/* 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 #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 int openct[NR_DEVS]; static ssize_t m_char_read(devminor_t minor, u64_t position, endpoint_t endpt, cp_grant_id_t grant, size_t size, int flags, cdev_id_t id); static ssize_t m_char_write(devminor_t minor, u64_t position, endpoint_t endpt, cp_grant_id_t grant, size_t size, int flags, cdev_id_t id); static int m_char_open(devminor_t minor, int access, endpoint_t user_endpt); static int m_char_close(devminor_t minor); static struct device *m_block_part(devminor_t minor); static ssize_t m_block_transfer(devminor_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(devminor_t minor, int access); static int m_block_close(devminor_t minor); static int m_block_ioctl(devminor_t minor, unsigned long request, endpoint_t endpt, cp_grant_id_t grant, endpoint_t user_endpt); /* Entry points to the CHARACTER part of this driver. */ static struct chardriver m_cdtab = { .cdr_open = m_char_open, /* open device */ .cdr_close = m_char_close, /* close device */ .cdr_read = m_char_read, /* read from device */ .cdr_write = m_char_write /* write to device */ }; /* Entry points to the BLOCK part of this driver. */ static struct blockdriver m_bdtab = { .bdr_type = BLOCKDRIVER_TYPE_DISK,/* handle partition requests */ .bdr_open = m_block_open, /* open device */ .bdr_close = m_block_close, /* nothing on a close */ .bdr_transfer = m_block_transfer, /* do the I/O */ .bdr_ioctl = m_block_ioctl, /* ram disk I/O control */ .bdr_part = m_block_part /* return partition information */ }; /* 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, &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 = kinfo.kmem_base; m_geom[KMEM_DEV].dv_size = 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= 0; m_geom[IMGRD_DEV].dv_size= imgrd_size; m_vaddrs[IMGRD_DEV] = (vir_bytes) imgrd; for(i = 0; i < NR_DEVS; i++) openct[i] = 0; /* Set up memory range for /dev/mem. */ m_geom[MEM_DEV].dv_base = 0; m_geom[MEM_DEV].dv_size = 0xffffffffULL; m_vaddrs[MEM_DEV] = (vir_bytes) MAP_FAILED; /* we are not mapping this in. */ return(OK); } /*===========================================================================* * m_is_block * *===========================================================================*/ static int m_is_block(devminor_t minor) { /* Return TRUE iff the given minor device number is for a block device. */ switch (minor) { case MEM_DEV: case KMEM_DEV: case NULL_DEV: case ZERO_DEV: return FALSE; default: return TRUE; } } /*===========================================================================* * m_transfer_kmem * *===========================================================================*/ static ssize_t m_transfer_kmem(devminor_t minor, int do_write, u64_t position, endpoint_t endpt, cp_grant_id_t grant, size_t size) { /* Transfer from or to the KMEM device. */ u64_t dv_size, dev_vaddr; int r; dv_size = m_geom[minor].dv_size; dev_vaddr = m_vaddrs[minor]; if (!dev_vaddr || dev_vaddr == (vir_bytes) MAP_FAILED) { printf("MEM: dev %d not initialized\n", minor); return EIO; } if (position >= dv_size) return 0; /* check for EOF */ if (position + size > dv_size) size = dv_size - position; if (!do_write) /* copy actual data */ r = sys_safecopyto(endpt, grant, 0, dev_vaddr + position, size); else r = sys_safecopyfrom(endpt, grant, 0, dev_vaddr + position, size); return (r != OK) ? r : size; } /*===========================================================================* * m_transfer_mem * *===========================================================================*/ static ssize_t m_transfer_mem(devminor_t minor, int do_write, u64_t position, endpoint_t endpt, cp_grant_id_t grant, size_t size) { /* Transfer from or to the MEM device. */ static int any_mapped = 0; static phys_bytes pagestart_mapped; static char *vaddr; phys_bytes mem_phys, pagestart; size_t off, page_off, subcount; u64_t dv_size; int r; dv_size = m_geom[minor].dv_size; if (position >= dv_size) return 0; /* check for EOF */ if (position + size > dv_size) size = dv_size - position; /* Physical copying. Only used to access entire memory. * Transfer one 'page window' at a time. */ off = 0; while (off < size) { mem_phys = (phys_bytes) position; page_off = (size_t) (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) { printf("memory: vm_map_phys failed\n"); return ENOMEM; } any_mapped = 1; pagestart_mapped = pagestart; } /* how much to be done within this page. */ subcount = PAGE_SIZE - page_off; if (subcount > size) subcount = size; if (!do_write) /* copy data */ r = sys_safecopyto(endpt, grant, off, (vir_bytes) vaddr + page_off, subcount); else r = sys_safecopyfrom(endpt, grant, off, (vir_bytes) vaddr + page_off, subcount); if (r != OK) return r; position += subcount; off += subcount; } return off; } /*===========================================================================* * m_char_read * *===========================================================================*/ static ssize_t m_char_read(devminor_t minor, u64_t position, endpoint_t endpt, cp_grant_id_t grant, size_t size, int UNUSED(flags), cdev_id_t UNUSED(id)) { /* Read from one of the driver's character devices. */ ssize_t r; /* Check if the minor device number is ok. */ if (minor < 0 || minor >= NR_DEVS || m_is_block(minor)) return ENXIO; switch (minor) { case NULL_DEV: r = 0; /* always at EOF */ break; case ZERO_DEV: /* Fill the target area with zeroes. In fact, let the kernel do it! */ if ((r = sys_safememset(endpt, grant, 0, '\0', size)) == OK) r = size; break; case KMEM_DEV: r = m_transfer_kmem(minor, FALSE, position, endpt, grant, size); break; case MEM_DEV: r = m_transfer_mem(minor, FALSE, position, endpt, grant, size); break; default: panic("unknown character device %d", minor); } return r; } /*===========================================================================* * m_char_write * *===========================================================================*/ static ssize_t m_char_write(devminor_t minor, u64_t position, endpoint_t endpt, cp_grant_id_t grant, size_t size, int UNUSED(flags), cdev_id_t UNUSED(id)) { /* Write to one of the driver's character devices. */ ssize_t r; /* Check if the minor device number is ok. */ if (minor < 0 || minor >= NR_DEVS || m_is_block(minor)) return ENXIO; switch (minor) { case NULL_DEV: case ZERO_DEV: r = size; /* just eat everything */ break; case KMEM_DEV: r = m_transfer_kmem(minor, TRUE, position, endpt, grant, size); break; case MEM_DEV: r = m_transfer_mem(minor, TRUE, position, endpt, grant, size); break; default: panic("unknown character device %d", minor); } return r; } /*===========================================================================* * m_char_open * *===========================================================================*/ static int m_char_open(devminor_t minor, int access, endpoint_t user_endpt) { /* Open a memory character device. */ /* Check if the minor device number is ok. */ if (minor < 0 || minor >= NR_DEVS || m_is_block(minor)) return ENXIO; #if defined(__i386__) if (minor == MEM_DEV) { int r = sys_enable_iop(user_endpt); if (r != OK) { printf("m_char_open: sys_enable_iop failed for %d: %d\n", user_endpt, r); return r; } } #endif openct[minor]++; return(OK); } /*===========================================================================* * m_char_close * *===========================================================================*/ static int m_char_close(devminor_t minor) { /* Close a memory character device. */ if (minor < 0 || minor >= NR_DEVS || m_is_block(minor)) return ENXIO; if(openct[minor] < 1) { printf("MEMORY: closing unopened device %d\n", minor); return(EINVAL); } openct[minor]--; return(OK); } /*===========================================================================* * m_block_part * *===========================================================================*/ static struct device *m_block_part(devminor_t minor) { /* Prepare for I/O on a device: check if the minor device number is ok. */ if (minor < 0 || minor >= NR_DEVS || !m_is_block(minor)) return(NULL); return(&m_geom[minor]); } /*===========================================================================* * m_block_transfer * *===========================================================================*/ static int m_block_transfer( devminor_t minor, /* minor device number */ int do_write, /* read or write? */ u64_t position, /* 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; u64_t dv_size; int r; 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 = dv->dv_size; dev_vaddr = m_vaddrs[minor]; if (ex64hi(position) != 0) return OK; /* Beyond EOF */ 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(devminor_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(devminor_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(devminor_t minor, unsigned long request, endpoint_t endpt, cp_grant_id_t grant, endpoint_t UNUSED(user_endpt)) { /* 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] && dv->dv_size == (u64_t) 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 = 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 = 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 = ramdev_size; return(OK); }