Merge tag 'for-5.8/drivers-2020-06-01' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "On top of the core changes, here are the block driver changes for this
  merge window:

   - NVMe changes:
        - NVMe over Fibre Channel protocol updates, which also reach
          over to drivers/scsi/lpfc (James Smart)
        - namespace revalidation support on the target (Anthony
          Iliopoulos)
        - gcc zero length array fix (Arnd Bergmann)
        - nvmet cleanups (Chaitanya Kulkarni)
        - misc cleanups and fixes (me, Keith Busch, Sagi Grimberg)
        - use a SRQ per completion vector (Max Gurtovoy)
        - fix handling of runtime changes to the queue count (Weiping
          Zhang)
        - t10 protection information support for nvme-rdma and
          nvmet-rdma (Israel Rukshin and Max Gurtovoy)
        - target side AEN improvements (Chaitanya Kulkarni)
        - various fixes and minor improvements all over, icluding the
          nvme part of the lpfc driver"

   - Floppy code cleanup series (Willy, Denis)

   - Floppy contention fix (Jiri)

   - Loop CONFIGURE support (Martijn)

   - bcache fixes/improvements (Coly, Joe, Colin)

   - q->queuedata cleanups (Christoph)

   - Get rid of ioctl_by_bdev (Christoph, Stefan)

   - md/raid5 allocation fixes (Coly)

   - zero length array fixes (Gustavo)

   - swim3 task state fix (Xu)"

* tag 'for-5.8/drivers-2020-06-01' of git://git.kernel.dk/linux-block: (166 commits)
  bcache: configure the asynchronous registertion to be experimental
  bcache: asynchronous devices registration
  bcache: fix refcount underflow in bcache_device_free()
  bcache: Convert pr_<level> uses to a more typical style
  bcache: remove redundant variables i and n
  lpfc: Fix return value in __lpfc_nvme_ls_abort
  lpfc: fix axchg pointer reference after free and double frees
  lpfc: Fix pointer checks and comments in LS receive refactoring
  nvme: set dma alignment to qword
  nvmet: cleanups the loop in nvmet_async_events_process
  nvmet: fix memory leak when removing namespaces and controllers concurrently
  nvmet-rdma: add metadata/T10-PI support
  nvmet: add metadata support for block devices
  nvmet: add metadata/T10-PI support
  nvme: add Metadata Capabilities enumerations
  nvmet: rename nvmet_check_data_len to nvmet_check_transfer_len
  nvmet: rename nvmet_rw_len to nvmet_rw_data_len
  nvmet: add metadata characteristics for a namespace
  nvme-rdma: add metadata/T10-PI support
  nvme-rdma: introduce nvme_rdma_sgl structure
  ...

3 files changed, 468 insertions, 387 deletions

diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index c3daa64cb52c..3e9db22db2a8 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -337,8 +337,7 @@ static bool initialized;
 /*
  * globals used by 'result()'
  */
-#define MAX_REPLIES 16
-static unsigned char reply_buffer[MAX_REPLIES];
+static unsigned char reply_buffer[FD_RAW_REPLY_SIZE];
 static int inr;		/* size of reply buffer, when called from interrupt */
 #define ST0		0
 #define ST1		1
@@ -595,12 +594,12 @@ static unsigned char in_sector_offset;	/* offset within physical sector,
 
 static inline unsigned char fdc_inb(int fdc, int reg)
 {
-	return fd_inb(fdc_state[fdc].address + reg);
+	return fd_inb(fdc_state[fdc].address, reg);
 }
 
 static inline void fdc_outb(unsigned char value, int fdc, int reg)
 {
-	fd_outb(value, fdc_state[fdc].address + reg);
+	fd_outb(value, fdc_state[fdc].address, reg);
 }
 
 static inline bool drive_no_geom(int drive)
@@ -668,16 +667,12 @@ static struct output_log {
 
 static int output_log_pos;
 
-#define current_reqD -1
 #define MAXTIMEOUT -2
 
 static void __reschedule_timeout(int drive, const char *message)
 {
 	unsigned long delay;
 
-	if (drive == current_reqD)
-		drive = current_drive;
-
 	if (drive < 0 || drive >= N_DRIVE) {
 		delay = 20UL * HZ;
 		drive = 0;
@@ -827,59 +822,70 @@ static int set_dor(int fdc, char mask, char data)
 	return olddor;
 }
 
-static void twaddle(void)
+static void twaddle(int fdc, int drive)
 {
-	if (drive_params[current_drive].select_delay)
+	if (drive_params[drive].select_delay)
 		return;
-	fdc_outb(fdc_state[current_fdc].dor & ~(0x10 << UNIT(current_drive)),
-		 current_fdc, FD_DOR);
-	fdc_outb(fdc_state[current_fdc].dor, current_fdc, FD_DOR);
-	drive_state[current_drive].select_date = jiffies;
+	fdc_outb(fdc_state[fdc].dor & ~(0x10 << UNIT(drive)),
+		 fdc, FD_DOR);
+	fdc_outb(fdc_state[fdc].dor, fdc, FD_DOR);
+	drive_state[drive].select_date = jiffies;
 }
 
 /*
- * Reset all driver information about the current fdc.
+ * Reset all driver information about the specified fdc.
  * This is needed after a reset, and after a raw command.
  */
-static void reset_fdc_info(int mode)
+static void reset_fdc_info(int fdc, int mode)
 {
 	int drive;
 
-	fdc_state[current_fdc].spec1 = fdc_state[current_fdc].spec2 = -1;
-	fdc_state[current_fdc].need_configure = 1;
-	fdc_state[current_fdc].perp_mode = 1;
-	fdc_state[current_fdc].rawcmd = 0;
+	fdc_state[fdc].spec1 = fdc_state[fdc].spec2 = -1;
+	fdc_state[fdc].need_configure = 1;
+	fdc_state[fdc].perp_mode = 1;
+	fdc_state[fdc].rawcmd = 0;
 	for (drive = 0; drive < N_DRIVE; drive++)
-		if (FDC(drive) == current_fdc &&
+		if (FDC(drive) == fdc &&
 		    (mode || drive_state[drive].track != NEED_1_RECAL))
 			drive_state[drive].track = NEED_2_RECAL;
 }
 
-/* selects the fdc and drive, and enables the fdc's input/dma. */
+/*
+ * selects the fdc and drive, and enables the fdc's input/dma.
+ * Both current_drive and current_fdc are changed to match the new drive.
+ */
 static void set_fdc(int drive)
 {
-	unsigned int new_fdc = current_fdc;
+	unsigned int fdc;
 
-	if (drive >= 0 && drive < N_DRIVE) {
-		new_fdc = FDC(drive);
-		current_drive = drive;
+	if (drive < 0 || drive >= N_DRIVE) {
+		pr_info("bad drive value %d\n", drive);
+		return;
 	}
-	if (new_fdc >= N_FDC) {
+
+	fdc = FDC(drive);
+	if (fdc >= N_FDC) {
 		pr_info("bad fdc value\n");
 		return;
 	}
-	current_fdc = new_fdc;
-	set_dor(current_fdc, ~0, 8);
+
+	set_dor(fdc, ~0, 8);
 #if N_FDC > 1
-	set_dor(1 - current_fdc, ~8, 0);
+	set_dor(1 - fdc, ~8, 0);
 #endif
-	if (fdc_state[current_fdc].rawcmd == 2)
-		reset_fdc_info(1);
-	if (fdc_inb(current_fdc, FD_STATUS) != STATUS_READY)
-		fdc_state[current_fdc].reset = 1;
+	if (fdc_state[fdc].rawcmd == 2)
+		reset_fdc_info(fdc, 1);
+	if (fdc_inb(fdc, FD_STATUS) != STATUS_READY)
+		fdc_state[fdc].reset = 1;
+
+	current_drive = drive;
+	current_fdc = fdc;
 }
 
-/* locks the driver */
+/*
+ * locks the driver.
+ * Both current_drive and current_fdc are changed to match the new drive.
+ */
 static int lock_fdc(int drive)
 {
 	if (WARN(atomic_read(&usage_count) == 0,
@@ -1062,12 +1068,9 @@ static void setup_DMA(void)
 	unsigned long f;
 
 	if (raw_cmd->length == 0) {
-		int i;
-
-		pr_info("zero dma transfer size:");
-		for (i = 0; i < raw_cmd->cmd_count; i++)
-			pr_cont("%x,", raw_cmd->cmd[i]);
-		pr_cont("\n");
+		print_hex_dump(KERN_INFO, "zero dma transfer size: ",
+			       DUMP_PREFIX_NONE, 16, 1,
+			       raw_cmd->fullcmd, raw_cmd->cmd_count, false);
 		cont->done(0);
 		fdc_state[current_fdc].reset = 1;
 		return;
@@ -1104,62 +1107,62 @@ static void setup_DMA(void)
 #endif
 }
 
-static void show_floppy(void);
+static void show_floppy(int fdc);
 
 /* waits until the fdc becomes ready */
-static int wait_til_ready(void)
+static int wait_til_ready(int fdc)
 {
 	int status;
 	int counter;
 
-	if (fdc_state[current_fdc].reset)
+	if (fdc_state[fdc].reset)
 		return -1;
 	for (counter = 0; counter < 10000; counter++) {
-		status = fdc_inb(current_fdc, FD_STATUS);
+		status = fdc_inb(fdc, FD_STATUS);
 		if (status & STATUS_READY)
 			return status;
 	}
 	if (initialized) {
-		DPRINT("Getstatus times out (%x) on fdc %d\n", status, current_fdc);
-		show_floppy();
+		DPRINT("Getstatus times out (%x) on fdc %d\n", status, fdc);
+		show_floppy(fdc);
 	}
-	fdc_state[current_fdc].reset = 1;
+	fdc_state[fdc].reset = 1;
 	return -1;
 }
 
 /* sends a command byte to the fdc */
-static int output_byte(char byte)
+static int output_byte(int fdc, char byte)
 {
-	int status = wait_til_ready();
+	int status = wait_til_ready(fdc);
 
 	if (status < 0)
 		return -1;
 
 	if (is_ready_state(status)) {
-		fdc_outb(byte, current_fdc, FD_DATA);
+		fdc_outb(byte, fdc, FD_DATA);
 		output_log[output_log_pos].data = byte;
 		output_log[output_log_pos].status = status;
 		output_log[output_log_pos].jiffies = jiffies;
 		output_log_pos = (output_log_pos + 1) % OLOGSIZE;
 		return 0;
 	}
-	fdc_state[current_fdc].reset = 1;
+	fdc_state[fdc].reset = 1;
 	if (initialized) {
 		DPRINT("Unable to send byte %x to FDC. Fdc=%x Status=%x\n",
-		       byte, current_fdc, status);
-		show_floppy();
+		       byte, fdc, status);
+		show_floppy(fdc);
 	}
 	return -1;
 }
 
 /* gets the response from the fdc */
-static int result(void)
+static int result(int fdc)
 {
 	int i;
 	int status = 0;
 
-	for (i = 0; i < MAX_REPLIES; i++) {
-		status = wait_til_ready();
+	for (i = 0; i < FD_RAW_REPLY_SIZE; i++) {
+		status = wait_til_ready(fdc);
 		if (status < 0)
 			break;
 		status &= STATUS_DIR | STATUS_READY | STATUS_BUSY | STATUS_DMA;
@@ -1169,24 +1172,24 @@ static int result(void)
 			return i;
 		}
 		if (status == (STATUS_DIR | STATUS_READY | STATUS_BUSY))
-			reply_buffer[i] = fdc_inb(current_fdc, FD_DATA);
+			reply_buffer[i] = fdc_inb(fdc, FD_DATA);
 		else
 			break;
 	}
 	if (initialized) {
 		DPRINT("get result error. Fdc=%d Last status=%x Read bytes=%d\n",
-		       current_fdc, status, i);
-		show_floppy();
+		       fdc, status, i);
+		show_floppy(fdc);
 	}
-	fdc_state[current_fdc].reset = 1;
+	fdc_state[fdc].reset = 1;
 	return -1;
 }
 
 #define MORE_OUTPUT -2
 /* does the fdc need more output? */
-static int need_more_output(void)
+static int need_more_output(int fdc)
 {
-	int status = wait_til_ready();
+	int status = wait_til_ready(fdc);
 
 	if (status < 0)
 		return -1;
@@ -1194,13 +1197,13 @@ static int need_more_output(void)
 	if (is_ready_state(status))
 		return MORE_OUTPUT;
 
-	return result();
+	return result(fdc);
 }
 
 /* Set perpendicular mode as required, based on data rate, if supported.
  * 82077 Now tested. 1Mbps data rate only possible with 82077-1.
  */
-static void perpendicular_mode(void)
+static void perpendicular_mode(int fdc)
 {
 	unsigned char perp_mode;
 
@@ -1215,7 +1218,7 @@ static void perpendicular_mode(void)
 		default:
 			DPRINT("Invalid data rate for perpendicular mode!\n");
 			cont->done(0);
-			fdc_state[current_fdc].reset = 1;
+			fdc_state[fdc].reset = 1;
 					/*
 					 * convenient way to return to
 					 * redo without too much hassle
@@ -1226,12 +1229,12 @@ static void perpendicular_mode(void)
 	} else
 		perp_mode = 0;
 
-	if (fdc_state[current_fdc].perp_mode == perp_mode)
+	if (fdc_state[fdc].perp_mode == perp_mode)
 		return;
-	if (fdc_state[current_fdc].version >= FDC_82077_ORIG) {
-		output_byte(FD_PERPENDICULAR);
-		output_byte(perp_mode);
-		fdc_state[current_fdc].perp_mode = perp_mode;
+	if (fdc_state[fdc].version >= FDC_82077_ORIG) {
+		output_byte(fdc, FD_PERPENDICULAR);
+		output_byte(fdc, perp_mode);
+		fdc_state[fdc].perp_mode = perp_mode;
 	} else if (perp_mode) {
 		DPRINT("perpendicular mode not supported by this FDC.\n");
 	}
@@ -1240,16 +1243,15 @@ static void perpendicular_mode(void)
 static int fifo_depth = 0xa;
 static int no_fifo;
 
-static int fdc_configure(void)
+static int fdc_configure(int fdc)
 {
 	/* Turn on FIFO */
-	output_byte(FD_CONFIGURE);
-	if (need_more_output() != MORE_OUTPUT)
+	output_byte(fdc, FD_CONFIGURE);
+	if (need_more_output(fdc) != MORE_OUTPUT)
 		return 0;
-	output_byte(0);
-	output_byte(0x10 | (no_fifo & 0x20) | (fifo_depth & 0xf));
-	output_byte(0);		/* pre-compensation from track
-				   0 upwards */
+	output_byte(fdc, 0);
+	output_byte(fdc, 0x10 | (no_fifo & 0x20) | (fifo_depth & 0xf));
+	output_byte(fdc, 0);    /* pre-compensation from track 0 upwards */
 	return 1;
 }
 
@@ -1274,7 +1276,7 @@ static int fdc_configure(void)
  *
  * These values are rounded up to the next highest available delay time.
  */
-static void fdc_specify(void)
+static void fdc_specify(int fdc, int drive)
 {
 	unsigned char spec1;
 	unsigned char spec2;
@@ -1286,10 +1288,10 @@ static void fdc_specify(void)
 	int hlt_max_code = 0x7f;
 	int hut_max_code = 0xf;
 
-	if (fdc_state[current_fdc].need_configure &&
-	    fdc_state[current_fdc].version >= FDC_82072A) {
-		fdc_configure();
-		fdc_state[current_fdc].need_configure = 0;
+	if (fdc_state[fdc].need_configure &&
+	    fdc_state[fdc].version >= FDC_82072A) {
+		fdc_configure(fdc);
+		fdc_state[fdc].need_configure = 0;
 	}
 
 	switch (raw_cmd->rate & 0x03) {
@@ -1298,13 +1300,13 @@ static void fdc_specify(void)
 		break;
 	case 1:
 		dtr = 300;
-		if (fdc_state[current_fdc].version >= FDC_82078) {
+		if (fdc_state[fdc].version >= FDC_82078) {
 			/* chose the default rate table, not the one
 			 * where 1 = 2 Mbps */
-			output_byte(FD_DRIVESPEC);
-			if (need_more_output() == MORE_OUTPUT) {
-				output_byte(UNIT(current_drive));
-				output_byte(0xc0);
+			output_byte(fdc, FD_DRIVESPEC);
+			if (need_more_output(fdc) == MORE_OUTPUT) {
+				output_byte(fdc, UNIT(drive));
+				output_byte(fdc, 0xc0);
 			}
 		}
 		break;
@@ -1313,14 +1315,14 @@ static void fdc_specify(void)
 		break;
 	}
 
-	if (fdc_state[current_fdc].version >= FDC_82072) {
+	if (fdc_state[fdc].version >= FDC_82072) {
 		scale_dtr = dtr;
 		hlt_max_code = 0x00;	/* 0==256msec*dtr0/dtr (not linear!) */
 		hut_max_code = 0x0;	/* 0==256msec*dtr0/dtr (not linear!) */
 	}
 
 	/* Convert step rate from microseconds to milliseconds and 4 bits */
-	srt = 16 - DIV_ROUND_UP(drive_params[current_drive].srt * scale_dtr / 1000,
+	srt = 16 - DIV_ROUND_UP(drive_params[drive].srt * scale_dtr / 1000,
 				NOMINAL_DTR);
 	if (slow_floppy)
 		srt = srt / 4;
@@ -1328,14 +1330,14 @@ static void fdc_specify(void)
 	SUPBOUND(srt, 0xf);
 	INFBOUND(srt, 0);
 
-	hlt = DIV_ROUND_UP(drive_params[current_drive].hlt * scale_dtr / 2,
+	hlt = DIV_ROUND_UP(drive_params[drive].hlt * scale_dtr / 2,
 			   NOMINAL_DTR);
 	if (hlt < 0x01)
 		hlt = 0x01;
 	else if (hlt > 0x7f)
 		hlt = hlt_max_code;
 
-	hut = DIV_ROUND_UP(drive_params[current_drive].hut * scale_dtr / 16,
+	hut = DIV_ROUND_UP(drive_params[drive].hut * scale_dtr / 16,
 			   NOMINAL_DTR);
 	if (hut < 0x1)
 		hut = 0x1;
@@ -1346,12 +1348,12 @@ static void fdc_specify(void)
 	spec2 = (hlt << 1) | (use_virtual_dma & 1);
 
 	/* If these parameters did not change, just return with success */
-	if (fdc_state[current_fdc].spec1 != spec1 ||
-	    fdc_state[current_fdc].spec2 != spec2) {
+	if (fdc_state[fdc].spec1 != spec1 ||
+	    fdc_state[fdc].spec2 != spec2) {
 		/* Go ahead and set spec1 and spec2 */
-		output_byte(FD_SPECIFY);
-		output_byte(fdc_state[current_fdc].spec1 = spec1);
-		output_byte(fdc_state[current_fdc].spec2 = spec2);
+		output_byte(fdc, FD_SPECIFY);
+		output_byte(fdc, fdc_state[fdc].spec1 = spec1);
+		output_byte(fdc, fdc_state[fdc].spec2 = spec2);
 	}
 }				/* fdc_specify */
 
@@ -1513,7 +1515,7 @@ static void setup_rw_floppy(void)
 
 	r = 0;
 	for (i = 0; i < raw_cmd->cmd_count; i++)
-		r |= output_byte(raw_cmd->cmd[i]);
+		r |= output_byte(current_fdc, raw_cmd->fullcmd[i]);
 
 	debugt(__func__, "rw_command");
 
@@ -1524,7 +1526,7 @@ static void setup_rw_floppy(void)
 	}
 
 	if (!(flags & FD_RAW_INTR)) {
-		inr = result();
+		inr = result(current_fdc);
 		cont->interrupt();
 	} else if (flags & FD_RAW_NEED_DISK)
 		fd_watchdog();
@@ -1562,29 +1564,29 @@ static void seek_interrupt(void)
 	floppy_ready();
 }
 
-static void check_wp(void)
+static void check_wp(int fdc, int drive)
 {
-	if (test_bit(FD_VERIFY_BIT, &drive_state[current_drive].flags)) {
+	if (test_bit(FD_VERIFY_BIT, &drive_state[drive].flags)) {
 					/* check write protection */
-		output_byte(FD_GETSTATUS);
-		output_byte(UNIT(current_drive));
-		if (result() != 1) {
-			fdc_state[current_fdc].reset = 1;
+		output_byte(fdc, FD_GETSTATUS);
+		output_byte(fdc, UNIT(drive));
+		if (result(fdc) != 1) {
+			fdc_state[fdc].reset = 1;
 			return;
 		}
-		clear_bit(FD_VERIFY_BIT, &drive_state[current_drive].flags);
+		clear_bit(FD_VERIFY_BIT, &drive_state[drive].flags);
 		clear_bit(FD_NEED_TWADDLE_BIT,
-			  &drive_state[current_drive].flags);
-		debug_dcl(drive_params[current_drive].flags,
+			  &drive_state[drive].flags);
+		debug_dcl(drive_params[drive].flags,
 			  "checking whether disk is write protected\n");
-		debug_dcl(drive_params[current_drive].flags, "wp=%x\n",
+		debug_dcl(drive_params[drive].flags, "wp=%x\n",
 			  reply_buffer[ST3] & 0x40);
 		if (!(reply_buffer[ST3] & 0x40))
 			set_bit(FD_DISK_WRITABLE_BIT,
-				&drive_state[current_drive].flags);
+				&drive_state[drive].flags);
 		else
 			clear_bit(FD_DISK_WRITABLE_BIT,
-				  &drive_state[current_drive].flags);
+				  &drive_state[drive].flags);
 	}
 }
 
@@ -1628,7 +1630,7 @@ static void seek_floppy(void)
 			track = 1;
 		}
 	} else {
-		check_wp();
+		check_wp(current_fdc, current_drive);
 		if (raw_cmd->track != drive_state[current_drive].track &&
 		    (raw_cmd->flags & FD_RAW_NEED_SEEK))
 			track = raw_cmd->track;
@@ -1639,9 +1641,9 @@ static void seek_floppy(void)
 	}
 
 	do_floppy = seek_interrupt;
-	output_byte(FD_SEEK);
-	output_byte(UNIT(current_drive));
-	if (output_byte(track) < 0) {
+	output_byte(current_fdc, FD_SEEK);
+	output_byte(current_fdc, UNIT(current_drive));
+	if (output_byte(current_fdc, track) < 0) {
 		reset_fdc();
 		return;
 	}
@@ -1742,14 +1744,14 @@ irqreturn_t floppy_interrupt(int irq, void *dev_id)
 
 	do_print = !handler && print_unex && initialized;
 
-	inr = result();
+	inr = result(current_fdc);
 	if (do_print)
 		print_result("unexpected interrupt", inr);
 	if (inr == 0) {
 		int max_sensei = 4;
 		do {
-			output_byte(FD_SENSEI);
-			inr = result();
+			output_byte(current_fdc, FD_SENSEI);
+			inr = result(current_fdc);
 			if (do_print)
 				print_result("sensei", inr);
 			max_sensei--;
@@ -1771,8 +1773,8 @@ static void recalibrate_floppy(void)
 {
 	debugt(__func__, "");
 	do_floppy = recal_interrupt;
-	output_byte(FD_RECALIBRATE);
-	if (output_byte(UNIT(current_drive)) < 0)
+	output_byte(current_fdc, FD_RECALIBRATE);
+	if (output_byte(current_fdc, UNIT(current_drive)) < 0)
 		reset_fdc();
 }
 
@@ -1782,7 +1784,7 @@ static void recalibrate_floppy(void)
 static void reset_interrupt(void)
 {
 	debugt(__func__, "");
-	result();		/* get the status ready for set_fdc */
+	result(current_fdc);		/* get the status ready for set_fdc */
 	if (fdc_state[current_fdc].reset) {
 		pr_info("reset set in interrupt, calling %ps\n", cont->error);
 		cont->error();	/* a reset just after a reset. BAD! */
@@ -1792,7 +1794,9 @@ static void reset_interrupt(void)
 
 /*
  * reset is done by pulling bit 2 of DOR low for a while (old FDCs),
- * or by setting the self clearing bit 7 of STATUS (newer FDCs)
+ * or by setting the self clearing bit 7 of STATUS (newer FDCs).
+ * This WILL trigger an interrupt, causing the handlers in the current
+ * cont's ->redo() to be called via reset_interrupt().
  */
 static void reset_fdc(void)
 {
@@ -1800,7 +1804,7 @@ static void reset_fdc(void)
 
 	do_floppy = reset_interrupt;
 	fdc_state[current_fdc].reset = 0;
-	reset_fdc_info(0);
+	reset_fdc_info(current_fdc, 0);
 
 	/* Pseudo-DMA may intercept 'reset finished' interrupt.  */
 	/* Irrelevant for systems with true DMA (i386).          */
@@ -1819,7 +1823,7 @@ static void reset_fdc(void)
 	}
 }
 
-static void show_floppy(void)
+static void show_floppy(int fdc)
 {
 	int i;
 
@@ -1842,7 +1846,7 @@ static void show_floppy(void)
 	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE, 16, 1,
 		       reply_buffer, resultsize, true);
 
-	pr_info("status=%x\n", fdc_inb(current_fdc, FD_STATUS));
+	pr_info("status=%x\n", fdc_inb(fdc, FD_STATUS));
 	pr_info("fdc_busy=%lu\n", fdc_busy);
 	if (do_floppy)
 		pr_info("do_floppy=%ps\n", do_floppy);
@@ -1868,7 +1872,7 @@ static void floppy_shutdown(struct work_struct *arg)
 	unsigned long flags;
 
 	if (initialized)
-		show_floppy();
+		show_floppy(current_fdc);
 	cancel_activity();
 
 	flags = claim_dma_lock();
@@ -1934,7 +1938,7 @@ static void floppy_ready(void)
 		  "calling disk change from floppy_ready\n");
 	if (!(raw_cmd->flags & FD_RAW_NO_MOTOR) &&
 	    disk_change(current_drive) && !drive_params[current_drive].select_delay)
-		twaddle();	/* this clears the dcl on certain
+		twaddle(current_fdc, current_drive);	/* this clears the dcl on certain
 				 * drive/controller combinations */
 
 #ifdef fd_chose_dma_mode
@@ -1946,20 +1950,20 @@ static void floppy_ready(void)
 #endif
 
 	if (raw_cmd->flags & (FD_RAW_NEED_SEEK | FD_RAW_NEED_DISK)) {
-		perpendicular_mode();
-		fdc_specify();	/* must be done here because of hut, hlt ... */
+		perpendicular_mode(current_fdc);
+		fdc_specify(current_fdc, current_drive); /* must be done here because of hut, hlt ... */
 		seek_floppy();
 	} else {
 		if ((raw_cmd->flags & FD_RAW_READ) ||
 		    (raw_cmd->flags & FD_RAW_WRITE))
-			fdc_specify();
+			fdc_specify(current_fdc, current_drive);
 		setup_rw_floppy();
 	}
 }
 
 static void floppy_start(void)
 {
-	reschedule_timeout(current_reqD, "floppy start");
+	reschedule_timeout(current_drive, "floppy start");
 
 	scandrives();
 	debug_dcl(drive_params[current_drive].flags,
@@ -2004,6 +2008,9 @@ static const struct cont_t intr_cont = {
 	.done		= (done_f)empty
 };
 
+/* schedules handler, waiting for completion. May be interrupted, will then
+ * return -EINTR, in which case the driver will automatically be unlocked.
+ */
 static int wait_til_done(void (*handler)(void), bool interruptible)
 {
 	int ret;
@@ -2059,18 +2066,19 @@ static void success_and_wakeup(void)
  * ==========================
  */
 
-static int next_valid_format(void)
+static int next_valid_format(int drive)
 {
 	int probed_format;
 
-	probed_format = drive_state[current_drive].probed_format;
+	probed_format = drive_state[drive].probed_format;
 	while (1) {
-		if (probed_format >= 8 || !drive_params[current_drive].autodetect[probed_format]) {
-			drive_state[current_drive].probed_format = 0;
+		if (probed_format >= FD_AUTODETECT_SIZE ||
+		    !drive_params[drive].autodetect[probed_format]) {
+			drive_state[drive].probed_format = 0;
 			return 1;
 		}
-		if (floppy_type[drive_params[current_drive].autodetect[probed_format]].sect) {
-			drive_state[current_drive].probed_format = probed_format;
+		if (floppy_type[drive_params[drive].autodetect[probed_format]].sect) {
+			drive_state[drive].probed_format = probed_format;
 			return 0;
 		}
 		probed_format++;
@@ -2083,7 +2091,7 @@ static void bad_flp_intr(void)
 
 	if (probing) {
 		drive_state[current_drive].probed_format++;
-		if (!next_valid_format())
+		if (!next_valid_format(current_drive))
 			return;
 	}
 	err_count = ++(*errors);
@@ -2843,6 +2851,9 @@ static int set_next_request(void)
 	return current_req != NULL;
 }
 
+/* Starts or continues processing request. Will automatically unlock the
+ * driver at end of request.
+ */
 static void redo_fd_request(void)
 {
 	int drive;
@@ -2867,7 +2878,7 @@ do_request:
 	}
 	drive = (long)current_req->rq_disk->private_data;
 	set_fdc(drive);
-	reschedule_timeout(current_reqD, "redo fd request");
+	reschedule_timeout(current_drive, "redo fd request");
 
 	set_floppy(drive);
 	raw_cmd = &default_raw_cmd;
@@ -2885,7 +2896,7 @@ do_request:
 	if (!_floppy) {	/* Autodetection */
 		if (!probing) {
 			drive_state[current_drive].probed_format = 0;
-			if (next_valid_format()) {
+			if (next_valid_format(current_drive)) {
 				DPRINT("no autodetectable formats\n");
 				_floppy = NULL;
 				request_done(0);
@@ -2904,7 +2915,7 @@ do_request:
 	}
 
 	if (test_bit(FD_NEED_TWADDLE_BIT, &drive_state[current_drive].flags))
-		twaddle();
+		twaddle(current_fdc, current_drive);
 	schedule_bh(floppy_start);
 	debugt(__func__, "queue fd request");
 	return;
@@ -2917,6 +2928,7 @@ static const struct cont_t rw_cont = {
 	.done		= request_done
 };
 
+/* schedule the request and automatically unlock the driver on completion */
 static void process_fd_request(void)
 {
 	cont = &rw_cont;
@@ -2938,17 +2950,17 @@ static blk_status_t floppy_queue_rq(struct blk_mq_hw_ctx *hctx,
 		 (unsigned long long) current_req->cmd_flags))
 		return BLK_STS_IOERR;
 
-	spin_lock_irq(&floppy_lock);
-	list_add_tail(&bd->rq->queuelist, &floppy_reqs);
-	spin_unlock_irq(&floppy_lock);
-
 	if (test_and_set_bit(0, &fdc_busy)) {
 		/* fdc busy, this new request will be treated when the
 		   current one is done */
 		is_alive(__func__, "old request running");
-		return BLK_STS_OK;
+		return BLK_STS_RESOURCE;
 	}
 
+	spin_lock_irq(&floppy_lock);
+	list_add_tail(&bd->rq->queuelist, &floppy_reqs);
+	spin_unlock_irq(&floppy_lock);
+
 	command_status = FD_COMMAND_NONE;
 	__reschedule_timeout(MAXTIMEOUT, "fd_request");
 	set_fdc(0);
@@ -2996,6 +3008,10 @@ static const struct cont_t reset_cont = {
 	.done		= generic_done
 };
 
+/*
+ * Resets the FDC connected to drive <drive>.
+ * Both current_drive and current_fdc are changed to match the new drive.
+ */
 static int user_reset_fdc(int drive, int arg, bool interruptible)
 {
 	int ret;
@@ -3006,6 +3022,9 @@ static int user_reset_fdc(int drive, int arg, bool interruptible)
 	if (arg == FD_RESET_ALWAYS)
 		fdc_state[current_fdc].reset = 1;
 	if (fdc_state[current_fdc].reset) {
+		/* note: reset_fdc will take care of unlocking the driver
+		 * on completion.
+		 */
 		cont = &reset_cont;
 		ret = wait_til_done(reset_fdc, interruptible);
 		if (ret == -EINTR)
@@ -3059,7 +3078,7 @@ static void raw_cmd_done(int flag)
 		raw_cmd->flags |= FD_RAW_HARDFAILURE;
 	} else {
 		raw_cmd->reply_count = inr;
-		if (raw_cmd->reply_count > MAX_REPLIES)
+		if (raw_cmd->reply_count > FD_RAW_REPLY_SIZE)
 			raw_cmd->reply_count = 0;
 		for (i = 0; i < raw_cmd->reply_count; i++)
 			raw_cmd->reply[i] = reply_buffer[i];
@@ -3170,18 +3189,10 @@ loop:
 	if (ret)
 		return -EFAULT;
 	param += sizeof(struct floppy_raw_cmd);
-	if (ptr->cmd_count > 33)
-			/* the command may now also take up the space
-			 * initially intended for the reply & the
-			 * reply count. Needed for long 82078 commands
-			 * such as RESTORE, which takes ... 17 command
-			 * bytes. Murphy's law #137: When you reserve
-			 * 16 bytes for a structure, you'll one day
-			 * discover that you really need 17...
-			 */
+	if (ptr->cmd_count > FD_RAW_CMD_FULLSIZE)
 		return -EINVAL;
 
-	for (i = 0; i < 16; i++)
+	for (i = 0; i < FD_RAW_REPLY_SIZE; i++)
 		ptr->reply[i] = 0;
 	ptr->resultcode = 0;
 
@@ -3423,13 +3434,13 @@ static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 	return 0;
 }
 
-static bool valid_floppy_drive_params(const short autodetect[8],
+static bool valid_floppy_drive_params(const short autodetect[FD_AUTODETECT_SIZE],
 		int native_format)
 {
 	size_t floppy_type_size = ARRAY_SIZE(floppy_type);
 	size_t i = 0;
 
-	for (i = 0; i < 8; ++i) {
+	for (i = 0; i < FD_AUTODETECT_SIZE; ++i) {
 		if (autodetect[i] < 0 ||
 		    autodetect[i] >= floppy_type_size)
 			return false;
@@ -3610,7 +3621,7 @@ static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int
 	case FDTWADDLE:
 		if (lock_fdc(drive))
 			return -EINTR;
-		twaddle();
+		twaddle(current_fdc, current_drive);
 		process_fd_request();
 		return 0;
 	default:
@@ -3654,7 +3665,7 @@ struct compat_floppy_drive_params {
 	struct floppy_max_errors max_errors;
 	char		flags;
 	char		read_track;
-	short		autodetect[8];
+	short		autodetect[FD_AUTODETECT_SIZE];
 	compat_int_t	checkfreq;
 	compat_int_t	native_format;
 };
@@ -4298,79 +4309,79 @@ static const struct block_device_operations floppy_fops = {
 
 /* Determine the floppy disk controller type */
 /* This routine was written by David C. Niemi */
-static char __init get_fdc_version(void)
+static char __init get_fdc_version(int fdc)
 {
 	int r;
 
-	output_byte(FD_DUMPREGS);	/* 82072 and better know DUMPREGS */
-	if (fdc_state[current_fdc].reset)
+	output_byte(fdc, FD_DUMPREGS);	/* 82072 and better know DUMPREGS */
+	if (fdc_state[fdc].reset)
 		return FDC_NONE;
-	r = result();
+	r = result(fdc);
 	if (r <= 0x00)
 		return FDC_NONE;	/* No FDC present ??? */
 	if ((r == 1) && (reply_buffer[0] == 0x80)) {
-		pr_info("FDC %d is an 8272A\n", current_fdc);
+		pr_info("FDC %d is an 8272A\n", fdc);
 		return FDC_8272A;	/* 8272a/765 don't know DUMPREGS */
 	}
 	if (r != 10) {
 		pr_info("FDC %d init: DUMPREGS: unexpected return of %d bytes.\n",
-			current_fdc, r);
+			fdc, r);
 		return FDC_UNKNOWN;
 	}
 
-	if (!fdc_configure()) {
-		pr_info("FDC %d is an 82072\n", current_fdc);
+	if (!fdc_configure(fdc)) {
+		pr_info("FDC %d is an 82072\n", fdc);
 		return FDC_82072;	/* 82072 doesn't know CONFIGURE */
 	}
 
-	output_byte(FD_PERPENDICULAR);
-	if (need_more_output() == MORE_OUTPUT) {
-		output_byte(0);
+	output_byte(fdc, FD_PERPENDICULAR);
+	if (need_more_output(fdc) == MORE_OUTPUT) {
+		output_byte(fdc, 0);
 	} else {
-		pr_info("FDC %d is an 82072A\n", current_fdc);
+		pr_info("FDC %d is an 82072A\n", fdc);
 		return FDC_82072A;	/* 82072A as found on Sparcs. */
 	}
 
-	output_byte(FD_UNLOCK);
-	r = result();
+	output_byte(fdc, FD_UNLOCK);
+	r = result(fdc);
 	if ((r == 1) && (reply_buffer[0] == 0x80)) {
-		pr_info("FDC %d is a pre-1991 82077\n", current_fdc);
+		pr_info("FDC %d is a pre-1991 82077\n", fdc);
 		return FDC_82077_ORIG;	/* Pre-1991 82077, doesn't know
 					 * LOCK/UNLOCK */
 	}
 	if ((r != 1) || (reply_buffer[0] != 0x00)) {
 		pr_info("FDC %d init: UNLOCK: unexpected return of %d bytes.\n",
-			current_fdc, r);
+			fdc, r);
 		return FDC_UNKNOWN;
 	}
-	output_byte(FD_PARTID);
-	r = result();
+	output_byte(fdc, FD_PARTID);
+	r = result(fdc);
 	if (r != 1) {
 		pr_info("FDC %d init: PARTID: unexpected return of %d bytes.\n",
-			current_fdc, r);
+			fdc, r);
 		return FDC_UNKNOWN;
 	}
 	if (reply_buffer[0] == 0x80) {
-		pr_info("FDC %d is a post-1991 82077\n", current_fdc);
+		pr_info("FDC %d is a post-1991 82077\n", fdc);
 		return FDC_82077;	/* Revised 82077AA passes all the tests */
 	}
 	switch (reply_buffer[0] >> 5) {
 	case 0x0:
 		/* Either a 82078-1 or a 82078SL running at 5Volt */
-		pr_info("FDC %d is an 82078.\n", current_fdc);
+		pr_info("FDC %d is an 82078.\n", fdc);
 		return FDC_82078;
 	case 0x1:
-		pr_info("FDC %d is a 44pin 82078\n", current_fdc);
+		pr_info("FDC %d is a 44pin 82078\n", fdc);
 		return FDC_82078;
 	case 0x2:
-		pr_info("FDC %d is a S82078B\n", current_fdc);
+		pr_info("FDC %d is a S82078B\n", fdc);
 		return FDC_S82078B;
 	case 0x3:
-		pr_info("FDC %d is a National Semiconductor PC87306\n", current_fdc);
+		pr_info("FDC %d is a National Semiconductor PC87306\n", fdc);
 		return FDC_87306;
 	default:
 		pr_info("FDC %d init: 82078 variant with unknown PARTID=%d.\n",
-			current_fdc, reply_buffer[0] >> 5);
+			fdc, reply_buffer[0] >> 5);
 		return FDC_82078_UNKN;
 	}
 }				/* get_fdc_version */
@@ -4534,11 +4545,13 @@ static void floppy_device_release(struct device *dev)
 static int floppy_resume(struct device *dev)
 {
 	int fdc;
+	int saved_drive;
 
+	saved_drive = current_drive;
 	for (fdc = 0; fdc < N_FDC; fdc++)
 		if (fdc_state[fdc].address != -1)
-			user_reset_fdc(-1, FD_RESET_ALWAYS, false);
-
+			user_reset_fdc(REVDRIVE(fdc, 0), FD_RESET_ALWAYS, false);
+	set_fdc(saved_drive);
 	return 0;
 }
 
@@ -4646,16 +4659,15 @@ static int __init do_floppy_init(void)
 	config_types();
 
 	for (i = 0; i < N_FDC; i++) {
-		current_fdc = i;
-		memset(&fdc_state[current_fdc], 0, sizeof(*fdc_state));
-		fdc_state[current_fdc].dtr = -1;
-		fdc_state[current_fdc].dor = 0x4;
+		memset(&fdc_state[i], 0, sizeof(*fdc_state));
+		fdc_state[i].dtr = -1;
+		fdc_state[i].dor = 0x4;
 #if defined(__sparc__) || defined(__mc68000__)
 	/*sparcs/sun3x don't have a DOR reset which we can fall back on to */
 #ifdef __mc68000__
 		if (MACH_IS_SUN3X)
 #endif
-			fdc_state[current_fdc].version = FDC_82072A;
+			fdc_state[i].version = FDC_82072A;
 #endif
 	}
 
@@ -4697,30 +4709,29 @@ static int __init do_floppy_init(void)
 	msleep(10);
 
 	for (i = 0; i < N_FDC; i++) {
-		current_fdc = i;
-		fdc_state[current_fdc].driver_version = FD_DRIVER_VERSION;
+		fdc_state[i].driver_version = FD_DRIVER_VERSION;
 		for (unit = 0; unit < 4; unit++)
-			fdc_state[current_fdc].track[unit] = 0;
-		if (fdc_state[current_fdc].address == -1)
+			fdc_state[i].track[unit] = 0;
+		if (fdc_state[i].address == -1)
 			continue;
-		fdc_state[current_fdc].rawcmd = 2;
-		if (user_reset_fdc(-1, FD_RESET_ALWAYS, false)) {
+		fdc_state[i].rawcmd = 2;
+		if (user_reset_fdc(REVDRIVE(i, 0), FD_RESET_ALWAYS, false)) {
 			/* free ioports reserved by floppy_grab_irq_and_dma() */
-			floppy_release_regions(current_fdc);
-			fdc_state[current_fdc].address = -1;
-			fdc_state[current_fdc].version = FDC_NONE;
+			floppy_release_regions(i);
+			fdc_state[i].address = -1;
+			fdc_state[i].version = FDC_NONE;
 			continue;
 		}
 		/* Try to determine the floppy controller type */
-		fdc_state[current_fdc].version = get_fdc_version();
-		if (fdc_state[current_fdc].version == FDC_NONE) {
+		fdc_state[i].version = get_fdc_version(i);
+		if (fdc_state[i].version == FDC_NONE) {
 			/* free ioports reserved by floppy_grab_irq_and_dma() */
-			floppy_release_regions(current_fdc);
-			fdc_state[current_fdc].address = -1;
+			floppy_release_regions(i);
+			fdc_state[i].address = -1;
 			continue;
 		}
 		if (can_use_virtual_dma == 2 &&
-		    fdc_state[current_fdc].version < FDC_82072A)
+		    fdc_state[i].version < FDC_82072A)
 			can_use_virtual_dma = 0;
 
 		have_no_fdc = 0;
@@ -4728,7 +4739,7 @@ static int __init do_floppy_init(void)
 		 * properly, so force a reset for the standard FDC clones,
 		 * to avoid interrupt garbage.
 		 */
-		user_reset_fdc(-1, FD_RESET_ALWAYS, false);
+		user_reset_fdc(REVDRIVE(i, 0), FD_RESET_ALWAYS, false);
 	}
 	current_fdc = 0;
 	cancel_delayed_work(&fd_timeout);
@@ -4855,6 +4866,8 @@ static void floppy_release_regions(int fdc)
 
 static int floppy_grab_irq_and_dma(void)
 {
+	int fdc;
+
 	if (atomic_inc_return(&usage_count) > 1)
 		return 0;
 
@@ -4882,24 +4895,24 @@ static int floppy_grab_irq_and_dma(void)
 		}
 	}
 
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++) {
-		if (fdc_state[current_fdc].address != -1) {
-			if (floppy_request_regions(current_fdc))
+	for (fdc = 0; fdc < N_FDC; fdc++) {
+		if (fdc_state[fdc].address != -1) {
+			if (floppy_request_regions(fdc))
 				goto cleanup;
 		}
 	}
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++) {
-		if (fdc_state[current_fdc].address != -1) {
-			reset_fdc_info(1);
-			fdc_outb(fdc_state[current_fdc].dor, current_fdc, FD_DOR);
+	for (fdc = 0; fdc < N_FDC; fdc++) {
+		if (fdc_state[fdc].address != -1) {
+			reset_fdc_info(fdc, 1);
+			fdc_outb(fdc_state[fdc].dor, fdc, FD_DOR);
 		}
 	}
-	current_fdc = 0;
+
 	set_dor(0, ~0, 8);	/* avoid immediate interrupt */
 
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++)
-		if (fdc_state[current_fdc].address != -1)
-			fdc_outb(fdc_state[current_fdc].dor, current_fdc, FD_DOR);
+	for (fdc = 0; fdc < N_FDC; fdc++)
+		if (fdc_state[fdc].address != -1)
+			fdc_outb(fdc_state[fdc].dor, fdc, FD_DOR);
 	/*
 	 * The driver will try and free resources and relies on us
 	 * to know if they were allocated or not.
@@ -4910,15 +4923,16 @@ static int floppy_grab_irq_and_dma(void)
 cleanup:
 	fd_free_irq();
 	fd_free_dma();
-	while (--current_fdc >= 0)
-		floppy_release_regions(current_fdc);
+	while (--fdc >= 0)
+		floppy_release_regions(fdc);
+	current_fdc = 0;
 	atomic_dec(&usage_count);
 	return -1;
 }
 
 static void floppy_release_irq_and_dma(void)
 {
-	int old_fdc;
+	int fdc;
 #ifndef __sparc__
 	int drive;
 #endif
@@ -4959,11 +4973,9 @@ static void floppy_release_irq_and_dma(void)
 		pr_info("auxiliary floppy timer still active\n");
 	if (work_pending(&floppy_work))
 		pr_info("work still pending\n");
-	old_fdc = current_fdc;
-	for (current_fdc = 0; current_fdc < N_FDC; current_fdc++)
-		if (fdc_state[current_fdc].address != -1)
-			floppy_release_regions(current_fdc);
-	current_fdc = old_fdc;
+	for (fdc = 0; fdc < N_FDC; fdc++)
+		if (fdc_state[fdc].address != -1)
+			floppy_release_regions(fdc);
 }
 
 #ifdef MODULE
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 13dbe2f16882..4212288ab157 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -228,26 +228,36 @@ static void __loop_update_dio(struct loop_device *lo, bool dio)
 		blk_mq_unfreeze_queue(lo->lo_queue);
 }
 
+/**
+ * loop_validate_block_size() - validates the passed in block size
+ * @bsize: size to validate
+ */
 static int
-figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
+loop_validate_block_size(unsigned short bsize)
 {
-	loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
-	sector_t x = (sector_t)size;
-	struct block_device *bdev = lo->lo_device;
+	if (bsize < 512 || bsize > PAGE_SIZE || !is_power_of_2(bsize))
+		return -EINVAL;
 
-	if (unlikely((loff_t)x != size))
-		return -EFBIG;
-	if (lo->lo_offset != offset)
-		lo->lo_offset = offset;
-	if (lo->lo_sizelimit != sizelimit)
-		lo->lo_sizelimit = sizelimit;
-	set_capacity(lo->lo_disk, x);
-	bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9);
-	/* let user-space know about the new size */
-	kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
 	return 0;
 }
 
+/**
+ * loop_set_size() - sets device size and notifies userspace
+ * @lo: struct loop_device to set the size for
+ * @size: new size of the loop device
+ *
+ * Callers must validate that the size passed into this function fits into
+ * a sector_t, eg using loop_validate_size()
+ */
+static void loop_set_size(struct loop_device *lo, loff_t size)
+{
+	struct block_device *bdev = lo->lo_device;
+
+	bd_set_size(bdev, size << SECTOR_SHIFT);
+
+	set_capacity_revalidate_and_notify(lo->lo_disk, size, false);
+}
+
 static inline int
 lo_do_transfer(struct loop_device *lo, int cmd,
 	       struct page *rpage, unsigned roffs,
@@ -952,23 +962,125 @@ static void loop_update_rotational(struct loop_device *lo)
 		blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
 }
 
-static int loop_set_fd(struct loop_device *lo, fmode_t mode,
-		       struct block_device *bdev, unsigned int arg)
+static int
+loop_release_xfer(struct loop_device *lo)
+{
+	int err = 0;
+	struct loop_func_table *xfer = lo->lo_encryption;
+
+	if (xfer) {
+		if (xfer->release)
+			err = xfer->release(lo);
+		lo->transfer = NULL;
+		lo->lo_encryption = NULL;
+		module_put(xfer->owner);
+	}
+	return err;
+}
+
+static int
+loop_init_xfer(struct loop_device *lo, struct loop_func_table *xfer,
+	       const struct loop_info64 *i)
+{
+	int err = 0;
+
+	if (xfer) {
+		struct module *owner = xfer->owner;
+
+		if (!try_module_get(owner))
+			return -EINVAL;
+		if (xfer->init)
+			err = xfer->init(lo, i);
+		if (err)
+			module_put(owner);
+		else
+			lo->lo_encryption = xfer;
+	}
+	return err;
+}
+
+/**
+ * loop_set_status_from_info - configure device from loop_info
+ * @lo: struct loop_device to configure
+ * @info: struct loop_info64 to configure the device with
+ *
+ * Configures the loop device parameters according to the passed
+ * in loop_info64 configuration.
+ */
+static int
+loop_set_status_from_info(struct loop_device *lo,
+			  const struct loop_info64 *info)
+{
+	int err;
+	struct loop_func_table *xfer;
+	kuid_t uid = current_uid();
+
+	if ((unsigned int) info->lo_encrypt_key_size > LO_KEY_SIZE)
+		return -EINVAL;
+
+	err = loop_release_xfer(lo);
+	if (err)
+		return err;
+
+	if (info->lo_encrypt_type) {
+		unsigned int type = info->lo_encrypt_type;
+
+		if (type >= MAX_LO_CRYPT)
+			return -EINVAL;
+		xfer = xfer_funcs[type];
+		if (xfer == NULL)
+			return -EINVAL;
+	} else
+		xfer = NULL;
+
+	err = loop_init_xfer(lo, xfer, info);
+	if (err)
+		return err;
+
+	lo->lo_offset = info->lo_offset;
+	lo->lo_sizelimit = info->lo_sizelimit;
+	memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE);
+	memcpy(lo->lo_crypt_name, info->lo_crypt_name, LO_NAME_SIZE);
+	lo->lo_file_name[LO_NAME_SIZE-1] = 0;
+	lo->lo_crypt_name[LO_NAME_SIZE-1] = 0;
+
+	if (!xfer)
+		xfer = &none_funcs;
+	lo->transfer = xfer->transfer;
+	lo->ioctl = xfer->ioctl;
+
+	lo->lo_flags = info->lo_flags;
+
+	lo->lo_encrypt_key_size = info->lo_encrypt_key_size;
+	lo->lo_init[0] = info->lo_init[0];
+	lo->lo_init[1] = info->lo_init[1];
+	if (info->lo_encrypt_key_size) {
+		memcpy(lo->lo_encrypt_key, info->lo_encrypt_key,
+		       info->lo_encrypt_key_size);
+		lo->lo_key_owner = uid;
+	}
+
+	return 0;
+}
+
+static int loop_configure(struct loop_device *lo, fmode_t mode,
+			  struct block_device *bdev,
+			  const struct loop_config *config)
 {
 	struct file	*file;
 	struct inode	*inode;
 	struct address_space *mapping;
 	struct block_device *claimed_bdev = NULL;
-	int		lo_flags = 0;
 	int		error;
 	loff_t		size;
 	bool		partscan;
+	unsigned short  bsize;
 
 	/* This is safe, since we have a reference from open(). */
 	__module_get(THIS_MODULE);
 
 	error = -EBADF;
-	file = fget(arg);
+	file = fget(config->fd);
 	if (!file)
 		goto out;
 
@@ -977,7 +1089,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
 	 * here to avoid changing device under exclusive owner.
 	 */
 	if (!(mode & FMODE_EXCL)) {
-		claimed_bdev = bd_start_claiming(bdev, loop_set_fd);
+		claimed_bdev = bd_start_claiming(bdev, loop_configure);
 		if (IS_ERR(claimed_bdev)) {
 			error = PTR_ERR(claimed_bdev);
 			goto out_putf;
@@ -999,52 +1111,58 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
 	mapping = file->f_mapping;
 	inode = mapping->host;
 
+	size = get_loop_size(lo, file);
+
+	if ((config->info.lo_flags & ~LOOP_CONFIGURE_SETTABLE_FLAGS) != 0) {
+		error = -EINVAL;
+		goto out_unlock;
+	}
+
+	if (config->block_size) {
+		error = loop_validate_block_size(config->block_size);
+		if (error)
+			goto out_unlock;
+	}
+
+	error = loop_set_status_from_info(lo, &config->info);
+	if (error)
+		goto out_unlock;
+
 	if (!(file->f_mode & FMODE_WRITE) || !(mode & FMODE_WRITE) ||
 	    !file->f_op->write_iter)
-		lo_flags |= LO_FLAGS_READ_ONLY;
+		lo->lo_flags |= LO_FLAGS_READ_ONLY;
 
-	error = -EFBIG;
-	size = get_loop_size(lo, file);
-	if ((loff_t)(sector_t)size != size)
-		goto out_unlock;
 	error = loop_prepare_queue(lo);
 	if (error)
 		goto out_unlock;
 
-	error = 0;
-
-	set_device_ro(bdev, (lo_flags & LO_FLAGS_READ_ONLY) != 0);
+	set_device_ro(bdev, (lo->lo_flags & LO_FLAGS_READ_ONLY) != 0);
 
-	lo->use_dio = false;
+	lo->use_dio = lo->lo_flags & LO_FLAGS_DIRECT_IO;
 	lo->lo_device = bdev;
-	lo->lo_flags = lo_flags;
 	lo->lo_backing_file = file;
-	lo->transfer = NULL;
-	lo->ioctl = NULL;
-	lo->lo_sizelimit = 0;
 	lo->old_gfp_mask = mapping_gfp_mask(mapping);
 	mapping_set_gfp_mask(mapping, lo->old_gfp_mask & ~(__GFP_IO|__GFP_FS));
 
-	if (!(lo_flags & LO_FLAGS_READ_ONLY) && file->f_op->fsync)
+	if (!(lo->lo_flags & LO_FLAGS_READ_ONLY) && file->f_op->fsync)
 		blk_queue_write_cache(lo->lo_queue, true, false);
 
-	if (io_is_direct(lo->lo_backing_file) && inode->i_sb->s_bdev) {
+	if (config->block_size)
+		bsize = config->block_size;
+	else if (io_is_direct(lo->lo_backing_file) && inode->i_sb->s_bdev)
 		/* In case of direct I/O, match underlying block size */
-		unsigned short bsize = bdev_logical_block_size(
-			inode->i_sb->s_bdev);
+		bsize = bdev_logical_block_size(inode->i_sb->s_bdev);
+	else
+		bsize = 512;
 
-		blk_queue_logical_block_size(lo->lo_queue, bsize);
-		blk_queue_physical_block_size(lo->lo_queue, bsize);
-		blk_queue_io_min(lo->lo_queue, bsize);
-	}
+	blk_queue_logical_block_size(lo->lo_queue, bsize);
+	blk_queue_physical_block_size(lo->lo_queue, bsize);
+	blk_queue_io_min(lo->lo_queue, bsize);
 
 	loop_update_rotational(lo);
 	loop_update_dio(lo);
-	set_capacity(lo->lo_disk, size);
-	bd_set_size(bdev, size << 9);
 	loop_sysfs_init(lo);
-	/* let user-space know about the new size */
-	kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
+	loop_set_size(lo, size);
 
 	set_blocksize(bdev, S_ISBLK(inode->i_mode) ?
 		      block_size(inode->i_bdev) : PAGE_SIZE);
@@ -1062,14 +1180,14 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
 	if (partscan)
 		loop_reread_partitions(lo, bdev);
 	if (claimed_bdev)
-		bd_abort_claiming(bdev, claimed_bdev, loop_set_fd);
+		bd_abort_claiming(bdev, claimed_bdev, loop_configure);
 	return 0;
 
 out_unlock:
 	mutex_unlock(&loop_ctl_mutex);
 out_bdev:
 	if (claimed_bdev)
-		bd_abort_claiming(bdev, claimed_bdev, loop_set_fd);
+		bd_abort_claiming(bdev, claimed_bdev, loop_configure);
 out_putf:
 	fput(file);
 out:
@@ -1078,43 +1196,6 @@ out:
 	return error;
 }
 
-static int
-loop_release_xfer(struct loop_device *lo)
-{
-	int err = 0;
-	struct loop_func_table *xfer = lo->lo_encryption;
-
-	if (xfer) {
-		if (xfer->release)
-			err = xfer->release(lo);
-		lo->transfer = NULL;
-		lo->lo_encryption = NULL;
-		module_put(xfer->owner);
-	}
-	return err;
-}
-
-static int
-loop_init_xfer(struct loop_device *lo, struct loop_func_table *xfer,
-	       const struct loop_info64 *i)
-{
-	int err = 0;
-
-	if (xfer) {
-		struct module *owner = xfer->owner;
-
-		if (!try_module_get(owner))
-			return -EINVAL;
-		if (xfer->init)
-			err = xfer->init(lo, i);
-		if (err)
-			module_put(owner);
-		else
-			lo->lo_encryption = xfer;
-	}
-	return err;
-}
-
 static int __loop_clr_fd(struct loop_device *lo, bool release)
 {
 	struct file *filp = NULL;
@@ -1263,10 +1344,11 @@ static int
 loop_set_status(struct loop_device *lo, const struct loop_info64 *info)
 {
 	int err;
-	struct loop_func_table *xfer;
-	kuid_t uid = current_uid();
 	struct block_device *bdev;
+	kuid_t uid = current_uid();
+	int prev_lo_flags;
 	bool partscan = false;
+	bool size_changed = false;
 
 	err = mutex_lock_killable(&loop_ctl_mutex);
 	if (err)
@@ -1281,13 +1363,10 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info)
 		err = -ENXIO;
 		goto out_unlock;
 	}
-	if ((unsigned int) info->lo_encrypt_key_size > LO_KEY_SIZE) {
-		err = -EINVAL;
-		goto out_unlock;
-	}
 
 	if (lo->lo_offset != info->lo_offset ||
 	    lo->lo_sizelimit != info->lo_sizelimit) {
+		size_changed = true;
 		sync_blockdev(lo->lo_device);
 		kill_bdev(lo->lo_device);
 	}
@@ -1295,79 +1374,44 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info)
 	/* I/O need to be drained during transfer transition */
 	blk_mq_freeze_queue(lo->lo_queue);
 
-	err = loop_release_xfer(lo);
-	if (err)
+	if (size_changed && lo->lo_device->bd_inode->i_mapping->nrpages) {
+		/* If any pages were dirtied after kill_bdev(), try again */
+		err = -EAGAIN;
+		pr_warn("%s: loop%d (%s) has still dirty pages (nrpages=%lu)\n",
+			__func__, lo->lo_number, lo->lo_file_name,
+			lo->lo_device->bd_inode->i_mapping->nrpages);
 		goto out_unfreeze;
+	}
 
-	if (info->lo_encrypt_type) {
-		unsigned int type = info->lo_encrypt_type;
-
-		if (type >= MAX_LO_CRYPT) {
-			err = -EINVAL;
-			goto out_unfreeze;
-		}
-		xfer = xfer_funcs[type];
-		if (xfer == NULL) {
-			err = -EINVAL;
-			goto out_unfreeze;
-		}
-	} else
-		xfer = NULL;
+	prev_lo_flags = lo->lo_flags;
 
-	err = loop_init_xfer(lo, xfer, info);
+	err = loop_set_status_from_info(lo, info);
 	if (err)
 		goto out_unfreeze;
 
-	if (lo->lo_offset != info->lo_offset ||
-	    lo->lo_sizelimit != info->lo_sizelimit) {
-		/* kill_bdev should have truncated all the pages */
-		if (lo->lo_device->bd_inode->i_mapping->nrpages) {
-			err = -EAGAIN;
-			pr_warn("%s: loop%d (%s) has still dirty pages (nrpages=%lu)\n",
-				__func__, lo->lo_number, lo->lo_file_name,
-				lo->lo_device->bd_inode->i_mapping->nrpages);
-			goto out_unfreeze;
-		}
-		if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit)) {
-			err = -EFBIG;
-			goto out_unfreeze;
-		}
+	/* Mask out flags that can't be set using LOOP_SET_STATUS. */
+	lo->lo_flags &= ~LOOP_SET_STATUS_SETTABLE_FLAGS;
+	/* For those flags, use the previous values instead */
+	lo->lo_flags |= prev_lo_flags & ~LOOP_SET_STATUS_SETTABLE_FLAGS;
+	/* For flags that can't be cleared, use previous values too */
+	lo->lo_flags |= prev_lo_flags & ~LOOP_SET_STATUS_CLEARABLE_FLAGS;
+
+	if (size_changed) {
+		loff_t new_size = get_size(lo->lo_offset, lo->lo_sizelimit,
+					   lo->lo_backing_file);
+		loop_set_size(lo, new_size);
 	}
 
 	loop_config_discard(lo);
 
-	memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE);
-	memcpy(lo->lo_crypt_name, info->lo_crypt_name, LO_NAME_SIZE);
-	lo->lo_file_name[LO_NAME_SIZE-1] = 0;
-	lo->lo_crypt_name[LO_NAME_SIZE-1] = 0;
-
-	if (!xfer)
-		xfer = &none_funcs;
-	lo->transfer = xfer->transfer;
-	lo->ioctl = xfer->ioctl;
-
-	if ((lo->lo_flags & LO_FLAGS_AUTOCLEAR) !=
-	     (info->lo_flags & LO_FLAGS_AUTOCLEAR))
-		lo->lo_flags ^= LO_FLAGS_AUTOCLEAR;
-
-	lo->lo_encrypt_key_size = info->lo_encrypt_key_size;
-	lo->lo_init[0] = info->lo_init[0];
-	lo->lo_init[1] = info->lo_init[1];
-	if (info->lo_encrypt_key_size) {
-		memcpy(lo->lo_encrypt_key, info->lo_encrypt_key,
-		       info->lo_encrypt_key_size);
-		lo->lo_key_owner = uid;
-	}
-
 	/* update dio if lo_offset or transfer is changed */
 	__loop_update_dio(lo, lo->use_dio);
 
 out_unfreeze:
 	blk_mq_unfreeze_queue(lo->lo_queue);
 
-	if (!err && (info->lo_flags & LO_FLAGS_PARTSCAN) &&
-	     !(lo->lo_flags & LO_FLAGS_PARTSCAN)) {
-		lo->lo_flags |= LO_FLAGS_PARTSCAN;
+	if (!err && (lo->lo_flags & LO_FLAGS_PARTSCAN) &&
+	     !(prev_lo_flags & LO_FLAGS_PARTSCAN)) {
 		lo->lo_disk->flags &= ~GENHD_FL_NO_PART_SCAN;
 		bdev = lo->lo_device;
 		partscan = true;
@@ -1531,10 +1575,15 @@ loop_get_status64(struct loop_device *lo, struct loop_info64 __user *arg) {
 
 static int loop_set_capacity(struct loop_device *lo)
 {
+	loff_t size;
+
 	if (unlikely(lo->lo_state != Lo_bound))
 		return -ENXIO;
 
-	return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit);
+	size = get_loop_size(lo, lo->lo_backing_file);
+	loop_set_size(lo, size);
+
+	return 0;
 }
 
 static int loop_set_dio(struct loop_device *lo, unsigned long arg)
@@ -1558,8 +1607,9 @@ static int loop_set_block_size(struct loop_device *lo, unsigned long arg)
 	if (lo->lo_state != Lo_bound)
 		return -ENXIO;
 
-	if (arg < 512 || arg > PAGE_SIZE || !is_power_of_2(arg))
-		return -EINVAL;
+	err = loop_validate_block_size(arg);
+	if (err)
+		return err;
 
 	if (lo->lo_queue->limits.logical_block_size == arg)
 		return 0;
@@ -1617,11 +1667,31 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode,
 	unsigned int cmd, unsigned long arg)
 {
 	struct loop_device *lo = bdev->bd_disk->private_data;
+	void __user *argp = (void __user *) arg;
 	int err;
 
 	switch (cmd) {
-	case LOOP_SET_FD:
-		return loop_set_fd(lo, mode, bdev, arg);
+	case LOOP_SET_FD: {
+		/*
+		 * Legacy case - pass in a zeroed out struct loop_config with
+		 * only the file descriptor set , which corresponds with the
+		 * default parameters we'd have used otherwise.
+		 */
+		struct loop_config config;
+
+		memset(&config, 0, sizeof(config));
+		config.fd = arg;
+
+		return loop_configure(lo, mode, bdev, &config);
+	}
+	case LOOP_CONFIGURE: {
+		struct loop_config config;
+
+		if (copy_from_user(&config, argp, sizeof(config)))
+			return -EFAULT;
+
+		return loop_configure(lo, mode, bdev, &config);
+	}
 	case LOOP_CHANGE_FD:
 		return loop_change_fd(lo, bdev, arg);
 	case LOOP_CLR_FD:
@@ -1629,21 +1699,19 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode,
 	case LOOP_SET_STATUS:
 		err = -EPERM;
 		if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) {
-			err = loop_set_status_old(lo,
-					(struct loop_info __user *)arg);
+			err = loop_set_status_old(lo, argp);
 		}
 		break;
 	case LOOP_GET_STATUS:
-		return loop_get_status_old(lo, (struct loop_info __user *) arg);
+		return loop_get_status_old(lo, argp);
 	case LOOP_SET_STATUS64:
 		err = -EPERM;
 		if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) {
-			err = loop_set_status64(lo,
-					(struct loop_info64 __user *) arg);
+			err = loop_set_status64(lo, argp);
 		}
 		break;
 	case LOOP_GET_STATUS64:
-		return loop_get_status64(lo, (struct loop_info64 __user *) arg);
+		return loop_get_status64(lo, argp);
 	case LOOP_SET_CAPACITY:
 	case LOOP_SET_DIRECT_IO:
 	case LOOP_SET_BLOCK_SIZE:
@@ -1795,6 +1863,7 @@ static int lo_compat_ioctl(struct block_device *bdev, fmode_t mode,
 	case LOOP_CLR_FD:
 	case LOOP_GET_STATUS64:
 	case LOOP_SET_STATUS64:
+	case LOOP_CONFIGURE:
 		arg = (unsigned long) compat_ptr(arg);
 		/* fall through */
 	case LOOP_SET_FD:
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index 4c297f69171d..dd34504382e5 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -327,7 +327,7 @@ static inline void swim_motor(struct swim __iomem *base,
 			swim_select(base, RELAX);
 			if (swim_readbit(base, MOTOR_ON))
 				break;
-			current->state = TASK_INTERRUPTIBLE;
+			set_current_state(TASK_INTERRUPTIBLE);
 			schedule_timeout(1);
 		}
 	} else if (action == OFF) {
@@ -346,7 +346,7 @@ static inline void swim_eject(struct swim __iomem *base)
 		swim_select(base, RELAX);
 		if (!swim_readbit(base, DISK_IN))
 			break;
-		current->state = TASK_INTERRUPTIBLE;
+		set_current_state(TASK_INTERRUPTIBLE);
 		schedule_timeout(1);
 	}
 	swim_select(base, RELAX);
@@ -370,7 +370,7 @@ static inline int swim_step(struct swim __iomem *base)
 
 	for (wait = 0; wait < HZ; wait++) {
 
-		current->state = TASK_INTERRUPTIBLE;
+		set_current_state(TASK_INTERRUPTIBLE);
 		schedule_timeout(1);
 
 		swim_select(base, RELAX);