diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/magic-number.txt |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'Documentation/magic-number.txt')
-rw-r--r-- | Documentation/magic-number.txt | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/Documentation/magic-number.txt b/Documentation/magic-number.txt new file mode 100644 index 000000000000..bd8eefa17587 --- /dev/null +++ b/Documentation/magic-number.txt | |||
@@ -0,0 +1,174 @@ | |||
1 | This file is a registry of magic numbers which are in use. When you | ||
2 | add a magic number to a structure, you should also add it to this | ||
3 | file, since it is best if the magic numbers used by various structures | ||
4 | are unique. | ||
5 | |||
6 | It is a *very* good idea to protect kernel data structures with magic | ||
7 | numbers. This allows you to check at run time whether (a) a structure | ||
8 | has been clobbered, or (b) you've passed the wrong structure to a | ||
9 | routine. This last is especially useful --- particularly when you are | ||
10 | passing pointers to structures via a void * pointer. The tty code, | ||
11 | for example, does this frequently to pass driver-specific and line | ||
12 | discipline-specific structures back and forth. | ||
13 | |||
14 | The way to use magic numbers is to declare then at the beginning of | ||
15 | the structure, like so: | ||
16 | |||
17 | struct tty_ldisc { | ||
18 | int magic; | ||
19 | ... | ||
20 | }; | ||
21 | |||
22 | Please follow this discipline when you are adding future enhancements | ||
23 | to the kernel! It has saved me countless hours of debugging, | ||
24 | especially in the screwy cases where an array has been overrun and | ||
25 | structures following the array have been overwritten. Using this | ||
26 | discipline, these cases get detected quickly and safely. | ||
27 | |||
28 | Theodore Ts'o | ||
29 | 31 Mar 94 | ||
30 | |||
31 | The magic table is current to Linux 2.1.55. | ||
32 | |||
33 | Michael Chastain | ||
34 | <mailto:mec@shout.net> | ||
35 | 22 Sep 1997 | ||
36 | |||
37 | Now it should be up to date with Linux 2.1.112. Because | ||
38 | we are in feature freeze time it is very unlikely that | ||
39 | something will change before 2.2.x. The entries are | ||
40 | sorted by number field. | ||
41 | |||
42 | Krzysztof G. Baranowski | ||
43 | <mailto: kgb@knm.org.pl> | ||
44 | 29 Jul 1998 | ||
45 | |||
46 | Updated the magic table to Linux 2.5.45. Right over the feature freeze, | ||
47 | but it is possible that some new magic numbers will sneak into the | ||
48 | kernel before 2.6.x yet. | ||
49 | |||
50 | Petr Baudis | ||
51 | <pasky@ucw.cz> | ||
52 | 03 Nov 2002 | ||
53 | |||
54 | Updated the magic table to Linux 2.5.74. | ||
55 | |||
56 | Fabian Frederick | ||
57 | <ffrederick@users.sourceforge.net> | ||
58 | 09 Jul 2003 | ||
59 | |||
60 | |||
61 | Magic Name Number Structure File | ||
62 | =========================================================================== | ||
63 | PG_MAGIC 'P' pg_{read,write}_hdr include/linux/pg.h | ||
64 | CMAGIC 0x0111 user include/linux/a.out.h | ||
65 | MKISS_DRIVER_MAGIC 0x04bf mkiss_channel drivers/net/mkiss.h | ||
66 | RISCOM8_MAGIC 0x0907 riscom_port drivers/char/riscom8.h | ||
67 | SPECIALIX_MAGIC 0x0907 specialix_port drivers/char/specialix_io8.h | ||
68 | AURORA_MAGIC 0x0A18 Aurora_port drivers/sbus/char/aurora.h | ||
69 | HDLC_MAGIC 0x239e n_hdlc drivers/char/n_hdlc.c | ||
70 | APM_BIOS_MAGIC 0x4101 apm_user arch/i386/kernel/apm.c | ||
71 | CYCLADES_MAGIC 0x4359 cyclades_port include/linux/cyclades.h | ||
72 | DB_MAGIC 0x4442 fc_info drivers/net/iph5526_novram.c | ||
73 | DL_MAGIC 0x444d fc_info drivers/net/iph5526_novram.c | ||
74 | FASYNC_MAGIC 0x4601 fasync_struct include/linux/fs.h | ||
75 | FF_MAGIC 0x4646 fc_info drivers/net/iph5526_novram.c | ||
76 | ISICOM_MAGIC 0x4d54 isi_port include/linux/isicom.h | ||
77 | PTY_MAGIC 0x5001 drivers/char/pty.c | ||
78 | PPP_MAGIC 0x5002 ppp include/linux/if_pppvar.h | ||
79 | SERIAL_MAGIC 0x5301 async_struct include/linux/serial.h | ||
80 | SSTATE_MAGIC 0x5302 serial_state include/linux/serial.h | ||
81 | SLIP_MAGIC 0x5302 slip drivers/net/slip.h | ||
82 | STRIP_MAGIC 0x5303 strip drivers/net/strip.c | ||
83 | X25_ASY_MAGIC 0x5303 x25_asy drivers/net/x25_asy.h | ||
84 | SIXPACK_MAGIC 0x5304 sixpack drivers/net/hamradio/6pack.h | ||
85 | AX25_MAGIC 0x5316 ax_disp drivers/net/mkiss.h | ||
86 | ESP_MAGIC 0x53ee esp_struct drivers/char/esp.h | ||
87 | TTY_MAGIC 0x5401 tty_struct include/linux/tty.h | ||
88 | MGSL_MAGIC 0x5401 mgsl_info drivers/char/synclink.c | ||
89 | TTY_DRIVER_MAGIC 0x5402 tty_driver include/linux/tty_driver.h | ||
90 | MGSLPC_MAGIC 0x5402 mgslpc_info drivers/char/pcmcia/synclink_cs.c | ||
91 | TTY_LDISC_MAGIC 0x5403 tty_ldisc include/linux/tty_ldisc.h | ||
92 | USB_SERIAL_MAGIC 0x6702 usb_serial drivers/usb/serial/usb-serial.h | ||
93 | FULL_DUPLEX_MAGIC 0x6969 drivers/net/tulip/de2104x.c | ||
94 | USB_BLUETOOTH_MAGIC 0x6d02 usb_bluetooth drivers/usb/class/bluetty.c | ||
95 | RFCOMM_TTY_MAGIC 0x6d02 net/bluetooth/rfcomm/tty.c | ||
96 | USB_SERIAL_PORT_MAGIC 0x7301 usb_serial_port drivers/usb/serial/usb-serial.h | ||
97 | CG_MAGIC 0x00090255 ufs_cylinder_group include/linux/ufs_fs.h | ||
98 | A2232_MAGIC 0x000a2232 gs_port drivers/char/ser_a2232.h | ||
99 | SOLARIS_SOCKET_MAGIC 0x000ADDED sol_socket_struct arch/sparc64/solaris/socksys.h | ||
100 | RPORT_MAGIC 0x00525001 r_port drivers/char/rocket_int.h | ||
101 | LSEMAGIC 0x05091998 lse drivers/fc4/fc.c | ||
102 | GDTIOCTL_MAGIC 0x06030f07 gdth_iowr_str drivers/scsi/gdth_ioctl.h | ||
103 | RIEBL_MAGIC 0x09051990 drivers/net/atarilance.c | ||
104 | RIO_MAGIC 0x12345678 gs_port drivers/char/rio/rio_linux.c | ||
105 | SX_MAGIC 0x12345678 gs_port drivers/char/sx.h | ||
106 | NBD_REQUEST_MAGIC 0x12560953 nbd_request include/linux/nbd.h | ||
107 | RED_MAGIC2 0x170fc2a5 (any) mm/slab.c | ||
108 | BAYCOM_MAGIC 0x19730510 baycom_state drivers/net/baycom_epp.c | ||
109 | ISDN_X25IFACE_MAGIC 0x1e75a2b9 isdn_x25iface_proto_data | ||
110 | drivers/isdn/isdn_x25iface.h | ||
111 | ECP_MAGIC 0x21504345 cdkecpsig include/linux/cdk.h | ||
112 | LSOMAGIC 0x27091997 lso drivers/fc4/fc.c | ||
113 | LSMAGIC 0x2a3b4d2a ls drivers/fc4/fc.c | ||
114 | WANPIPE_MAGIC 0x414C4453 sdla_{dump,exec} include/linux/wanpipe.h | ||
115 | CS_CARD_MAGIC 0x43525553 cs_card sound/oss/cs46xx.c | ||
116 | LABELCL_MAGIC 0x4857434c labelcl_info_s include/asm/ia64/sn/labelcl.h | ||
117 | ISDN_ASYNC_MAGIC 0x49344C01 modem_info include/linux/isdn.h | ||
118 | CTC_ASYNC_MAGIC 0x49344C01 ctc_tty_info drivers/s390/net/ctctty.c | ||
119 | ISDN_NET_MAGIC 0x49344C02 isdn_net_local_s drivers/isdn/i4l/isdn_net_lib.h | ||
120 | SAVEKMSG_MAGIC2 0x4B4D5347 savekmsg arch/*/amiga/config.c | ||
121 | STLI_BOARDMAGIC 0x4bc6c825 stlibrd include/linux/istallion.h | ||
122 | CS_STATE_MAGIC 0x4c4f4749 cs_state sound/oss/cs46xx.c | ||
123 | SLAB_C_MAGIC 0x4f17a36d kmem_cache_s mm/slab.c | ||
124 | COW_MAGIC 0x4f4f4f4d cow_header_v1 arch/um/drivers/ubd_user.c | ||
125 | I810_CARD_MAGIC 0x5072696E i810_card sound/oss/i810_audio.c | ||
126 | TRIDENT_CARD_MAGIC 0x5072696E trident_card sound/oss/trident.c | ||
127 | ROUTER_MAGIC 0x524d4157 wan_device include/linux/wanrouter.h | ||
128 | SCC_MAGIC 0x52696368 gs_port drivers/char/scc.h | ||
129 | SAVEKMSG_MAGIC1 0x53415645 savekmsg arch/*/amiga/config.c | ||
130 | GDA_MAGIC 0x58464552 gda include/asm-mips64/sn/gda.h | ||
131 | RED_MAGIC1 0x5a2cf071 (any) mm/slab.c | ||
132 | STL_PORTMAGIC 0x5a7182c9 stlport include/linux/stallion.h | ||
133 | EEPROM_MAGIC_VALUE 0X5ab478d2 lanai_dev drivers/atm/lanai.c | ||
134 | HDLCDRV_MAGIC 0x5ac6e778 hdlcdrv_state include/linux/hdlcdrv.h | ||
135 | EPCA_MAGIC 0x5c6df104 channel include/linux/epca.h | ||
136 | PCXX_MAGIC 0x5c6df104 channel drivers/char/pcxx.h | ||
137 | KV_MAGIC 0x5f4b565f kernel_vars_s include/asm-mips64/sn/klkernvars.h | ||
138 | I810_STATE_MAGIC 0x63657373 i810_state sound/oss/i810_audio.c | ||
139 | TRIDENT_STATE_MAGIC 0x63657373 trient_state sound/oss/trident.c | ||
140 | M3_CARD_MAGIC 0x646e6f50 m3_card sound/oss/maestro3.c | ||
141 | FW_HEADER_MAGIC 0x65726F66 fw_header drivers/atm/fore200e.h | ||
142 | SLOT_MAGIC 0x67267321 slot drivers/hotplug/cpqphp.h | ||
143 | SLOT_MAGIC 0x67267322 slot drivers/hotplug/acpiphp.h | ||
144 | LO_MAGIC 0x68797548 nbd_device include/linux/nbd.h | ||
145 | OPROFILE_MAGIC 0x6f70726f super_block drivers/oprofile/oprofilefs.h | ||
146 | M3_STATE_MAGIC 0x734d724d m3_state sound/oss/maestro3.c | ||
147 | STL_PANELMAGIC 0x7ef621a1 stlpanel include/linux/stallion.h | ||
148 | VMALLOC_MAGIC 0x87654320 snd_alloc_track sound/core/memory.c | ||
149 | KMALLOC_MAGIC 0x87654321 snd_alloc_track sound/core/memory.c | ||
150 | PWC_MAGIC 0x89DC10AB pwc_device drivers/usb/media/pwc.h | ||
151 | NBD_REPLY_MAGIC 0x96744668 nbd_reply include/linux/nbd.h | ||
152 | STL_BOARDMAGIC 0xa2267f52 stlbrd include/linux/stallion.h | ||
153 | ENI155_MAGIC 0xa54b872d midway_eprom drivers/atm/eni.h | ||
154 | SCI_MAGIC 0xbabeface gs_port drivers/char/sh-sci.h | ||
155 | CODA_MAGIC 0xC0DAC0DA coda_file_info include/linux/coda_fs_i.h | ||
156 | DPMEM_MAGIC 0xc0ffee11 gdt_pci_sram drivers/scsi/gdth.h | ||
157 | STLI_PORTMAGIC 0xe671c7a1 stliport include/linux/istallion.h | ||
158 | YAM_MAGIC 0xF10A7654 yam_port drivers/net/hamradio/yam.c | ||
159 | CCB_MAGIC 0xf2691ad2 ccb drivers/scsi/ncr53c8xx.c | ||
160 | QUEUE_MAGIC_FREE 0xf7e1c9a3 queue_entry drivers/scsi/arm/queue.c | ||
161 | QUEUE_MAGIC_USED 0xf7e1cc33 queue_entry drivers/scsi/arm/queue.c | ||
162 | HTB_CMAGIC 0xFEFAFEF1 htb_class net/sched/sch_htb.c | ||
163 | NMI_MAGIC 0x48414d4d455201 nmi_s include/asm-mips64/sn/nmi.h | ||
164 | |||
165 | Note that there are also defined special per-driver magic numbers in sound | ||
166 | memory management. See include/sound/sndmagic.h for complete list of them. Many | ||
167 | OSS sound drivers have their magic numbers constructed from the soundcard PCI | ||
168 | ID - these are not listed here as well. | ||
169 | |||
170 | IrDA subsystem also uses large number of own magic numbers, see | ||
171 | include/net/irda/irda.h for a complete list of them. | ||
172 | |||
173 | HFS is another larger user of magic numbers - you can find them in | ||
174 | fs/hfs/hfs.h. | ||