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Commit 9a11e153 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
Browse files

Documentation/magic-number.txt: convert it to ReST markup 



- add a title for the document;
- convert the table;
- use quote block for the changelog;
- use monotonic fonts for file names;
- adjust whitespaces and blank lines;
- add it to the user's book.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 8887adde

Documentation/magic-number.txt

+111 −105
Original line number Diff line number Diff line 
Linux magic numbers

===================



This file is a registry of magic numbers which are in use.  When you

add a magic number to a structure, you should also add it to this

file, since it is best if the magic numbers used by various structures

are unique.



It is a *very* good idea to protect kernel data structures with magic

It is a **very** good idea to protect kernel data structures with magic

numbers.  This allows you to check at run time whether (a) a structure

has been clobbered, or (b) you've passed the wrong structure to a

routine.  This last is especially useful --- particularly when you are
@@ -12,7 +15,7 @@ for example, does this frequently to pass driver-specific and line 
discipline-specific structures back and forth.



The way to use magic numbers is to declare then at the beginning of

the structure, like so:

the structure, like so::



	struct tty_ldisc {

		int	magic;
@@ -25,6 +28,8 @@ especially in the screwy cases where an array has been overrun and 
structures following the array have been overwritten.  Using this

discipline, these cases get detected quickly and safely.



Changelog::



					Theodore Ts'o

					31 Mar 94
@@ -58,101 +63,102 @@ Updated the magic table to Linux 2.5.74. 
					09 Jul 2003





===================== ================ ======================== ==========================================

Magic Name            Number           Structure                File

===========================================================================

PG_MAGIC              'P'         pg_{read,write}_hdr include/linux/pg.h

CMAGIC                0x0111      user              include/linux/a.out.h

MKISS_DRIVER_MAGIC    0x04bf      mkiss_channel     drivers/net/mkiss.h

HDLC_MAGIC            0x239e      n_hdlc            drivers/char/n_hdlc.c

APM_BIOS_MAGIC        0x4101      apm_user          arch/x86/kernel/apm_32.c

CYCLADES_MAGIC        0x4359      cyclades_port     include/linux/cyclades.h

DB_MAGIC              0x4442      fc_info           drivers/net/iph5526_novram.c

DL_MAGIC              0x444d      fc_info           drivers/net/iph5526_novram.c

FASYNC_MAGIC          0x4601      fasync_struct     include/linux/fs.h

FF_MAGIC              0x4646      fc_info           drivers/net/iph5526_novram.c

ISICOM_MAGIC          0x4d54      isi_port          include/linux/isicom.h

PTY_MAGIC             0x5001                        drivers/char/pty.c

PPP_MAGIC             0x5002      ppp               include/linux/if_pppvar.h

SERIAL_MAGIC          0x5301      async_struct      include/linux/serial.h

SSTATE_MAGIC          0x5302      serial_state      include/linux/serial.h

SLIP_MAGIC            0x5302      slip              drivers/net/slip.h

STRIP_MAGIC           0x5303      strip             drivers/net/strip.c

X25_ASY_MAGIC         0x5303      x25_asy           drivers/net/x25_asy.h

SIXPACK_MAGIC         0x5304      sixpack           drivers/net/hamradio/6pack.h

AX25_MAGIC            0x5316      ax_disp           drivers/net/mkiss.h

TTY_MAGIC             0x5401      tty_struct        include/linux/tty.h

MGSL_MAGIC            0x5401      mgsl_info         drivers/char/synclink.c

TTY_DRIVER_MAGIC      0x5402      tty_driver        include/linux/tty_driver.h

MGSLPC_MAGIC          0x5402      mgslpc_info       drivers/char/pcmcia/synclink_cs.c

TTY_LDISC_MAGIC       0x5403      tty_ldisc         include/linux/tty_ldisc.h

USB_SERIAL_MAGIC      0x6702      usb_serial        drivers/usb/serial/usb-serial.h

FULL_DUPLEX_MAGIC     0x6969                        drivers/net/ethernet/dec/tulip/de2104x.c

USB_BLUETOOTH_MAGIC   0x6d02      usb_bluetooth     drivers/usb/class/bluetty.c

RFCOMM_TTY_MAGIC      0x6d02                        net/bluetooth/rfcomm/tty.c

USB_SERIAL_PORT_MAGIC 0x7301      usb_serial_port   drivers/usb/serial/usb-serial.h

CG_MAGIC              0x00090255  ufs_cylinder_group include/linux/ufs_fs.h

RPORT_MAGIC           0x00525001  r_port            drivers/char/rocket_int.h

LSEMAGIC              0x05091998  lse               drivers/fc4/fc.c

GDTIOCTL_MAGIC        0x06030f07  gdth_iowr_str     drivers/scsi/gdth_ioctl.h

RIEBL_MAGIC           0x09051990                    drivers/net/atarilance.c

NBD_REQUEST_MAGIC     0x12560953  nbd_request       include/linux/nbd.h

RED_MAGIC2            0x170fc2a5  (any)             mm/slab.c

BAYCOM_MAGIC          0x19730510  baycom_state      drivers/net/baycom_epp.c

ISDN_X25IFACE_MAGIC   0x1e75a2b9  isdn_x25iface_proto_data

                                                    drivers/isdn/isdn_x25iface.h

ECP_MAGIC             0x21504345  cdkecpsig         include/linux/cdk.h

LSOMAGIC              0x27091997  lso               drivers/fc4/fc.c

LSMAGIC               0x2a3b4d2a  ls                drivers/fc4/fc.c

WANPIPE_MAGIC         0x414C4453  sdla_{dump,exec}  include/linux/wanpipe.h

CS_CARD_MAGIC         0x43525553  cs_card           sound/oss/cs46xx.c

LABELCL_MAGIC         0x4857434c  labelcl_info_s    include/asm/ia64/sn/labelcl.h

ISDN_ASYNC_MAGIC      0x49344C01  modem_info        include/linux/isdn.h

CTC_ASYNC_MAGIC       0x49344C01  ctc_tty_info      drivers/s390/net/ctctty.c

ISDN_NET_MAGIC        0x49344C02  isdn_net_local_s  drivers/isdn/i4l/isdn_net_lib.h

SAVEKMSG_MAGIC2       0x4B4D5347  savekmsg          arch/*/amiga/config.c

CS_STATE_MAGIC        0x4c4f4749  cs_state          sound/oss/cs46xx.c

SLAB_C_MAGIC          0x4f17a36d  kmem_cache        mm/slab.c

COW_MAGIC             0x4f4f4f4d  cow_header_v1     arch/um/drivers/ubd_user.c

I810_CARD_MAGIC       0x5072696E  i810_card         sound/oss/i810_audio.c

TRIDENT_CARD_MAGIC    0x5072696E  trident_card      sound/oss/trident.c

ROUTER_MAGIC          0x524d4157  wan_device        [in wanrouter.h pre 3.9]

SAVEKMSG_MAGIC1       0x53415645  savekmsg          arch/*/amiga/config.c

GDA_MAGIC             0x58464552  gda               arch/mips/include/asm/sn/gda.h

RED_MAGIC1            0x5a2cf071  (any)             mm/slab.c

EEPROM_MAGIC_VALUE    0x5ab478d2  lanai_dev         drivers/atm/lanai.c

HDLCDRV_MAGIC         0x5ac6e778  hdlcdrv_state     include/linux/hdlcdrv.h

PCXX_MAGIC            0x5c6df104  channel           drivers/char/pcxx.h

KV_MAGIC              0x5f4b565f  kernel_vars_s     arch/mips/include/asm/sn/klkernvars.h

I810_STATE_MAGIC      0x63657373  i810_state        sound/oss/i810_audio.c

TRIDENT_STATE_MAGIC   0x63657373  trient_state      sound/oss/trident.c

M3_CARD_MAGIC         0x646e6f50  m3_card           sound/oss/maestro3.c

FW_HEADER_MAGIC       0x65726F66  fw_header         drivers/atm/fore200e.h

SLOT_MAGIC            0x67267321  slot              drivers/hotplug/cpqphp.h

SLOT_MAGIC            0x67267322  slot              drivers/hotplug/acpiphp.h

LO_MAGIC              0x68797548  nbd_device        include/linux/nbd.h

OPROFILE_MAGIC        0x6f70726f  super_block       drivers/oprofile/oprofilefs.h

M3_STATE_MAGIC        0x734d724d  m3_state          sound/oss/maestro3.c

VMALLOC_MAGIC         0x87654320  snd_alloc_track   sound/core/memory.c

KMALLOC_MAGIC         0x87654321  snd_alloc_track   sound/core/memory.c

PWC_MAGIC             0x89DC10AB  pwc_device        drivers/usb/media/pwc.h

NBD_REPLY_MAGIC       0x96744668  nbd_reply         include/linux/nbd.h

ENI155_MAGIC          0xa54b872d  midway_eprom	    drivers/atm/eni.h

CODA_MAGIC            0xC0DAC0DA  coda_file_info    fs/coda/coda_fs_i.h

DPMEM_MAGIC           0xc0ffee11  gdt_pci_sram      drivers/scsi/gdth.h

YAM_MAGIC             0xF10A7654  yam_port          drivers/net/hamradio/yam.c

CCB_MAGIC             0xf2691ad2  ccb               drivers/scsi/ncr53c8xx.c

QUEUE_MAGIC_FREE      0xf7e1c9a3  queue_entry       drivers/scsi/arm/queue.c

QUEUE_MAGIC_USED      0xf7e1cc33  queue_entry       drivers/scsi/arm/queue.c

HTB_CMAGIC            0xFEFAFEF1  htb_class         net/sched/sch_htb.c

NMI_MAGIC             0x48414d4d455201 nmi_s        arch/mips/include/asm/sn/nmi.h

===================== ================ ======================== ==========================================

PG_MAGIC              'P'              pg_{read,write}_hdr      ``include/linux/pg.h``

CMAGIC                0x0111           user                     ``include/linux/a.out.h``

MKISS_DRIVER_MAGIC    0x04bf           mkiss_channel            ``drivers/net/mkiss.h``

HDLC_MAGIC            0x239e           n_hdlc                   ``drivers/char/n_hdlc.c``

APM_BIOS_MAGIC        0x4101           apm_user                 ``arch/x86/kernel/apm_32.c``

CYCLADES_MAGIC        0x4359           cyclades_port            ``include/linux/cyclades.h``

DB_MAGIC              0x4442           fc_info                  ``drivers/net/iph5526_novram.c``

DL_MAGIC              0x444d           fc_info                  ``drivers/net/iph5526_novram.c``

FASYNC_MAGIC          0x4601           fasync_struct            ``include/linux/fs.h``

FF_MAGIC              0x4646           fc_info                  ``drivers/net/iph5526_novram.c``

ISICOM_MAGIC          0x4d54           isi_port                 ``include/linux/isicom.h``

PTY_MAGIC             0x5001                                    ``drivers/char/pty.c``

PPP_MAGIC             0x5002           ppp                      ``include/linux/if_pppvar.h``

SERIAL_MAGIC          0x5301           async_struct             ``include/linux/serial.h``

SSTATE_MAGIC          0x5302           serial_state             ``include/linux/serial.h``

SLIP_MAGIC            0x5302           slip                     ``drivers/net/slip.h``

STRIP_MAGIC           0x5303           strip                    ``drivers/net/strip.c``

X25_ASY_MAGIC         0x5303           x25_asy                  ``drivers/net/x25_asy.h``

SIXPACK_MAGIC         0x5304           sixpack                  ``drivers/net/hamradio/6pack.h``

AX25_MAGIC            0x5316           ax_disp                  ``drivers/net/mkiss.h``

TTY_MAGIC             0x5401           tty_struct               ``include/linux/tty.h``

MGSL_MAGIC            0x5401           mgsl_info                ``drivers/char/synclink.c``

TTY_DRIVER_MAGIC      0x5402           tty_driver               ``include/linux/tty_driver.h``

MGSLPC_MAGIC          0x5402           mgslpc_info              ``drivers/char/pcmcia/synclink_cs.c``

TTY_LDISC_MAGIC       0x5403           tty_ldisc                ``include/linux/tty_ldisc.h``

USB_SERIAL_MAGIC      0x6702           usb_serial               ``drivers/usb/serial/usb-serial.h``

FULL_DUPLEX_MAGIC     0x6969                                    ``drivers/net/ethernet/dec/tulip/de2104x.c``

USB_BLUETOOTH_MAGIC   0x6d02           usb_bluetooth            ``drivers/usb/class/bluetty.c``

RFCOMM_TTY_MAGIC      0x6d02                                    ``net/bluetooth/rfcomm/tty.c``

USB_SERIAL_PORT_MAGIC 0x7301           usb_serial_port          ``drivers/usb/serial/usb-serial.h``

CG_MAGIC              0x00090255       ufs_cylinder_group       ``include/linux/ufs_fs.h``

RPORT_MAGIC           0x00525001       r_port                   ``drivers/char/rocket_int.h``

LSEMAGIC              0x05091998       lse                      ``drivers/fc4/fc.c``

GDTIOCTL_MAGIC        0x06030f07       gdth_iowr_str            ``drivers/scsi/gdth_ioctl.h``

RIEBL_MAGIC           0x09051990                                ``drivers/net/atarilance.c``

NBD_REQUEST_MAGIC     0x12560953       nbd_request              ``include/linux/nbd.h``

RED_MAGIC2            0x170fc2a5       (any)                    ``mm/slab.c``

BAYCOM_MAGIC          0x19730510       baycom_state             ``drivers/net/baycom_epp.c``

ISDN_X25IFACE_MAGIC   0x1e75a2b9       isdn_x25iface_proto_data ``drivers/isdn/isdn_x25iface.h``

ECP_MAGIC             0x21504345       cdkecpsig                ``include/linux/cdk.h``

LSOMAGIC              0x27091997       lso                      ``drivers/fc4/fc.c``

LSMAGIC               0x2a3b4d2a       ls                       ``drivers/fc4/fc.c``

WANPIPE_MAGIC         0x414C4453       sdla_{dump,exec}         ``include/linux/wanpipe.h``

CS_CARD_MAGIC         0x43525553       cs_card                  ``sound/oss/cs46xx.c``

LABELCL_MAGIC         0x4857434c       labelcl_info_s           ``include/asm/ia64/sn/labelcl.h``

ISDN_ASYNC_MAGIC      0x49344C01       modem_info               ``include/linux/isdn.h``

CTC_ASYNC_MAGIC       0x49344C01       ctc_tty_info             ``drivers/s390/net/ctctty.c``

ISDN_NET_MAGIC        0x49344C02       isdn_net_local_s         ``drivers/isdn/i4l/isdn_net_lib.h``

SAVEKMSG_MAGIC2       0x4B4D5347       savekmsg                 ``arch/*/amiga/config.c``

CS_STATE_MAGIC        0x4c4f4749       cs_state                 ``sound/oss/cs46xx.c``

SLAB_C_MAGIC          0x4f17a36d       kmem_cache               ``mm/slab.c``

COW_MAGIC             0x4f4f4f4d       cow_header_v1            ``arch/um/drivers/ubd_user.c``

I810_CARD_MAGIC       0x5072696E       i810_card                ``sound/oss/i810_audio.c``

TRIDENT_CARD_MAGIC    0x5072696E       trident_card             ``sound/oss/trident.c``

ROUTER_MAGIC          0x524d4157       wan_device               [in ``wanrouter.h`` pre 3.9]

SAVEKMSG_MAGIC1       0x53415645       savekmsg                 ``arch/*/amiga/config.c``

GDA_MAGIC             0x58464552       gda                      ``arch/mips/include/asm/sn/gda.h``

RED_MAGIC1            0x5a2cf071       (any)                    ``mm/slab.c``

EEPROM_MAGIC_VALUE    0x5ab478d2       lanai_dev                ``drivers/atm/lanai.c``

HDLCDRV_MAGIC         0x5ac6e778       hdlcdrv_state            ``include/linux/hdlcdrv.h``

PCXX_MAGIC            0x5c6df104       channel                  ``drivers/char/pcxx.h``

KV_MAGIC              0x5f4b565f       kernel_vars_s            ``arch/mips/include/asm/sn/klkernvars.h``

I810_STATE_MAGIC      0x63657373       i810_state               ``sound/oss/i810_audio.c``

TRIDENT_STATE_MAGIC   0x63657373       trient_state             ``sound/oss/trident.c``

M3_CARD_MAGIC         0x646e6f50       m3_card                  ``sound/oss/maestro3.c``

FW_HEADER_MAGIC       0x65726F66       fw_header                ``drivers/atm/fore200e.h``

SLOT_MAGIC            0x67267321       slot                     ``drivers/hotplug/cpqphp.h``

SLOT_MAGIC            0x67267322       slot                     ``drivers/hotplug/acpiphp.h``

LO_MAGIC              0x68797548       nbd_device               ``include/linux/nbd.h``

OPROFILE_MAGIC        0x6f70726f       super_block              ``drivers/oprofile/oprofilefs.h``

M3_STATE_MAGIC        0x734d724d       m3_state                 ``sound/oss/maestro3.c``

VMALLOC_MAGIC         0x87654320       snd_alloc_track          ``sound/core/memory.c``

KMALLOC_MAGIC         0x87654321       snd_alloc_track          ``sound/core/memory.c``

PWC_MAGIC             0x89DC10AB       pwc_device               ``drivers/usb/media/pwc.h``

NBD_REPLY_MAGIC       0x96744668       nbd_reply                ``include/linux/nbd.h``

ENI155_MAGIC          0xa54b872d       midway_eprom	        ``drivers/atm/eni.h``

CODA_MAGIC            0xC0DAC0DA       coda_file_info           ``fs/coda/coda_fs_i.h``

DPMEM_MAGIC           0xc0ffee11       gdt_pci_sram             ``drivers/scsi/gdth.h``

YAM_MAGIC             0xF10A7654       yam_port                 ``drivers/net/hamradio/yam.c``

CCB_MAGIC             0xf2691ad2       ccb                      ``drivers/scsi/ncr53c8xx.c``

QUEUE_MAGIC_FREE      0xf7e1c9a3       queue_entry              ``drivers/scsi/arm/queue.c``

QUEUE_MAGIC_USED      0xf7e1cc33       queue_entry              ``drivers/scsi/arm/queue.c``

HTB_CMAGIC            0xFEFAFEF1       htb_class                ``net/sched/sch_htb.c``

NMI_MAGIC             0x48414d4d455201 nmi_s                    ``arch/mips/include/asm/sn/nmi.h``

===================== ================ ======================== ==========================================



Note that there are also defined special per-driver magic numbers in sound

memory management. See include/sound/sndmagic.h for complete list of them. Many

memory management. See ``include/sound/sndmagic.h`` for complete list of them. Many

OSS sound drivers have their magic numbers constructed from the soundcard PCI

ID - these are not listed here as well.



IrDA subsystem also uses large number of own magic numbers, see

include/net/irda/irda.h for a complete list of them.

``include/net/irda/irda.h`` for a complete list of them.



HFS is another larger user of magic numbers - you can find them in

fs/hfs/hfs.h.
 
``fs/hfs/hfs.h``.