: hpilo: fix pointer warning in ilo_ccb_setup [v2]
PATCH 1/1 : hpilo: fix pointer warning in ilo_ccb_setup [v2]
Fix i386 PAE compile warning:
drivers/misc/hpilo.c: In function ‘ilo_ccb_setup’:drivers/misc/hpilo.c:274: warning: cast to pointer from integer of different size
dma_addr_t is 64 on i386 PAE which causes a size mismatch.
drivers/misc/hpilo.c +9 -8
@@ -256,7 +256,8 @@ static void ilo_ccb_close(struct pci_dev *pdev, struct ccb_data *data)static int ilo_ccb_setup (struct ilo_hwinfo *hw,struct ccb_data *data,int slot) { -char *dma_va, *dma_pa; +char *dma_va; +dma_addr_t dma_pa;struct ccb *driver_ccb, *ilo_ccb; driver_ccb = &data->driver_ccb;
@@ -272,12 +273,12 @@ static int ilo_ccb_setup(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)return -ENOMEM ; dma_va = (char *)data->dma_va; - dma_pa = (char *)data->dma_pa; + dma_pa = data->dma_pa;memset (dma_va,0 , data->dma_size); dma_va = (char *)roundup ((unsigned long )dma_va,ILO_START_ALIGN ); - dma_pa = (char *)roundup ((unsigned long )dma_pa,ILO_START_ALIGN ); + dma_pa =roundup (dma_pa,ILO_START_ALIGN );/* * Create two ccb's, one with virt addrs, one with phys addrs.
@@ -288,26 +289,26 @@ static int ilo_ccb_setup(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)fifo_setup (dma_va,NR_QENTRY ); driver_ccb->ccb_u1.send_fifobar = dma_va +FIFOHANDLESIZE ; - ilo_ccb->ccb_u1.send_fifobar = dma_pa +FIFOHANDLESIZE ; + ilo_ccb->ccb_u1.send_fifobar_pa = dma_pa +FIFOHANDLESIZE ; dma_va +=fifo_sz (NR_QENTRY ); dma_pa +=fifo_sz (NR_QENTRY ); dma_va = (char *)roundup ((unsigned long )dma_va,ILO_CACHE_SZ ); - dma_pa = (char *)roundup ((unsigned long )dma_pa,ILO_CACHE_SZ ); + dma_pa =roundup (dma_pa,ILO_CACHE_SZ );fifo_setup (dma_va,NR_QENTRY ); driver_ccb->ccb_u3.recv_fifobar = dma_va +FIFOHANDLESIZE ; - ilo_ccb->ccb_u3.recv_fifobar = dma_pa +FIFOHANDLESIZE ; + ilo_ccb->ccb_u3.recv_fifobar_pa = dma_pa +FIFOHANDLESIZE ; dma_va +=fifo_sz (NR_QENTRY ); dma_pa +=fifo_sz (NR_QENTRY ); driver_ccb->ccb_u2.send_desc = dma_va; - ilo_ccb->ccb_u2.send_desc = dma_pa; + ilo_ccb->ccb_u2.send_desc_pa = dma_pa; dma_pa +=desc_mem_sz (NR_QENTRY ); dma_va +=desc_mem_sz (NR_QENTRY ); driver_ccb->ccb_u4.recv_desc = dma_va; - ilo_ccb->ccb_u4.recv_desc = dma_pa; + ilo_ccb->ccb_u4.recv_desc_pa = dma_pa; driver_ccb->channel = slot; ilo_ccb->channel = slot;
drivers/misc/hpilo.h +4 -4
@@ -79,21 +79,21 @@ struct ilo_hwinfo {struct ccb {union {char *send_fifobar; -u64 padding1; +u64 send_fifobar_pa; } ccb_u1;union {char *send_desc; -u64 padding2; +u64 send_desc_pa; } ccb_u2;u64 send_ctrl;union {char *recv_fifobar; -u64 padding3; +u64 recv_fifobar_pa; } ccb_u3;union {char *recv_desc; -u64 padding4; +u64 recv_desc_pa; } ccb_u4;u64 recv_ctrl;
Quoted 25 lines · On Tue, 8 Jun 2010 11:25:36 -0400 Prarit Bhargava <[email protected]> wrote:
Fix i386 PAE compile warning:
drivers/misc/hpilo.c: In function___ilo_ccb_setup___:drivers/misc/hpilo.c:274: warning: cast to pointer from integer of different size
dma_addr_tis 64 on i386 PAE which causes a size mismatch.Signed-off-by Prarit Bhargava <[email protected]>drivers/misc/hpilo.c +2
-1@@ -256,7 +256,8 @@ static void ilo_ccb_close(struct pci_dev *pdev, struct ccb_data *data)static int ilo_ccb_setup (struct ilo_hwinfo *hw,struct ccb_data *data,int slot) { -char *dma_va, *dma_pa; +char *dma_va; +dma_addr_t dma_pa;struct ccb *driver_ccb, *ilo_ccb; driver_ccb = &data->driver_ccb;@@ -272,12 +273,12 @@ static int ilo_ccb_setup(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)return -ENOMEM ;
drivers/misc/hpilo.c static int ilo_ccb_setup(struct ilo_hwinfo *hw, struct ccb_data *data, int slot) · line 281
Quoted 10 lines
drivers/misc/hpilo.c +2
-2dma_va = (char *)data->dma_va; - dma_pa = (char *)data->dma_pa; + dma_pa = data->dma_pa;memset (dma_va,0 , data->dma_size); dma_va = (char *)roundup ((unsigned long )dma_va,ILO_START_ALIGN ); - dma_pa = (char *)roundup ((unsigned long )dma_pa,ILO_START_ALIGN ); + dma_pa =roundup (dma_pa,ILO_START_ALIGN );
Well. roundup() does division, and 64-bit divides can cause a linkage error on i386. But the compiler will save us because ILO_START_ALIGN is a power-of-2. But as we require that ILO_START_ALIGN be a power-of-2, we may as well use round_up(), which doesn't use division.
Quoted 17 lines
drivers/misc/hpilo.h +2
-2@@ -79,21 +79,21 @@ struct ilo_hwinfo {struct ccb {union {char *send_fifobar; -u64 padding1; +u64 send_fifobar_pa; } ccb_u1;union {char *send_desc; -u64 padding2; +u64 send_desc_pa; } ccb_u2;u64 send_ctrl;union {
drivers/misc/hpilo.h struct ilo_hwinfo { · line 98
Quoted 10 lines
drivers/misc/hpilo.h +2
-2char *recv_fifobar; -u64 padding3; +u64 recv_fifobar_pa; } ccb_u3;union {char *recv_desc; -u64 padding4; +u64 recv_desc_pa; } ccb_u4;u64 recv_ctrl;
So what's happening here. As send_fifobar_pa, send_desc_pa, recv_fifobar_pa and recv_desc_pa are only ever written to, I assume that we're writing a 64-bit value and then reading it back via the 32-bit value which shares the same storage.
Which means that this code doesn't have a hope of working on big-endian machines?
Quoted 5 lines
From Andrew Morton:
So what's happening here. Assend_fifobar_pa,send_desc_pa,recv_fifobar_paandrecv_desc_paare only ever written to, I assume that we're writing a 64-bit value and then reading it back via the 32-bit value which shares the same storage.
The physical addresses are used to fill out a structure defined
by iLO firmware that has 64 bit fields for the various queues or descriptors. A copy with physical addrs is copied to device memory. The size of the structure matters for the physical copy, which is why those fields need to be u64, not a variable type like dma_addr_t, or a pointer.
We keep a copy with virtual addresses for use by the kernel. The size of the kernel pointer doesn't really matter, it just tells the driver where to write in the shared memory. Does that answer your question, maybe I missed what concerned you?