/* This file contains the device dependent part of the drivers for the * following special files: * /dev/ram - RAM disk * /dev/mem - absolute memory * /dev/kmem - kernel virtual memory * /dev/null - null device (data sink) * /dev/boot - boot device loaded from boot image * /dev/zero - null byte stream generator * /dev/imgrd - boot image RAM disk * * Changes: * Apr 29, 2005 added null byte generator (Jorrit N. Herder) * Apr 09, 2005 added support for boot device (Jorrit N. Herder) * Jul 26, 2004 moved RAM driver to user-space (Jorrit N. Herder) * Apr 20, 1992 device dependent/independent split (Kees J. Bot) */ #include #include #include #include #include #include #include #include #include #include "kernel/const.h" #include "kernel/config.h" #include "kernel/type.h" #include #include "local.h" /* ramdisks (/dev/ram*) */ #define RAMDISKS 6 #define RAM_DEV_LAST (RAM_DEV_FIRST+RAMDISKS-1) #define NR_DEVS (7+RAMDISKS) /* number of minor devices */ static struct device m_geom[NR_DEVS]; /* base and size of each device */ static vir_bytes m_vaddrs[NR_DEVS]; static dev_t m_device; /* current minor character device */ static int openct[NR_DEVS]; static struct device *m_prepare(dev_t device); static int m_transfer(endpoint_t endpt, int opcode, u64_t position, iovec_t *iov, unsigned int nr_req, endpoint_t user_endpt, unsigned int flags); static int m_do_open(message *m_ptr); static int m_do_close(message *m_ptr); static struct device *m_block_part(dev_t minor); static int m_block_transfer(dev_t minor, int do_write, u64_t position, endpoint_t endpt, iovec_t *iov, unsigned int nr_req, int flags); static int m_block_open(dev_t minor, int access); static int m_block_close(dev_t minor); static int m_block_ioctl(dev_t minor, unsigned int request, endpoint_t endpt, cp_grant_id_t grant); /* Entry points to the CHARACTER part of this driver. */ static struct chardriver m_cdtab = { m_do_open, /* open or mount */ m_do_close, /* nothing on a close */ nop_ioctl, /* no I/O control */ m_prepare, /* prepare for I/O on a given minor device */ m_transfer, /* do the I/O */ nop_cleanup, /* no need to clean up */ nop_alarm, /* no alarms */ nop_cancel, /* no blocking operations */ nop_select, /* select not supported */ NULL /* other messages not supported */ }; /* Entry points to the BLOCK part of this driver. */ static struct blockdriver m_bdtab = { BLOCKDRIVER_TYPE_DISK,/* handle partition requests */ m_block_open, /* open or mount */ m_block_close, /* nothing on a close */ m_block_transfer, /* do the I/O */ m_block_ioctl, /* ram disk I/O control */ NULL, /* no need to clean up */ m_block_part, /* return partition information */ NULL, /* no geometry */ NULL, /* no interrupt processing */ NULL, /* no alarm processing */ NULL, /* no processing of other messages */ NULL /* no threading support */ }; /* Buffer for the /dev/zero null byte feed. */ #define ZERO_BUF_SIZE 1024 static char dev_zero[ZERO_BUF_SIZE]; #define click_to_round_k(n) \ ((unsigned) ((((unsigned long) (n) << CLICK_SHIFT) + 512) / 1024)) /* SEF functions and variables. */ static void sef_local_startup(void); static int sef_cb_init_fresh(int type, sef_init_info_t *info); /*===========================================================================* * main * *===========================================================================*/ int main(void) { message msg; int r, ipc_status; /* SEF local startup. */ sef_local_startup(); /* The receive loop. */ for (;;) { if ((r = driver_receive(ANY, &msg, &ipc_status)) != OK) panic("memory: driver_receive failed (%d)", r); if (IS_BDEV_RQ(msg.m_type)) blockdriver_process(&m_bdtab, &msg, ipc_status); else chardriver_process(&m_cdtab, CHARDRIVER_SYNC, &msg, ipc_status); } return(OK); } /*===========================================================================* * sef_local_startup * *===========================================================================*/ static void sef_local_startup() { /* Register init callbacks. */ sef_setcb_init_fresh(sef_cb_init_fresh); sef_setcb_init_lu(sef_cb_init_fresh); sef_setcb_init_restart(sef_cb_init_fresh); /* Register live update callbacks. */ sef_setcb_lu_prepare(sef_cb_lu_prepare_always_ready); sef_setcb_lu_state_isvalid(sef_cb_lu_state_isvalid_standard); /* Let SEF perform startup. */ sef_startup(); } /*===========================================================================* * sef_cb_init_fresh * *===========================================================================*/ static int sef_cb_init_fresh(int UNUSED(type), sef_init_info_t *UNUSED(info)) { /* Initialize the memory driver. */ int i; #if 0 struct kinfo kinfo; /* kernel information */ int s; if (OK != (s=sys_getkinfo(&kinfo))) { panic("Couldn't get kernel information: %d", s); } /* Map in kernel memory for /dev/kmem. */ m_geom[KMEM_DEV].dv_base = cvul64(kinfo.kmem_base); m_geom[KMEM_DEV].dv_size = cvul64(kinfo.kmem_size); if((m_vaddrs[KMEM_DEV] = vm_map_phys(SELF, (void *) kinfo.kmem_base, kinfo.kmem_size)) == MAP_FAILED) { printf("MEM: Couldn't map in /dev/kmem."); } #endif /* Ramdisk image built into the memory driver */ m_geom[IMGRD_DEV].dv_base= cvul64(0); m_geom[IMGRD_DEV].dv_size= cvul64(imgrd_size); m_vaddrs[IMGRD_DEV] = (vir_bytes) imgrd; /* Initialize /dev/zero. Simply write zeros into the buffer. */ for (i=0; i= NR_DEVS || m_is_block(device)) return(NULL); m_device = device; return(&m_geom[device]); } /*===========================================================================* * m_transfer * *===========================================================================*/ static int m_transfer( endpoint_t endpt, /* endpoint of grant owner */ int opcode, /* DEV_GATHER_S or DEV_SCATTER_S */ u64_t pos64, /* offset on device to read or write */ iovec_t *iov, /* pointer to read or write request vector */ unsigned int nr_req, /* length of request vector */ endpoint_t UNUSED(user_endpt),/* endpoint of user process */ unsigned int UNUSED(flags) ) { /* Read or write one the driver's character devices. */ unsigned count, left, chunk; vir_bytes vir_offset = 0; struct device *dv; unsigned long dv_size; int s, r; off_t position; cp_grant_id_t grant; vir_bytes dev_vaddr; /* ZERO_DEV and NULL_DEV are infinite in size. */ if (m_device != ZERO_DEV && m_device != NULL_DEV && ex64hi(pos64) != 0) return OK; /* Beyond EOF */ position= cv64ul(pos64); /* Get minor device number and check for /dev/null. */ dv = &m_geom[m_device]; dv_size = cv64ul(dv->dv_size); dev_vaddr = m_vaddrs[m_device]; while (nr_req > 0) { /* How much to transfer and where to / from. */ count = iov->iov_size; grant = (cp_grant_id_t) iov->iov_addr; switch (m_device) { /* No copying; ignore request. */ case NULL_DEV: if (opcode == DEV_GATHER_S) return(OK); /* always at EOF */ break; /* Virtual copying. For kernel memory. */ default: case KMEM_DEV: if(!dev_vaddr || dev_vaddr == (vir_bytes) MAP_FAILED) { printf("MEM: dev %d not initialized\n", m_device); return EIO; } if (position >= dv_size) return(OK); /* check for EOF */ if (position + count > dv_size) count = dv_size - position; if (opcode == DEV_GATHER_S) { /* copy actual data */ r=sys_safecopyto(endpt, grant, vir_offset, dev_vaddr + position, count); } else { r=sys_safecopyfrom(endpt, grant, vir_offset, dev_vaddr + position, count); } if(r != OK) { panic("I/O copy failed: %d", r); } break; /* Physical copying. Only used to access entire memory. * Transfer one 'page window' at a time. */ case MEM_DEV: { u32_t pagestart, page_off; static u32_t pagestart_mapped; static int any_mapped = 0; static char *vaddr; int r; u32_t subcount; phys_bytes mem_phys; if (position >= dv_size) return(OK); /* check for EOF */ if (position + count > dv_size) count = dv_size - position; mem_phys = position; page_off = mem_phys % PAGE_SIZE; pagestart = mem_phys - page_off; /* All memory to the map call has to be page-aligned. * Don't have to map same page over and over. */ if(!any_mapped || pagestart_mapped != pagestart) { if(any_mapped) { if(vm_unmap_phys(SELF, vaddr, PAGE_SIZE) != OK) panic("vm_unmap_phys failed"); any_mapped = 0; } vaddr = vm_map_phys(SELF, (void *) pagestart, PAGE_SIZE); if(vaddr == MAP_FAILED) r = ENOMEM; else r = OK; if(r != OK) { printf("memory: vm_map_phys failed\n"); return r; } any_mapped = 1; pagestart_mapped = pagestart; } /* how much to be done within this page. */ subcount = PAGE_SIZE-page_off; if(subcount > count) subcount = count; if (opcode == DEV_GATHER_S) { /* copy data */ s=sys_safecopyto(endpt, grant, vir_offset, (vir_bytes) vaddr+page_off, subcount); } else { s=sys_safecopyfrom(endpt, grant, vir_offset, (vir_bytes) vaddr+page_off, subcount); } if(s != OK) return s; count = subcount; break; } /* Null byte stream generator. */ case ZERO_DEV: if (opcode == DEV_GATHER_S) { size_t suboffset = 0; left = count; while (left > 0) { chunk = (left > ZERO_BUF_SIZE) ? ZERO_BUF_SIZE : left; s=sys_safecopyto(endpt, grant, vir_offset+suboffset, (vir_bytes) dev_zero, chunk); if(s != OK) return s; left -= chunk; suboffset += chunk; } } break; } /* Book the number of bytes transferred. */ position += count; vir_offset += count; if ((iov->iov_size -= count) == 0) { iov++; nr_req--; vir_offset = 0; } } return(OK); } /*===========================================================================* * m_do_open * *===========================================================================*/ static int m_do_open(message *m_ptr) { /* Open a memory character device. */ int r; /* Check device number on open. */ if (m_prepare(m_ptr->DEVICE) == NULL) return(ENXIO); #if defined(__i386__) if (m_device == MEM_DEV) { r = sys_enable_iop(m_ptr->USER_ENDPT); if (r != OK) { printf("m_do_open: sys_enable_iop failed for %d: %d\n", m_ptr->USER_ENDPT, r); return r; } } #endif openct[m_device]++; return(OK); } /*===========================================================================* * m_do_close * *===========================================================================*/ static int m_do_close(message *m_ptr) { /* Close a memory character device. */ if (m_prepare(m_ptr->DEVICE) == NULL) return(ENXIO); if(openct[m_device] < 1) { printf("MEMORY: closing unopened device %d\n", m_device); return(EINVAL); } openct[m_device]--; return(OK); } /*===========================================================================* * m_block_part * *===========================================================================*/ static struct device *m_block_part(dev_t minor) { /* Prepare for I/O on a device: check if the minor device number is ok. */ if (minor >= NR_DEVS || !m_is_block(minor)) return(NULL); return(&m_geom[minor]); } /*===========================================================================* * m_block_transfer * *===========================================================================*/ static int m_block_transfer( dev_t minor, /* minor device number */ int do_write, /* read or write? */ u64_t pos64, /* offset on device to read or write */ endpoint_t endpt, /* process doing the request */ iovec_t *iov, /* pointer to read or write request vector */ unsigned int nr_req, /* length of request vector */ int UNUSED(flags) /* transfer flags */ ) { /* Read or write one the driver's block devices. */ unsigned count; vir_bytes vir_offset = 0; struct device *dv; unsigned long dv_size; int r; off_t position; vir_bytes dev_vaddr; cp_grant_id_t grant; ssize_t total = 0; /* Get minor device information. */ if ((dv = m_block_part(minor)) == NULL) return(ENXIO); dv_size = cv64ul(dv->dv_size); dev_vaddr = m_vaddrs[minor]; if (ex64hi(pos64) != 0) return OK; /* Beyond EOF */ position= cv64ul(pos64); while (nr_req > 0) { /* How much to transfer and where to / from. */ count = iov->iov_size; grant = (cp_grant_id_t) iov->iov_addr; /* Virtual copying. For RAM disks and internal FS. */ if(!dev_vaddr || dev_vaddr == (vir_bytes) MAP_FAILED) { printf("MEM: dev %d not initialized\n", minor); return EIO; } if (position >= dv_size) return(total); /* check for EOF */ if (position + count > dv_size) count = dv_size - position; if (!do_write) { /* copy actual data */ r=sys_safecopyto(endpt, grant, vir_offset, dev_vaddr + position, count); } else { r=sys_safecopyfrom(endpt, grant, vir_offset, dev_vaddr + position, count); } if(r != OK) { panic("I/O copy failed: %d", r); } /* Book the number of bytes transferred. */ position += count; vir_offset += count; total += count; if ((iov->iov_size -= count) == 0) { iov++; nr_req--; vir_offset = 0; } } return(total); } /*===========================================================================* * m_block_open * *===========================================================================*/ static int m_block_open(dev_t minor, int UNUSED(access)) { /* Open a memory block device. */ if (m_block_part(minor) == NULL) return(ENXIO); openct[minor]++; return(OK); } /*===========================================================================* * m_block_close * *===========================================================================*/ static int m_block_close(dev_t minor) { /* Close a memory block device. */ if (m_block_part(minor) == NULL) return(ENXIO); if(openct[minor] < 1) { printf("MEMORY: closing unopened device %d\n", minor); return(EINVAL); } openct[minor]--; return(OK); } /*===========================================================================* * m_block_ioctl * *===========================================================================*/ static int m_block_ioctl(dev_t minor, unsigned int request, endpoint_t endpt, cp_grant_id_t grant) { /* I/O controls for the block devices of the memory driver. Currently there is * one I/O control specific to the memory driver: * - MIOCRAMSIZE: to set the size of the RAM disk. */ struct device *dv; u32_t ramdev_size; int s; void *mem; int is_imgrd = 0; if (request != MIOCRAMSIZE) return EINVAL; if(minor == IMGRD_DEV) is_imgrd = 1; /* Someone wants to create a new RAM disk with the given size. * A ramdisk can be created only once, and only on RAM disk device. */ if ((dv = m_block_part(minor)) == NULL) return ENXIO; if((minor < RAM_DEV_FIRST || minor > RAM_DEV_LAST) && minor != RAM_DEV_OLD && !is_imgrd) { printf("MEM: MIOCRAMSIZE: %d not a ramdisk\n", minor); return EINVAL; } /* Get request structure */ s= sys_safecopyfrom(endpt, grant, 0, (vir_bytes)&ramdev_size, sizeof(ramdev_size)); if (s != OK) return s; if(is_imgrd) ramdev_size = 0; if(m_vaddrs[minor] && !cmp64(dv->dv_size, cvul64(ramdev_size))) { return(OK); } /* openct is 1 for the ioctl(). */ if(openct[minor] != 1) { printf("MEM: MIOCRAMSIZE: %d in use (count %d)\n", minor, openct[minor]); return(EBUSY); } if(m_vaddrs[minor]) { u32_t a, o; u64_t size; int r; if(ex64hi(dv->dv_size)) { panic("huge old ramdisk"); } size = dv->dv_size; a = m_vaddrs[minor]; if((o = a % PAGE_SIZE)) { vir_bytes l = PAGE_SIZE - o; a += l; size -= l; } size = rounddown(size, PAGE_SIZE); r = minix_munmap((void *) a, size); if(r != OK) { printf("memory: WARNING: munmap failed: %d\n", r); } m_vaddrs[minor] = (vir_bytes) NULL; dv->dv_size = 0; } #if DEBUG printf("MEM:%d: allocating ramdisk of size 0x%x\n", minor, ramdev_size); #endif mem = NULL; /* Try to allocate a piece of memory for the RAM disk. */ if(ramdev_size > 0 && (mem = minix_mmap(NULL, ramdev_size, PROT_READ|PROT_WRITE, MAP_PREALLOC|MAP_ANON, -1, 0)) == MAP_FAILED) { printf("MEM: failed to get memory for ramdisk\n"); return(ENOMEM); } m_vaddrs[minor] = (vir_bytes) mem; dv->dv_size = cvul64(ramdev_size); return(OK); }