4882a593SmuzhiyunPCXX_MAGIC 0x5c6df104 channel ``drivers/char/pcxx.h`` 137*4882a593SmuzhiyunKV_MAGIC 0x5f4b565f kernel_vars_s ``arch/mips/include/asm/sn/klkernvars.h`` 138*4882a593SmuzhiyunI810_STATE_MAGIC 0x63657373 i810_state ``sound/oss/i810_audio.c`` 139*4882a593SmuzhiyunTRIDENT_STATE_MAGIC 0x63657373 trient_state ``sound/oss/trident.c`` 140*4882a593SmuzhiyunM3_CARD_MAGIC 0x646e6f50 m3_card ``sound/oss/maestro3.c`` 141*4882a593SmuzhiyunFW_HEADER_MAGIC 0x65726F66 fw_header ``drivers/atm/fore200e.h`` 142*4882a593SmuzhiyunSLOT_MAGIC 0x67267321 slot ``drivers/hotplug/cpqphp.h`` 143*4882a593SmuzhiyunSLOT_MAGIC 0x67267322 slot ``drivers/hotplug/acpiphp.h`` 144*4882a593SmuzhiyunLO_MAGIC 0x68797548 nbd_device ``include/linux/nbd.h`` 145*4882a593SmuzhiyunOPROFILE_MAGIC 0x6f70726f super_block ``drivers/oprofile/oprofilefs.h`` 146*4882a593SmuzhiyunM3_STATE_MAGIC 0x734d724d m3_state ``sound/oss/maestro3.c`` 147*4882a593SmuzhiyunVMALLOC_MAGIC 0x87654320 snd_alloc_track ``sound/core/memory.c`` 148*4882a593SmuzhiyunKMALLOC_MAGIC 0x87654321 snd_alloc_track ``sound/core/memory.c`` 149*4882a593SmuzhiyunPWC_MAGIC 0x89DC10AB pwc_device ``drivers/usb/media/pwc.h`` 150*4882a593SmuzhiyunNBD_REPLY_MAGIC 0x96744668 nbd_reply ``include/linux/nbd.h`` 151*4882a593SmuzhiyunENI155_MAGIC 0xa54b872d midway_eprom ``drivers/atm/eni.h`` 152*4882a593SmuzhiyunCODA_MAGIC 0xC0DAC0DA coda_file_info ``fs/coda/coda_fs_i.h`` 153*4882a593SmuzhiyunDPMEM_MAGIC 0xc0ffee11 gdt_pci_sram ``drivers/scsi/gdth.h`` 154*4882a593SmuzhiyunYAM_MAGIC 0xF10A7654 yam_port ``drivers/net/hamradio/yam.c`` 155*4882a593SmuzhiyunCCB_MAGIC 0xf2691ad2 ccb ``drivers/scsi/ncr53c8xx.c`` 156*4882a593SmuzhiyunQUEUE_MAGIC_FREE 0xf7e1c9a3 queue_entry ``drivers/scsi/arm/queue.c`` 157*4882a593SmuzhiyunQUEUE_MAGIC_USED 0xf7e1cc33 queue_entry ``drivers/scsi/arm/queue.c`` 158*4882a593SmuzhiyunHTB_CMAGIC 0xFEFAFEF1 htb_class ``net/sched/sch_htb.c`` 159*4882a593SmuzhiyunNMI_MAGIC 0x48414d4d455201 nmi_s ``arch/mips/include/asm/sn/nmi.h`` 160*4882a593Smuzhiyun===================== ================ ======================== ========================================== 161*4882a593Smuzhiyun 162*4882a593SmuzhiyunDa notare che ci sono anche dei numeri magici specifici per driver nel 163*4882a593Smuzhiyun*sound memory management*. Consultate ``include/sound/sndmagic.h`` per una 164*4882a593Smuzhiyunlista completa. Molti driver audio OSS hanno i loro numeri magici costruiti a 165*4882a593Smuzhiyunpartire dall'identificativo PCI della scheda audio - nemmeno questi sono 166*4882a593Smuzhiyunelencati in questo file. 167*4882a593Smuzhiyun 168*4882a593SmuzhiyunIl file-system HFS è un altro grande utilizzatore di numeri magici - potete 169*4882a593Smuzhiyuntrovarli qui ``fs/hfs/hfs.h``. 170