cregit-Linux how code gets into the kernel

Release 4.11 block/ioctl.c

Directory: block
#include <linux/capability.h>
#include <linux/blkdev.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <linux/blkpg.h>
#include <linux/hdreg.h>
#include <linux/backing-dev.h>
#include <linux/fs.h>
#include <linux/blktrace_api.h>
#include <linux/pr.h>
#include <linux/uaccess.h>


static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) { struct block_device *bdevp; struct gendisk *disk; struct hd_struct *part, *lpart; struct blkpg_ioctl_arg a; struct blkpg_partition p; struct disk_part_iter piter; long long start, length; int partno; if (!capable(CAP_SYS_ADMIN)) return -EACCES; if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg))) return -EFAULT; if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition))) return -EFAULT; disk = bdev->bd_disk; if (bdev != bdev->bd_contains) return -EINVAL; partno = p.pno; if (partno <= 0) return -EINVAL; switch (a.op) { case BLKPG_ADD_PARTITION: start = p.start >> 9; length = p.length >> 9; /* check for fit in a hd_struct */ if (sizeof(sector_t) == sizeof(long) && sizeof(long long) > sizeof(long)) { long pstart = start, plength = length; if (pstart != start || plength != length || pstart < 0 || plength < 0 || partno > 65535) return -EINVAL; } /* check if partition is aligned to blocksize */ if (p.start & (bdev_logical_block_size(bdev) - 1)) return -EINVAL; mutex_lock(&bdev->bd_mutex); /* overlap? */ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); while ((part = disk_part_iter_next(&piter))) { if (!(start + length <= part->start_sect || start >= part->start_sect + part->nr_sects)) { disk_part_iter_exit(&piter); mutex_unlock(&bdev->bd_mutex); return -EBUSY; } } disk_part_iter_exit(&piter); /* all seems OK */ part = add_partition(disk, partno, start, length, ADDPART_FLAG_NONE, NULL); mutex_unlock(&bdev->bd_mutex); return PTR_ERR_OR_ZERO(part); case BLKPG_DEL_PARTITION: part = disk_get_part(disk, partno); if (!part) return -ENXIO; bdevp = bdget(part_devt(part)); disk_put_part(part); if (!bdevp) return -ENOMEM; mutex_lock(&bdevp->bd_mutex); if (bdevp->bd_openers) { mutex_unlock(&bdevp->bd_mutex); bdput(bdevp); return -EBUSY; } /* all seems OK */ fsync_bdev(bdevp); invalidate_bdev(bdevp); mutex_lock_nested(&bdev->bd_mutex, 1); delete_partition(disk, partno); mutex_unlock(&bdev->bd_mutex); mutex_unlock(&bdevp->bd_mutex); bdput(bdevp); return 0; case BLKPG_RESIZE_PARTITION: start = p.start >> 9; /* new length of partition in bytes */ length = p.length >> 9; /* check for fit in a hd_struct */ if (sizeof(sector_t) == sizeof(long) && sizeof(long long) > sizeof(long)) { long pstart = start, plength = length; if (pstart != start || plength != length || pstart < 0 || plength < 0) return -EINVAL; } part = disk_get_part(disk, partno); if (!part) return -ENXIO; bdevp = bdget(part_devt(part)); if (!bdevp) { disk_put_part(part); return -ENOMEM; } mutex_lock(&bdevp->bd_mutex); mutex_lock_nested(&bdev->bd_mutex, 1); if (start != part->start_sect) { mutex_unlock(&bdevp->bd_mutex); mutex_unlock(&bdev->bd_mutex); bdput(bdevp); disk_put_part(part); return -EINVAL; } /* overlap? */ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); while ((lpart = disk_part_iter_next(&piter))) { if (lpart->partno != partno && !(start + length <= lpart->start_sect || start >= lpart->start_sect + lpart->nr_sects) ) { disk_part_iter_exit(&piter); mutex_unlock(&bdevp->bd_mutex); mutex_unlock(&bdev->bd_mutex); bdput(bdevp); disk_put_part(part); return -EBUSY; } } disk_part_iter_exit(&piter); part_nr_sects_write(part, (sector_t)length); i_size_write(bdevp->bd_inode, p.length); mutex_unlock(&bdevp->bd_mutex); mutex_unlock(&bdev->bd_mutex); bdput(bdevp); disk_put_part(part); return 0; default: return -EINVAL; } }

Contributors

PersonTokensPropCommitsCommitProp
Vivek Goyal33039.86%13.45%
Al Viro27232.85%1034.48%
Linus Torvalds (pre-git)769.18%13.45%
Tejun Heo728.70%413.79%
Stefan Haberland202.42%13.45%
Andrew Morton192.29%26.90%
Arjan van de Ven141.69%13.45%
Linus Torvalds60.72%13.45%
Richard Gooch50.60%13.45%
Alan Cox40.48%13.45%
Peter Zijlstra40.48%26.90%
Will Drewry20.24%13.45%
Fabio Massimo Di Nitto20.24%13.45%
Abdel Benamrouche10.12%13.45%
Duan Jiong10.12%13.45%
Total828100.00%29100.00%

/* * This is an exported API for the block driver, and will not * acquire bd_mutex. This API should be used in case that * caller has held bd_mutex already. */
int __blkdev_reread_part(struct block_device *bdev) { struct gendisk *disk = bdev->bd_disk; if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains) return -EINVAL; if (!capable(CAP_SYS_ADMIN)) return -EACCES; lockdep_assert_held(&bdev->bd_mutex); return rescan_partitions(disk, bdev); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro2335.38%342.86%
Linus Torvalds (pre-git)2030.77%114.29%
Jarod Wilson1827.69%114.29%
Tejun Heo46.15%228.57%
Total65100.00%7100.00%

EXPORT_SYMBOL(__blkdev_reread_part); /* * This is an exported API for the block driver, and will * try to acquire bd_mutex. If bd_mutex has been held already * in current context, please call __blkdev_reread_part(). * * Make sure the held locks in current context aren't required * in open()/close() handler and I/O path for avoiding ABBA deadlock: * - bd_mutex is held before calling block driver's open/close * handler * - reading partition table may submit I/O to the block device */
int blkdev_reread_part(struct block_device *bdev) { int res; mutex_lock(&bdev->bd_mutex); res = __blkdev_reread_part(bdev); mutex_unlock(&bdev->bd_mutex); return res; }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro1435.90%120.00%
Jarod Wilson1333.33%120.00%
Linus Torvalds (pre-git)717.95%120.00%
Arjan van de Ven37.69%120.00%
Ming Lei25.13%120.00%
Total39100.00%5100.00%

EXPORT_SYMBOL(blkdev_reread_part);
static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, unsigned long arg, unsigned long flags) { uint64_t range[2]; uint64_t start, len; if (!(mode & FMODE_WRITE)) return -EBADF; if (copy_from_user(range, (void __user *)arg, sizeof(range))) return -EFAULT; start = range[0]; len = range[1]; if (start & 511) return -EINVAL; if (len & 511) return -EINVAL; start >>= 9; len >>= 9; if (start + len > (i_size_read(bdev->bd_inode) >> 9)) return -EINVAL; return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig7148.63%240.00%
David Woodhouse6645.21%120.00%
Adrian Hunter64.11%120.00%
Mike Snitzer32.05%120.00%
Total146100.00%5100.00%


static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, unsigned long arg) { uint64_t range[2]; struct address_space *mapping; uint64_t start, end, len; if (!(mode & FMODE_WRITE)) return -EBADF; if (copy_from_user(range, (void __user *)arg, sizeof(range))) return -EFAULT; start = range[0]; len = range[1]; end = start + len - 1; if (start & 511) return -EINVAL; if (len & 511) return -EINVAL; if (end >= (uint64_t)i_size_read(bdev->bd_inode)) return -EINVAL; if (end < start) return -EINVAL; /* Invalidate the page cache, including dirty pages */ mapping = bdev->bd_inode->i_mapping; truncate_inode_pages_range(mapping, start, end); return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, false); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig6637.08%125.00%
Martin K. Petersen6134.27%250.00%
Darrick J. Wong5128.65%125.00%
Total178100.00%4100.00%


static int put_ushort(unsigned long arg, unsigned short val) { return put_user(val, (unsigned short __user *)arg); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro2382.14%266.67%
Linus Torvalds (pre-git)517.86%133.33%
Total28100.00%3100.00%


static int put_int(unsigned long arg, int val) { return put_user(val, (int __user *)arg); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro2180.77%266.67%
Linus Torvalds (pre-git)519.23%133.33%
Total26100.00%3100.00%


static int put_uint(unsigned long arg, unsigned int val) { return put_user(val, (unsigned int __user *)arg); }

Contributors

PersonTokensPropCommitsCommitProp
Martin K. Petersen28100.00%1100.00%
Total28100.00%1100.00%


static int put_long(unsigned long arg, long val) { return put_user(val, (long __user *)arg); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro2388.46%266.67%
Linus Torvalds (pre-git)311.54%133.33%
Total26100.00%3100.00%


static int put_ulong(unsigned long arg, unsigned long val) { return put_user(val, (unsigned long __user *)arg); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro28100.00%2100.00%
Total28100.00%2100.00%


static int put_u64(unsigned long arg, u64 val) { return put_user(val, (u64 __user *)arg); }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro2596.15%266.67%
Linus Torvalds (pre-git)13.85%133.33%
Total26100.00%3100.00%


int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long arg) { struct gendisk *disk = bdev->bd_disk; if (disk->fops->ioctl) return disk->fops->ioctl(bdev, mode, cmd, arg); return -ENOTTY; }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro5596.49%375.00%
Linus Torvalds (pre-git)23.51%125.00%
Total57100.00%4100.00%

/* * For the record: _GPL here is only because somebody decided to slap it * on the previous export. Sheer idiocy, since it wasn't copyrightable * at all and could be open-coded without any exports by anybody who cares. */ EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
static int blkdev_pr_register(struct block_device *bdev, struct pr_registration __user *arg) { const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; struct pr_registration reg; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!ops || !ops->pr_register) return -EOPNOTSUPP; if (copy_from_user(&reg, arg, sizeof(reg))) return -EFAULT; if (reg.flags & ~PR_FL_IGNORE_KEY) return -EOPNOTSUPP; return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig113100.00%1100.00%
Total113100.00%1100.00%


static int blkdev_pr_reserve(struct block_device *bdev, struct pr_reservation __user *arg) { const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; struct pr_reservation rsv; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!ops || !ops->pr_reserve) return -EOPNOTSUPP; if (copy_from_user(&rsv, arg, sizeof(rsv))) return -EFAULT; if (rsv.flags & ~PR_FL_IGNORE_KEY) return -EOPNOTSUPP; return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig113100.00%1100.00%
Total113100.00%1100.00%


static int blkdev_pr_release(struct block_device *bdev, struct pr_reservation __user *arg) { const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; struct pr_reservation rsv; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!ops || !ops->pr_release) return -EOPNOTSUPP; if (copy_from_user(&rsv, arg, sizeof(rsv))) return -EFAULT; if (rsv.flags) return -EOPNOTSUPP; return ops->pr_release(bdev, rsv.key, rsv.type); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig106100.00%1100.00%
Total106100.00%1100.00%


static int blkdev_pr_preempt(struct block_device *bdev, struct pr_preempt __user *arg, bool abort) { const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; struct pr_preempt p; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!ops || !ops->pr_preempt) return -EOPNOTSUPP; if (copy_from_user(&p, arg, sizeof(p))) return -EFAULT; if (p.flags) return -EOPNOTSUPP; return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig115100.00%1100.00%
Total115100.00%1100.00%


static int blkdev_pr_clear(struct block_device *bdev, struct pr_clear __user *arg) { const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; struct pr_clear c; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!ops || !ops->pr_clear) return -EOPNOTSUPP; if (copy_from_user(&c, arg, sizeof(c))) return -EFAULT; if (c.flags) return -EOPNOTSUPP; return ops->pr_clear(bdev, c.key); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig102100.00%1100.00%
Total102100.00%1100.00%

/* * Is it an unrecognized ioctl? The correct returns are either * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl * code before returning. * * Confused drivers sometimes return EINVAL, which is wrong. It * means "I understood the ioctl command, but the parameters to * it were wrong". * * We should aim to just fix the broken drivers, the EINVAL case * should go away. */
static inline int is_unrecognized_ioctl(int ret) { return ret == -EINVAL || ret == -ENOTTY || ret == -ENOIOCTLCMD; }

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PersonTokensPropCommitsCommitProp
Linus Torvalds26100.00%1100.00%
Total26100.00%1100.00%


static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long arg) { int ret; if (!capable(CAP_SYS_ADMIN)) return -EACCES; ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); if (!is_unrecognized_ioctl(ret)) return ret; fsync_bdev(bdev); invalidate_bdev(bdev); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro4358.90%450.00%
Linus Torvalds (pre-git)2230.14%112.50%
Linus Torvalds45.48%112.50%
Christoph Hellwig34.11%112.50%
Akinobu Mita11.37%112.50%
Total73100.00%8100.00%


static int blkdev_roset(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long arg) { int ret, n; ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); if (!is_unrecognized_ioctl(ret)) return ret; if (!capable(CAP_SYS_ADMIN)) return -EACCES; if (get_user(n, (int __user *)arg)) return -EFAULT; set_device_ro(bdev, n); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Al Viro3640.00%228.57%
Christoph Hellwig2628.89%114.29%
Andrew Morton2123.33%228.57%
Linus Torvalds44.44%114.29%
Linus Torvalds (pre-git)33.33%114.29%
Total90100.00%7100.00%


static int blkdev_getgeo(struct block_device *bdev, struct hd_geometry __user *argp) { struct gendisk *disk = bdev->bd_disk; struct hd_geometry geo; int ret; if (!argp) return -EINVAL; if (!disk->fops->getgeo) return -ENOTTY; /* * We need to set the startsect first, the driver may * want to override it. */ memset(&geo, 0, sizeof(geo)); geo.start = get_start_sect(bdev); ret = disk->fops->getgeo(bdev, &geo); if (ret) return ret; if (copy_to_user(argp, &geo, sizeof(geo))) return -EFAULT; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig9477.69%114.29%
Al Viro1512.40%228.57%
Andrew Morton108.26%228.57%
Linus Torvalds (pre-git)10.83%114.29%
Adrian Hunter10.83%114.29%
Total121100.00%7100.00%

/* set the logical block size */
static int blkdev_bszset(struct block_device *bdev, fmode_t mode, int __user *argp) { int ret, n; if (!capable(CAP_SYS_ADMIN)) return -EACCES; if (!argp) return -EINVAL; if (get_user(n, argp)) return -EFAULT; if (!(mode & FMODE_EXCL)) { bdgrab(bdev); if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0) return -EBUSY; } ret = set_blocksize(bdev, n); if (!(mode & FMODE_EXCL)) blkdev_put(bdev, mode | FMODE_EXCL); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig9576.61%150.00%
Martin K. Petersen2923.39%150.00%
Total124100.00%2100.00%

/* * always keep this in sync with compat_blkdev_ioctl() */
int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long arg) { void __user *argp = (void __user *)arg; loff_t size; unsigned int max_sectors; switch (cmd) { case BLKFLSBUF: return blkdev_flushbuf(bdev, mode, cmd, arg); case BLKROSET: return blkdev_roset(bdev, mode, cmd, arg); case BLKDISCARD: return blk_ioctl_discard(bdev, mode, arg, 0); case BLKSECDISCARD: return blk_ioctl_discard(bdev, mode, arg, BLKDEV_DISCARD_SECURE); case BLKZEROOUT: return blk_ioctl_zeroout(bdev, mode, arg); case BLKREPORTZONE: return blkdev_report_zones_ioctl(bdev, mode, cmd, arg); case BLKRESETZONE: return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg); case HDIO_GETGEO: return blkdev_getgeo(bdev, argp); case BLKRAGET: case BLKFRAGET: if (!arg) return -EINVAL; return put_long(arg, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512); case BLKROGET: return put_int(arg, bdev_read_only(bdev) != 0); case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ return put_int(arg, block_size(bdev)); case BLKSSZGET: /* get block device logical block size */ return put_int(arg, bdev_logical_block_size(bdev)); case BLKPBSZGET: /* get block device physical block size */ return put_uint(arg, bdev_physical_block_size(bdev)); case BLKIOMIN: return put_uint(arg, bdev_io_min(bdev)); case BLKIOOPT: return put_uint(arg, bdev_io_opt(bdev)); case BLKALIGNOFF: return put_int(arg, bdev_alignment_offset(bdev)); case BLKDISCARDZEROES: return put_uint(arg, bdev_discard_zeroes_data(bdev)); case BLKSECTGET: max_sectors = min_t(unsigned int, USHRT_MAX, queue_max_sectors(bdev_get_queue(bdev))); return put_ushort(arg, max_sectors); case BLKROTATIONAL: return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev))); case BLKRASET: case BLKFRASET: if(!capable(CAP_SYS_ADMIN)) return -EACCES; bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE; return 0; case BLKBSZSET: return blkdev_bszset(bdev, mode, argp); case BLKPG: return blkpg_ioctl(bdev, argp); case BLKRRPART: return blkdev_reread_part(bdev); case BLKGETSIZE: size = i_size_read(bdev->bd_inode); if ((size >> 9) > ~0UL) return -EFBIG; return put_ulong(arg, size >> 9); case BLKGETSIZE64: return put_u64(arg, i_size_read(bdev->bd_inode)); case BLKTRACESTART: case BLKTRACESTOP: case BLKTRACESETUP: case BLKTRACETEARDOWN: return blk_trace_ioctl(bdev, cmd, argp); case IOC_PR_REGISTER: return blkdev_pr_register(bdev, argp); case IOC_PR_RESERVE: return blkdev_pr_reserve(bdev, argp); case IOC_PR_RELEASE: return blkdev_pr_release(bdev, argp); case IOC_PR_PREEMPT: return blkdev_pr_preempt(bdev, argp, false); case IOC_PR_PREEMPT_ABORT: return blkdev_pr_preempt(bdev, argp, true); case IOC_PR_CLEAR: return blkdev_pr_clear