2020-01-08 16:25:53

by Lad, Prabhakar

[permalink] [raw]
Subject: [v3 3/6] PCI: endpoint: Add support to handle multiple base for mapping outbound memory

R-Car PCIe controller has support to map multiple memory regions for
mapping the outbound memory in local system also the controller limits
single allocation for each region (that is, once a chunk is used from the
region it cannot be used to allocate a new one). This features inspires to
add support for handling multiple memory bases in endpoint framework.

With this patch pci_epc_mem_init() now accepts multiple regions, also
page_size for each memory region is passed during initialization so as
to handle single allocation for each region by setting the page_size to
window_size.

Signed-off-by: Lad Prabhakar <[email protected]>
---
.../pci/controller/cadence/pcie-cadence-ep.c | 12 +-
.../pci/controller/dwc/pcie-designware-ep.c | 31 ++-
drivers/pci/controller/pcie-rockchip-ep.c | 14 +-
drivers/pci/endpoint/functions/pci-epf-test.c | 29 +--
drivers/pci/endpoint/pci-epc-core.c | 7 +-
drivers/pci/endpoint/pci-epc-mem.c | 199 ++++++++++++++----
include/linux/pci-epc.h | 46 ++--
7 files changed, 245 insertions(+), 93 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
index 1c173dad67d1..239f27358f1d 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
@@ -143,7 +143,7 @@ static void cdns_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn,
}

static int cdns_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, phys_addr_t addr,
- u64 pci_addr, size_t size)
+ int window, u64 pci_addr, size_t size)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
@@ -401,9 +401,11 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
struct device *dev = ep->pcie.dev;
struct platform_device *pdev = to_platform_device(dev);
struct device_node *np = dev->of_node;
+ struct pci_epc_mem_window mem_window;
struct cdns_pcie *pcie = &ep->pcie;
struct resource *res;
struct pci_epc *epc;
+ int window;
int ret;

pcie->is_rc = false;
@@ -449,15 +451,17 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
if (of_property_read_u8(np, "max-functions", &epc->max_functions) < 0)
epc->max_functions = 1;

- ret = pci_epc_mem_init(epc, pcie->mem_res->start,
- resource_size(pcie->mem_res));
+ mem_window.phys_base = pcie->mem_res->start;
+ mem_window.size = resource_size(pcie->mem_res);
+ mem_window.page_size = PAGE_SIZE;
+ ret = pci_epc_mem_init(epc, &mem_window, 1);
if (ret < 0) {
dev_err(dev, "failed to initialize the memory space\n");
goto err_init;
}

ep->irq_cpu_addr = pci_epc_mem_alloc_addr(epc, &ep->irq_phys_addr,
- SZ_128K);
+ &window, SZ_128K);
if (!ep->irq_cpu_addr) {
dev_err(dev, "failed to reserve memory space for MSI\n");
ret = -ENOMEM;
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 3dd2e2697294..3375874facd3 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -195,7 +195,7 @@ static void dw_pcie_ep_unmap_addr(struct pci_epc *epc, u8 func_no,
}

static int dw_pcie_ep_map_addr(struct pci_epc *epc, u8 func_no,
- phys_addr_t addr,
+ phys_addr_t addr, int window,
u64 pci_addr, size_t size)
{
int ret;
@@ -367,6 +367,7 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
unsigned int aligned_offset;
u16 msg_ctrl, msg_data;
u32 msg_addr_lower, msg_addr_upper, reg;
+ int window = PCI_EPC_DEFAULT_WINDOW;
u64 msg_addr;
bool has_upper;
int ret;
@@ -390,11 +391,11 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
reg = ep->msi_cap + PCI_MSI_DATA_32;
msg_data = dw_pcie_readw_dbi(pci, reg);
}
- aligned_offset = msg_addr_lower & (epc->mem->page_size - 1);
+ aligned_offset = msg_addr_lower & (epc->mem[window]->page_size - 1);
msg_addr = ((u64)msg_addr_upper) << 32 |
(msg_addr_lower & ~aligned_offset);
- ret = dw_pcie_ep_map_addr(epc, func_no, ep->msi_mem_phys, msg_addr,
- epc->mem->page_size);
+ ret = dw_pcie_ep_map_addr(epc, func_no, ep->msi_mem_phys, window,
+ msg_addr, epc->mem[window]->page_size);
if (ret)
return ret;

@@ -416,6 +417,7 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
u32 reg, msg_data, vec_ctrl;
u64 tbl_addr, msg_addr, reg_u64;
void __iomem *msix_tbl;
+ int window = PCI_EPC_DEFAULT_WINDOW;
int ret;

reg = ep->msix_cap + PCI_MSIX_TABLE;
@@ -452,8 +454,8 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
return -EPERM;
}

- ret = dw_pcie_ep_map_addr(epc, func_no, ep->msi_mem_phys, msg_addr,
- epc->mem->page_size);
+ ret = dw_pcie_ep_map_addr(epc, func_no, ep->msi_mem_phys, window,
+ msg_addr, epc->mem[window]->page_size);
if (ret)
return ret;

@@ -466,10 +468,11 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,

void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
{
+ int window = PCI_EPC_DEFAULT_WINDOW;
struct pci_epc *epc = ep->epc;

pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
- epc->mem->page_size);
+ epc->mem[window]->page_size);

pci_epc_mem_exit(epc);
}
@@ -499,9 +502,12 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
u32 reg;
void *addr;
u8 hdr_type;
+ int window;
unsigned int nbars;
unsigned int offset;
struct pci_epc *epc;
+ size_t msi_page_size;
+ struct pci_epc_mem_window mem_window;
struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
struct device *dev = pci->dev;
struct device_node *np = dev->of_node;
@@ -574,15 +580,18 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
if (ret < 0)
epc->max_functions = 1;

- ret = __pci_epc_mem_init(epc, ep->phys_base, ep->addr_size,
- ep->page_size);
+ mem_window.phys_base = ep->phys_base;
+ mem_window.size = ep->addr_size;
+ mem_window.page_size = ep->page_size;
+ ret = __pci_epc_mem_init(epc, &mem_window, 1);
if (ret < 0) {
dev_err(dev, "Failed to initialize address space\n");
return ret;
}

- ep->msi_mem = pci_epc_mem_alloc_addr(epc, &ep->msi_mem_phys,
- epc->mem->page_size);
+ msi_page_size = epc->mem[PCI_EPC_DEFAULT_WINDOW]->page_size;
+ ep->msi_mem = pci_epc_mem_alloc_addr(epc, &ep->msi_mem_phys, &window,
+ msi_page_size);
if (!ep->msi_mem) {
dev_err(dev, "Failed to reserve memory for MSI/MSI-X\n");
return -ENOMEM;
diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c
index d743b0a48988..6c46bed43335 100644
--- a/drivers/pci/controller/pcie-rockchip-ep.c
+++ b/drivers/pci/controller/pcie-rockchip-ep.c
@@ -256,8 +256,8 @@ static void rockchip_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn,
}

static int rockchip_pcie_ep_map_addr(struct pci_epc *epc, u8 fn,
- phys_addr_t addr, u64 pci_addr,
- size_t size)
+ phys_addr_t addr, int window,
+ u64 pci_addr, size_t size)
{
struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
struct rockchip_pcie *pcie = &ep->rockchip;
@@ -562,11 +562,13 @@ static const struct of_device_id rockchip_pcie_ep_of_match[] = {

static int rockchip_pcie_ep_probe(struct platform_device *pdev)
{
+ struct pci_epc_mem_window mem_window;
struct device *dev = &pdev->dev;
struct rockchip_pcie_ep *ep;
struct rockchip_pcie *rockchip;
struct pci_epc *epc;
size_t max_regions;
+ int window;
int err;

ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
@@ -614,15 +616,17 @@ static int rockchip_pcie_ep_probe(struct platform_device *pdev)
/* Only enable function 0 by default */
rockchip_pcie_write(rockchip, BIT(0), PCIE_CORE_PHY_FUNC_CFG);

- err = pci_epc_mem_init(epc, rockchip->mem_res->start,
- resource_size(rockchip->mem_res));
+ mem_window.phys_base = rockchip->mem_res->start;
+ mem_window.size = resource_size(rockchip->mem_res);
+ mem_window.page_size = PAGE_SIZE;
+ err = pci_epc_mem_init(epc, &mem_window, 1);
if (err < 0) {
dev_err(dev, "failed to initialize the memory space\n");
goto err_uninit_port;
}

ep->irq_cpu_addr = pci_epc_mem_alloc_addr(epc, &ep->irq_phys_addr,
- SZ_128K);
+ &window, SZ_128K);
if (!ep->irq_cpu_addr) {
dev_err(dev, "failed to reserve memory space for MSI\n");
err = -ENOMEM;
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 5d74f81ddfe4..475228011703 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -84,8 +84,10 @@ static int pci_epf_test_copy(struct pci_epf_test *epf_test)
struct pci_epc *epc = epf->epc;
enum pci_barno test_reg_bar = epf_test->test_reg_bar;
struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+ int window;

- src_addr = pci_epc_mem_alloc_addr(epc, &src_phys_addr, reg->size);
+ src_addr = pci_epc_mem_alloc_addr(epc, &src_phys_addr,
+ &window, reg->size);
if (!src_addr) {
dev_err(dev, "Failed to allocate source address\n");
reg->status = STATUS_SRC_ADDR_INVALID;
@@ -93,15 +95,16 @@ static int pci_epf_test_copy(struct pci_epf_test *epf_test)
goto err;
}

- ret = pci_epc_map_addr(epc, epf->func_no, src_phys_addr, reg->src_addr,
- reg->size);
+ ret = pci_epc_map_addr(epc, epf->func_no, src_phys_addr, window,
+ reg->src_addr, reg->size);
if (ret) {
dev_err(dev, "Failed to map source address\n");
reg->status = STATUS_SRC_ADDR_INVALID;
goto err_src_addr;
}

- dst_addr = pci_epc_mem_alloc_addr(epc, &dst_phys_addr, reg->size);
+ dst_addr = pci_epc_mem_alloc_addr(epc, &dst_phys_addr,
+ &window, reg->size);
if (!dst_addr) {
dev_err(dev, "Failed to allocate destination address\n");
reg->status = STATUS_DST_ADDR_INVALID;
@@ -109,8 +112,8 @@ static int pci_epf_test_copy(struct pci_epf_test *epf_test)
goto err_src_map_addr;
}

- ret = pci_epc_map_addr(epc, epf->func_no, dst_phys_addr, reg->dst_addr,
- reg->size);
+ ret = pci_epc_map_addr(epc, epf->func_no, dst_phys_addr, window,
+ reg->dst_addr, reg->size);
if (ret) {
dev_err(dev, "Failed to map destination address\n");
reg->status = STATUS_DST_ADDR_INVALID;
@@ -146,8 +149,9 @@ static int pci_epf_test_read(struct pci_epf_test *epf_test)
struct pci_epc *epc = epf->epc;
enum pci_barno test_reg_bar = epf_test->test_reg_bar;
struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+ int window;

- src_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
+ src_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, &window, reg->size);
if (!src_addr) {
dev_err(dev, "Failed to allocate address\n");
reg->status = STATUS_SRC_ADDR_INVALID;
@@ -155,8 +159,8 @@ static int pci_epf_test_read(struct pci_epf_test *epf_test)
goto err;
}

- ret = pci_epc_map_addr(epc, epf->func_no, phys_addr, reg->src_addr,
- reg->size);
+ ret = pci_epc_map_addr(epc, epf->func_no, phys_addr, window,
+ reg->src_addr, reg->size);
if (ret) {
dev_err(dev, "Failed to map address\n");
reg->status = STATUS_SRC_ADDR_INVALID;
@@ -193,13 +197,14 @@ static int pci_epf_test_write(struct pci_epf_test *epf_test)
void __iomem *dst_addr;
void *buf;
phys_addr_t phys_addr;
+ int window;
struct pci_epf *epf = epf_test->epf;
struct device *dev = &epf->dev;
struct pci_epc *epc = epf->epc;
enum pci_barno test_reg_bar = epf_test->test_reg_bar;
struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];

- dst_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
+ dst_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, &window, reg->size);
if (!dst_addr) {
dev_err(dev, "Failed to allocate address\n");
reg->status = STATUS_DST_ADDR_INVALID;
@@ -207,8 +212,8 @@ static int pci_epf_test_write(struct pci_epf_test *epf_test)
goto err;
}

- ret = pci_epc_map_addr(epc, epf->func_no, phys_addr, reg->dst_addr,
- reg->size);
+ ret = pci_epc_map_addr(epc, epf->func_no, phys_addr, window,
+ reg->dst_addr, reg->size);
if (ret) {
dev_err(dev, "Failed to map address\n");
reg->status = STATUS_DST_ADDR_INVALID;
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index 2091508c1620..289c266c2d90 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -358,13 +358,15 @@ EXPORT_SYMBOL_GPL(pci_epc_unmap_addr);
* @epc: the EPC device on which address is allocated
* @func_no: the endpoint function number in the EPC device
* @phys_addr: physical address of the local system
+ * @window: index to the window region where PCI address will be mapped
* @pci_addr: PCI address to which the physical address should be mapped
* @size: the size of the allocation
*
* Invoke to map CPU address with PCI address.
*/
int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
- phys_addr_t phys_addr, u64 pci_addr, size_t size)
+ phys_addr_t phys_addr, int window,
+ u64 pci_addr, size_t size)
{
int ret;
unsigned long flags;
@@ -376,7 +378,8 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
return 0;

spin_lock_irqsave(&epc->lock, flags);
- ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size);
+ ret = epc->ops->map_addr(epc, func_no, phys_addr,
+ window, pci_addr, size);
spin_unlock_irqrestore(&epc->lock, flags);

return ret;
diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
index d2b174ce15de..f205f7819292 100644
--- a/drivers/pci/endpoint/pci-epc-mem.c
+++ b/drivers/pci/endpoint/pci-epc-mem.c
@@ -38,57 +38,77 @@ static int pci_epc_mem_get_order(struct pci_epc_mem *mem, size_t size)
/**
* __pci_epc_mem_init() - initialize the pci_epc_mem structure
* @epc: the EPC device that invoked pci_epc_mem_init
- * @phys_base: the physical address of the base
- * @size: the size of the address space
- * @page_size: size of each page
+ * @windows: pointer to windows supported by the device
+ * @num_windows: number of windows device supports
*
* Invoke to initialize the pci_epc_mem structure used by the
* endpoint functions to allocate mapped PCI address.
*/
-int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size,
- size_t page_size)
+int __pci_epc_mem_init(struct pci_epc *epc, struct pci_epc_mem_window *windows,
+ int num_windows)
{
- int ret;
- struct pci_epc_mem *mem;
- unsigned long *bitmap;
+ struct pci_epc_mem *mem = NULL;
+ unsigned long *bitmap = NULL;
unsigned int page_shift;
- int pages;
+ size_t page_size;
int bitmap_size;
+ int pages;
+ int ret;
+ int i;

- if (page_size < PAGE_SIZE)
- page_size = PAGE_SIZE;
+ epc->mem_windows = 0;

- page_shift = ilog2(page_size);
- pages = size >> page_shift;
- bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
+ if (!windows)
+ return -EINVAL;

- mem = kzalloc(sizeof(*mem), GFP_KERNEL);
- if (!mem) {
- ret = -ENOMEM;
- goto err;
- }
+ if (num_windows <= 0)
+ return -EINVAL;

- bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!bitmap) {
- ret = -ENOMEM;
- goto err_mem;
- }
+ epc->mem = kcalloc(num_windows, sizeof(*mem), GFP_KERNEL);
+ if (!epc->mem)
+ return -EINVAL;
+
+ for (i = 0; i < num_windows; i++) {
+ page_size = windows[i].page_size;
+ if (page_size < PAGE_SIZE)
+ page_size = PAGE_SIZE;
+ page_shift = ilog2(page_size);
+ pages = windows[i].size >> page_shift;
+ bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
+
+ mem = kzalloc(sizeof(*mem), GFP_KERNEL);
+ if (!mem) {
+ ret = -ENOMEM;
+ goto err_mem;
+ }

- mem->bitmap = bitmap;
- mem->phys_base = phys_base;
- mem->page_size = page_size;
- mem->pages = pages;
- mem->size = size;
+ bitmap = kzalloc(bitmap_size, GFP_KERNEL);
+ if (!bitmap) {
+ ret = -ENOMEM;
+ goto err_mem;
+ }

- epc->mem = mem;
+ mem->bitmap = bitmap;
+ mem->window.phys_base = windows[i].phys_base;
+ mem->page_size = page_size;
+ mem->pages = pages;
+ mem->window.size = windows[i].size;
+ mem->window.map_size = 0;
+
+ epc->mem[i] = mem;
+ }
+ epc->mem_windows = num_windows;

return 0;

err_mem:
- kfree(mem);
+ for (; i >= 0; i--) {
+ kfree(mem->bitmap);
+ kfree(epc->mem[i]);
+ }
+ kfree(epc->mem);

-err:
-return ret;
+ return ret;
}
EXPORT_SYMBOL_GPL(__pci_epc_mem_init);

@@ -101,48 +121,127 @@ EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
*/
void pci_epc_mem_exit(struct pci_epc *epc)
{
- struct pci_epc_mem *mem = epc->mem;
+ struct pci_epc_mem *mem;
+ int i;
+
+ if (!epc->mem_windows)
+ return;
+
+ for (i = 0; i <= epc->mem_windows; i++) {
+ mem = epc->mem[i];
+ kfree(mem->bitmap);
+ kfree(epc->mem[i]);
+ }
+ kfree(epc->mem);

epc->mem = NULL;
- kfree(mem->bitmap);
- kfree(mem);
+ epc->mem_windows = 0;
}
EXPORT_SYMBOL_GPL(pci_epc_mem_exit);

+static int pci_epc_find_best_fit_window(struct pci_epc *epc, size_t size)
+{
+ size_t window_least_size = 0;
+ int best_fit_window = -1;
+ struct pci_epc_mem *mem;
+ size_t actual_size;
+ size_t avail_size;
+ int i;
+
+ for (i = 0; i < epc->mem_windows; i++) {
+ mem = epc->mem[i];
+
+ actual_size = ALIGN(size, mem->page_size);
+ avail_size = mem->window.size - mem->window.map_size;
+
+ if (best_fit_window == -1) {
+ if (actual_size <= avail_size) {
+ best_fit_window = i;
+ window_least_size = mem->window.size;
+ }
+ } else {
+ if (actual_size <= avail_size &&
+ mem->window.size < window_least_size) {
+ best_fit_window = i;
+ window_least_size = mem->window.size;
+ }
+ }
+ }
+
+ return best_fit_window;
+}
+
/**
* pci_epc_mem_alloc_addr() - allocate memory address from EPC addr space
* @epc: the EPC device on which memory has to be allocated
* @phys_addr: populate the allocated physical address here
+ * @window: populate the window here which will be used to map PCI address
* @size: the size of the address space that has to be allocated
*
* Invoke to allocate memory address from the EPC address space. This
* is usually done to map the remote RC address into the local system.
*/
void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
- phys_addr_t *phys_addr, size_t size)
+ phys_addr_t *phys_addr,
+ int *window, size_t size)
{
+ int best_fit = PCI_EPC_DEFAULT_WINDOW;
+ void __iomem *virt_addr = NULL;
+ struct pci_epc_mem *mem;
+ unsigned int page_shift;
int pageno;
- void __iomem *virt_addr;
- struct pci_epc_mem *mem = epc->mem;
- unsigned int page_shift = ilog2(mem->page_size);
int order;

+ if (epc->mem_windows <= 0)
+ return NULL;
+
+ if (epc->mem_windows > 1) {
+ best_fit = pci_epc_find_best_fit_window(epc, size);
+ if (best_fit < 0)
+ return NULL;
+ }
+
+ mem = epc->mem[best_fit];
size = ALIGN(size, mem->page_size);
+ if (size > (mem->window.size - mem->window.map_size))
+ return NULL;
+ page_shift = ilog2(mem->page_size);
order = pci_epc_mem_get_order(mem, size);

pageno = bitmap_find_free_region(mem->bitmap, mem->pages, order);
if (pageno < 0)
return NULL;

- *phys_addr = mem->phys_base + ((phys_addr_t)pageno << page_shift);
+ *phys_addr = mem->window.phys_base +
+ ((phys_addr_t)pageno << page_shift);
virt_addr = ioremap(*phys_addr, size);
- if (!virt_addr)
+ if (!virt_addr) {
bitmap_release_region(mem->bitmap, pageno, order);
+ } else {
+ mem->window.map_size += size;
+ *window = best_fit;
+ }

return virt_addr;
}
EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);

+static int pci_epc_get_matching_window(struct pci_epc *epc,
+ phys_addr_t phys_addr)
+{
+ struct pci_epc_mem *mem;
+ int i;
+
+ for (i = 0; i < epc->mem_windows; i++) {
+ mem = epc->mem[i];
+
+ if (mem->window.phys_base == phys_addr)
+ return i;
+ }
+
+ return -EINVAL;
+}
+
/**
* pci_epc_mem_free_addr() - free the allocated memory address
* @epc: the EPC device on which memory was allocated
@@ -155,16 +254,26 @@ EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr,
void __iomem *virt_addr, size_t size)
{
+ struct pci_epc_mem *mem;
+ unsigned int page_shift;
+ int window = 0;
int pageno;
- struct pci_epc_mem *mem = epc->mem;
- unsigned int page_shift = ilog2(mem->page_size);
int order;

+ if (epc->mem_windows > 1) {
+ window = pci_epc_get_matching_window(epc, phys_addr);
+ if (window < 0)
+ return;
+ }
+
+ mem = epc->mem[window];
+ page_shift = ilog2(mem->page_size);
iounmap(virt_addr);
- pageno = (phys_addr - mem->phys_base) >> page_shift;
+ pageno = (phys_addr - mem->window.phys_base) >> page_shift;
size = ALIGN(size, mem->page_size);
order = pci_epc_mem_get_order(mem, size);
bitmap_release_region(mem->bitmap, pageno, order);
+ mem->window.map_size -= size;
}
EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr);

diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index 56f1846b9d39..89daafa0d19f 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -48,7 +48,8 @@ struct pci_epc_ops {
void (*clear_bar)(struct pci_epc *epc, u8 func_no,
struct pci_epf_bar *epf_bar);
int (*map_addr)(struct pci_epc *epc, u8 func_no,
- phys_addr_t addr, u64 pci_addr, size_t size);
+ phys_addr_t addr, int window,
+ u64 pci_addr, size_t size);
void (*unmap_addr)(struct pci_epc *epc, u8 func_no,
phys_addr_t addr);
int (*set_msi)(struct pci_epc *epc, u8 func_no, u8 interrupts);
@@ -64,17 +65,31 @@ struct pci_epc_ops {
struct module *owner;
};

+#define PCI_EPC_DEFAULT_WINDOW 0
+
+/**
+ * struct pci_epc_mem_window - address window of the endpoint controller
+ * @phys_base: physical base address of the PCI address window
+ * @size: the size of the PCI address window
+ * @map_size: size of allocated chunk in window
+ * @page_size: size of each page
+ */
+struct pci_epc_mem_window {
+ phys_addr_t phys_base;
+ size_t size;
+ size_t map_size;
+ size_t page_size;
+};
+
/**
* struct pci_epc_mem - address space of the endpoint controller
- * @phys_base: physical base address of the PCI address space
- * @size: the size of the PCI address space
+ * @window: address window of the endpoint controller
* @bitmap: bitmap to manage the PCI address space
- * @pages: number of bits representing the address region
* @page_size: size of each page
+ * @pages: number of bits representing the address region
*/
struct pci_epc_mem {
- phys_addr_t phys_base;
- size_t size;
+ struct pci_epc_mem_window window;
unsigned long *bitmap;
size_t page_size;
int pages;
@@ -85,7 +100,8 @@ struct pci_epc_mem {
* @dev: PCI EPC device
* @pci_epf: list of endpoint functions present in this EPC device
* @ops: function pointers for performing endpoint operations
- * @mem: address space of the endpoint controller
+ * @mem: array of address space of the endpoint controller
+ * @mem_windows: number of windows supported by device
* @max_functions: max number of functions that can be configured in this EPC
* @group: configfs group representing the PCI EPC device
* @lock: spinlock to protect pci_epc ops
@@ -94,7 +110,8 @@ struct pci_epc {
struct device dev;
struct list_head pci_epf;
const struct pci_epc_ops *ops;
- struct pci_epc_mem *mem;
+ struct pci_epc_mem **mem;
+ int mem_windows;
u8 max_functions;
struct config_group *group;
/* spinlock to protect against concurrent access of EP controller */
@@ -128,8 +145,8 @@ struct pci_epc_features {
#define devm_pci_epc_create(dev, ops) \
__devm_pci_epc_create((dev), (ops), THIS_MODULE)

-#define pci_epc_mem_init(epc, phys_addr, size) \
- __pci_epc_mem_init((epc), (phys_addr), (size), PAGE_SIZE)
+#define pci_epc_mem_init(epc, windows, num_windows) \
+ __pci_epc_mem_init((epc), windows, num_windows)

static inline void epc_set_drvdata(struct pci_epc *epc, void *data)
{
@@ -159,7 +176,7 @@ int pci_epc_set_bar(struct pci_epc *epc, u8 func_no,
void pci_epc_clear_bar(struct pci_epc *epc, u8 func_no,
struct pci_epf_bar *epf_bar);
int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
- phys_addr_t phys_addr,
+ phys_addr_t phys_addr, int window,
u64 pci_addr, size_t size);
void pci_epc_unmap_addr(struct pci_epc *epc, u8 func_no,
phys_addr_t phys_addr);
@@ -178,11 +195,12 @@ unsigned int pci_epc_get_first_free_bar(const struct pci_epc_features
struct pci_epc *pci_epc_get(const char *epc_name);
void pci_epc_put(struct pci_epc *epc);

-int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_addr, size_t size,
- size_t page_size);
+int __pci_epc_mem_init(struct pci_epc *epc, struct pci_epc_mem_window *window,
+ int num_windows);
void pci_epc_mem_exit(struct pci_epc *epc);
void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
- phys_addr_t *phys_addr, size_t size);
+ phys_addr_t *phys_addr,
+ int *window, size_t size);
void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr,
void __iomem *virt_addr, size_t size);
#endif /* __LINUX_PCI_EPC_H */
--
2.20.1


2020-01-09 06:26:53

by Kishon Vijay Abraham I

[permalink] [raw]
Subject: Re: [v3 3/6] PCI: endpoint: Add support to handle multiple base for mapping outbound memory

Hi Prabhakar,

On 08/01/20 9:52 PM, Lad Prabhakar wrote:
> R-Car PCIe controller has support to map multiple memory regions for
> mapping the outbound memory in local system also the controller limits
> single allocation for each region (that is, once a chunk is used from the
> region it cannot be used to allocate a new one). This features inspires to
> add support for handling multiple memory bases in endpoint framework.
>
> With this patch pci_epc_mem_init() now accepts multiple regions, also
> page_size for each memory region is passed during initialization so as
> to handle single allocation for each region by setting the page_size to
> window_size.
>
> Signed-off-by: Lad Prabhakar <[email protected]>
> ---
> .../pci/controller/cadence/pcie-cadence-ep.c | 12 +-
> .../pci/controller/dwc/pcie-designware-ep.c | 31 ++-
> drivers/pci/controller/pcie-rockchip-ep.c | 14 +-
> drivers/pci/endpoint/functions/pci-epf-test.c | 29 +--
> drivers/pci/endpoint/pci-epc-core.c | 7 +-
> drivers/pci/endpoint/pci-epc-mem.c | 199 ++++++++++++++----
> include/linux/pci-epc.h | 46 ++--
> 7 files changed, 245 insertions(+), 93 deletions(-)
>
.
.
<snip>
.
.
> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> index 2091508c1620..289c266c2d90 100644
> --- a/drivers/pci/endpoint/pci-epc-core.c
> +++ b/drivers/pci/endpoint/pci-epc-core.c
> @@ -358,13 +358,15 @@ EXPORT_SYMBOL_GPL(pci_epc_unmap_addr);
> * @epc: the EPC device on which address is allocated
> * @func_no: the endpoint function number in the EPC device
> * @phys_addr: physical address of the local system
> + * @window: index to the window region where PCI address will be mapped
> * @pci_addr: PCI address to which the physical address should be mapped
> * @size: the size of the allocation
> *
> * Invoke to map CPU address with PCI address.
> */
> int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> - phys_addr_t phys_addr, u64 pci_addr, size_t size)
> + phys_addr_t phys_addr, int window,
> + u64 pci_addr, size_t size)
> {
> int ret;
> unsigned long flags;
> @@ -376,7 +378,8 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> return 0;
>
> spin_lock_irqsave(&epc->lock, flags);
> - ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size);
> + ret = epc->ops->map_addr(epc, func_no, phys_addr,
> + window, pci_addr, size);
> spin_unlock_irqrestore(&epc->lock, flags);
>
> return ret;
> diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
> index d2b174ce15de..f205f7819292 100644
> --- a/drivers/pci/endpoint/pci-epc-mem.c
> +++ b/drivers/pci/endpoint/pci-epc-mem.c
> @@ -38,57 +38,77 @@ static int pci_epc_mem_get_order(struct pci_epc_mem *mem, size_t size)
> /**
> * __pci_epc_mem_init() - initialize the pci_epc_mem structure
> * @epc: the EPC device that invoked pci_epc_mem_init
> - * @phys_base: the physical address of the base
> - * @size: the size of the address space
> - * @page_size: size of each page
> + * @windows: pointer to windows supported by the device
> + * @num_windows: number of windows device supports
> *
> * Invoke to initialize the pci_epc_mem structure used by the
> * endpoint functions to allocate mapped PCI address.
> */
> -int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size,
> - size_t page_size)
> +int __pci_epc_mem_init(struct pci_epc *epc, struct pci_epc_mem_window *windows,
> + int num_windows)
> {
> - int ret;
> - struct pci_epc_mem *mem;
> - unsigned long *bitmap;
> + struct pci_epc_mem *mem = NULL;
> + unsigned long *bitmap = NULL;
> unsigned int page_shift;
> - int pages;
> + size_t page_size;
> int bitmap_size;
> + int pages;
> + int ret;
> + int i;
>
> - if (page_size < PAGE_SIZE)
> - page_size = PAGE_SIZE;
> + epc->mem_windows = 0;
>
> - page_shift = ilog2(page_size);
> - pages = size >> page_shift;
> - bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> + if (!windows)
> + return -EINVAL;
>
> - mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> - if (!mem) {
> - ret = -ENOMEM;
> - goto err;
> - }
> + if (num_windows <= 0)
> + return -EINVAL;
>
> - bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> - if (!bitmap) {
> - ret = -ENOMEM;
> - goto err_mem;
> - }
> + epc->mem = kcalloc(num_windows, sizeof(*mem), GFP_KERNEL);
> + if (!epc->mem)
> + return -EINVAL;
> +
> + for (i = 0; i < num_windows; i++) {
> + page_size = windows[i].page_size;
> + if (page_size < PAGE_SIZE)
> + page_size = PAGE_SIZE;
> + page_shift = ilog2(page_size);
> + pages = windows[i].size >> page_shift;
> + bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> +
> + mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> + if (!mem) {
> + ret = -ENOMEM;
> + goto err_mem;
> + }
>
> - mem->bitmap = bitmap;
> - mem->phys_base = phys_base;
> - mem->page_size = page_size;
> - mem->pages = pages;
> - mem->size = size;
> + bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> + if (!bitmap) {
> + ret = -ENOMEM;
> + goto err_mem;
> + }
>
> - epc->mem = mem;
> + mem->bitmap = bitmap;
> + mem->window.phys_base = windows[i].phys_base;
> + mem->page_size = page_size;
> + mem->pages = pages;
> + mem->window.size = windows[i].size;
> + mem->window.map_size = 0;
> +
> + epc->mem[i] = mem;
> + }
> + epc->mem_windows = num_windows;
>
> return 0;
>
> err_mem:
> - kfree(mem);
> + for (; i >= 0; i--) {

mem has to be reinitialized for every iteration of the loop.
> + kfree(mem->bitmap);
> + kfree(epc->mem[i]);
> + }
> + kfree(epc->mem);
>
> -err:
> -return ret;
> + return ret;
> }
> EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
>
> @@ -101,48 +121,127 @@ EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
> */
> void pci_epc_mem_exit(struct pci_epc *epc)
> {
> - struct pci_epc_mem *mem = epc->mem;
> + struct pci_epc_mem *mem;
> + int i;
> +
> + if (!epc->mem_windows)
> + return;
> +
> + for (i = 0; i <= epc->mem_windows; i++) {
> + mem = epc->mem[i];
> + kfree(mem->bitmap);
> + kfree(epc->mem[i]);
> + }
> + kfree(epc->mem);
>
> epc->mem = NULL;
> - kfree(mem->bitmap);
> - kfree(mem);
> + epc->mem_windows = 0;
> }
> EXPORT_SYMBOL_GPL(pci_epc_mem_exit);
>
> +static int pci_epc_find_best_fit_window(struct pci_epc *epc, size_t size)
> +{
> + size_t window_least_size = 0;
> + int best_fit_window = -1;
> + struct pci_epc_mem *mem;
> + size_t actual_size;
> + size_t avail_size;
> + int i;
> +
> + for (i = 0; i < epc->mem_windows; i++) {
> + mem = epc->mem[i];
> +
> + actual_size = ALIGN(size, mem->page_size);
> + avail_size = mem->window.size - mem->window.map_size;
> +
> + if (best_fit_window == -1) {
> + if (actual_size <= avail_size) {
> + best_fit_window = i;
> + window_least_size = mem->window.size;
> + }
> + } else {
> + if (actual_size <= avail_size &&
> + mem->window.size < window_least_size) {
> + best_fit_window = i;
> + window_least_size = mem->window.size;
> + }
> + }
> + }
> +
> + return best_fit_window;
> +}

This function shouldn't be required at all. Just loop over all the
windows invoking bitmap_find_free_region(), breaking the loop if it
succeeds and continuing if there is no free region.
> +
> /**
> * pci_epc_mem_alloc_addr() - allocate memory address from EPC addr space
> * @epc: the EPC device on which memory has to be allocated
> * @phys_addr: populate the allocated physical address here
> + * @window: populate the window here which will be used to map PCI address
> * @size: the size of the address space that has to be allocated
> *
> * Invoke to allocate memory address from the EPC address space. This
> * is usually done to map the remote RC address into the local system.
> */
> void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
> - phys_addr_t *phys_addr, size_t size)
> + phys_addr_t *phys_addr,
> + int *window, size_t size)
> {
> + int best_fit = PCI_EPC_DEFAULT_WINDOW;
> + void __iomem *virt_addr = NULL;
> + struct pci_epc_mem *mem;
> + unsigned int page_shift;
> int pageno;
> - void __iomem *virt_addr;
> - struct pci_epc_mem *mem = epc->mem;
> - unsigned int page_shift = ilog2(mem->page_size);
> int order;
>
> + if (epc->mem_windows <= 0)
> + return NULL;
> +
> + if (epc->mem_windows > 1) {
> + best_fit = pci_epc_find_best_fit_window(epc, size);
> + if (best_fit < 0)
> + return NULL;
> + }
> +
> + mem = epc->mem[best_fit];
> size = ALIGN(size, mem->page_size);
> + if (size > (mem->window.size - mem->window.map_size))
> + return NULL;
> + page_shift = ilog2(mem->page_size);
> order = pci_epc_mem_get_order(mem, size);
>
> pageno = bitmap_find_free_region(mem->bitmap, mem->pages, order);
> if (pageno < 0)
> return NULL;

This has to be invoked now in a loop for the number of windows. If
pageno < 0, continue the loop or else break.
>
> - *phys_addr = mem->phys_base + ((phys_addr_t)pageno << page_shift);
> + *phys_addr = mem->window.phys_base +
> + ((phys_addr_t)pageno << page_shift);
> virt_addr = ioremap(*phys_addr, size);
> - if (!virt_addr)
> + if (!virt_addr) {
> bitmap_release_region(mem->bitmap, pageno, order);
> + } else {
> + mem->window.map_size += size;

The map_size shouldn't be required.
> + *window = best_fit;

Can't the platform driver get the window based on the address? Let's try
to avoid modifying API's for platform specific requirements.
> + }
>
> return virt_addr;
> }
> EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
>
> +static int pci_epc_get_matching_window(struct pci_epc *epc,
> + phys_addr_t phys_addr)
> +{
> + struct pci_epc_mem *mem;
> + int i;
> +
> + for (i = 0; i < epc->mem_windows; i++) {
> + mem = epc->mem[i];
> +
> + if (mem->window.phys_base == phys_addr)
> + return i;
> + }
> +
> + return -EINVAL;
> +}
> +
> /**
> * pci_epc_mem_free_addr() - free the allocated memory address
> * @epc: the EPC device on which memory was allocated
> @@ -155,16 +254,26 @@ EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
> void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr,
> void __iomem *virt_addr, size_t size)
> {
> + struct pci_epc_mem *mem;
> + unsigned int page_shift;
> + int window = 0;
> int pageno;
> - struct pci_epc_mem *mem = epc->mem;
> - unsigned int page_shift = ilog2(mem->page_size);
> int order;
>
> + if (epc->mem_windows > 1) {
> + window = pci_epc_get_matching_window(epc, phys_addr);
> + if (window < 0)
> + return;
> + }
> +
> + mem = epc->mem[window];
> + page_shift = ilog2(mem->page_size);
> iounmap(virt_addr);
> - pageno = (phys_addr - mem->phys_base) >> page_shift;
> + pageno = (phys_addr - mem->window.phys_base) >> page_shift;
> size = ALIGN(size, mem->page_size);
> order = pci_epc_mem_get_order(mem, size);
> bitmap_release_region(mem->bitmap, pageno, order);
> + mem->window.map_size -= size;
> }
> EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr);
>
> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
> index 56f1846b9d39..89daafa0d19f 100644
> --- a/include/linux/pci-epc.h
> +++ b/include/linux/pci-epc.h
> @@ -48,7 +48,8 @@ struct pci_epc_ops {
> void (*clear_bar)(struct pci_epc *epc, u8 func_no,
> struct pci_epf_bar *epf_bar);
> int (*map_addr)(struct pci_epc *epc, u8 func_no,
> - phys_addr_t addr, u64 pci_addr, size_t size);
> + phys_addr_t addr, int window,
> + u64 pci_addr, size_t size);
> void (*unmap_addr)(struct pci_epc *epc, u8 func_no,
> phys_addr_t addr);
> int (*set_msi)(struct pci_epc *epc, u8 func_no, u8 interrupts);
> @@ -64,17 +65,31 @@ struct pci_epc_ops {
> struct module *owner;
> };
>
> +#define PCI_EPC_DEFAULT_WINDOW 0
> +
> +/**
> + * struct pci_epc_mem_window - address window of the endpoint controller
> + * @phys_base: physical base address of the PCI address window
> + * @size: the size of the PCI address window
> + * @map_size: size of allocated chunk in window
> + * @page_size: size of each page
> + */
> +struct pci_epc_mem_window {
> + phys_addr_t phys_base;
> + size_t size;
> + size_t map_size;

mem->bitmap already holds the map_size information. This structure can
be used only for passing info about the mem windows from platform to the
core. So map_size shouldn't be required.

Thanks
Kishon

2020-01-10 18:11:18

by Lad, Prabhakar

[permalink] [raw]
Subject: Re: [v3 3/6] PCI: endpoint: Add support to handle multiple base for mapping outbound memory

Hi Kishon,

Thank you for the review.

On Thu, Jan 9, 2020 at 6:25 AM Kishon Vijay Abraham I <[email protected]> wrote:
>
> Hi Prabhakar,
>
> On 08/01/20 9:52 PM, Lad Prabhakar wrote:
> > R-Car PCIe controller has support to map multiple memory regions for
> > mapping the outbound memory in local system also the controller limits
> > single allocation for each region (that is, once a chunk is used from the
> > region it cannot be used to allocate a new one). This features inspires to
> > add support for handling multiple memory bases in endpoint framework.
> >
> > With this patch pci_epc_mem_init() now accepts multiple regions, also
> > page_size for each memory region is passed during initialization so as
> > to handle single allocation for each region by setting the page_size to
> > window_size.
> >
> > Signed-off-by: Lad Prabhakar <[email protected]>
> > ---
> > .../pci/controller/cadence/pcie-cadence-ep.c | 12 +-
> > .../pci/controller/dwc/pcie-designware-ep.c | 31 ++-
> > drivers/pci/controller/pcie-rockchip-ep.c | 14 +-
> > drivers/pci/endpoint/functions/pci-epf-test.c | 29 +--
> > drivers/pci/endpoint/pci-epc-core.c | 7 +-
> > drivers/pci/endpoint/pci-epc-mem.c | 199 ++++++++++++++----
> > include/linux/pci-epc.h | 46 ++--
> > 7 files changed, 245 insertions(+), 93 deletions(-)
> >
> .
> .
> <snip>
> .
> .
> > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> > index 2091508c1620..289c266c2d90 100644
> > --- a/drivers/pci/endpoint/pci-epc-core.c
> > +++ b/drivers/pci/endpoint/pci-epc-core.c
> > @@ -358,13 +358,15 @@ EXPORT_SYMBOL_GPL(pci_epc_unmap_addr);
> > * @epc: the EPC device on which address is allocated
> > * @func_no: the endpoint function number in the EPC device
> > * @phys_addr: physical address of the local system
> > + * @window: index to the window region where PCI address will be mapped
> > * @pci_addr: PCI address to which the physical address should be mapped
> > * @size: the size of the allocation
> > *
> > * Invoke to map CPU address with PCI address.
> > */
> > int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> > - phys_addr_t phys_addr, u64 pci_addr, size_t size)
> > + phys_addr_t phys_addr, int window,
> > + u64 pci_addr, size_t size)
> > {
> > int ret;
> > unsigned long flags;
> > @@ -376,7 +378,8 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> > return 0;
> >
> > spin_lock_irqsave(&epc->lock, flags);
> > - ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size);
> > + ret = epc->ops->map_addr(epc, func_no, phys_addr,
> > + window, pci_addr, size);
> > spin_unlock_irqrestore(&epc->lock, flags);
> >
> > return ret;
> > diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
> > index d2b174ce15de..f205f7819292 100644
> > --- a/drivers/pci/endpoint/pci-epc-mem.c
> > +++ b/drivers/pci/endpoint/pci-epc-mem.c
> > @@ -38,57 +38,77 @@ static int pci_epc_mem_get_order(struct pci_epc_mem *mem, size_t size)
> > /**
> > * __pci_epc_mem_init() - initialize the pci_epc_mem structure
> > * @epc: the EPC device that invoked pci_epc_mem_init
> > - * @phys_base: the physical address of the base
> > - * @size: the size of the address space
> > - * @page_size: size of each page
> > + * @windows: pointer to windows supported by the device
> > + * @num_windows: number of windows device supports
> > *
> > * Invoke to initialize the pci_epc_mem structure used by the
> > * endpoint functions to allocate mapped PCI address.
> > */
> > -int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size,
> > - size_t page_size)
> > +int __pci_epc_mem_init(struct pci_epc *epc, struct pci_epc_mem_window *windows,
> > + int num_windows)
> > {
> > - int ret;
> > - struct pci_epc_mem *mem;
> > - unsigned long *bitmap;
> > + struct pci_epc_mem *mem = NULL;
> > + unsigned long *bitmap = NULL;
> > unsigned int page_shift;
> > - int pages;
> > + size_t page_size;
> > int bitmap_size;
> > + int pages;
> > + int ret;
> > + int i;
> >
> > - if (page_size < PAGE_SIZE)
> > - page_size = PAGE_SIZE;
> > + epc->mem_windows = 0;
> >
> > - page_shift = ilog2(page_size);
> > - pages = size >> page_shift;
> > - bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> > + if (!windows)
> > + return -EINVAL;
> >
> > - mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> > - if (!mem) {
> > - ret = -ENOMEM;
> > - goto err;
> > - }
> > + if (num_windows <= 0)
> > + return -EINVAL;
> >
> > - bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> > - if (!bitmap) {
> > - ret = -ENOMEM;
> > - goto err_mem;
> > - }
> > + epc->mem = kcalloc(num_windows, sizeof(*mem), GFP_KERNEL);
> > + if (!epc->mem)
> > + return -EINVAL;
> > +
> > + for (i = 0; i < num_windows; i++) {
> > + page_size = windows[i].page_size;
> > + if (page_size < PAGE_SIZE)
> > + page_size = PAGE_SIZE;
> > + page_shift = ilog2(page_size);
> > + pages = windows[i].size >> page_shift;
> > + bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> > +
> > + mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> > + if (!mem) {
> > + ret = -ENOMEM;
> > + goto err_mem;
> > + }
> >
> > - mem->bitmap = bitmap;
> > - mem->phys_base = phys_base;
> > - mem->page_size = page_size;
> > - mem->pages = pages;
> > - mem->size = size;
> > + bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> > + if (!bitmap) {
> > + ret = -ENOMEM;
> > + goto err_mem;
> > + }
> >
> > - epc->mem = mem;
> > + mem->bitmap = bitmap;
> > + mem->window.phys_base = windows[i].phys_base;
> > + mem->page_size = page_size;
> > + mem->pages = pages;
> > + mem->window.size = windows[i].size;
> > + mem->window.map_size = 0;
> > +
> > + epc->mem[i] = mem;
> > + }
> > + epc->mem_windows = num_windows;
> >
> > return 0;
> >
> > err_mem:
> > - kfree(mem);
> > + for (; i >= 0; i--) {
>
> mem has to be reinitialized for every iteration of the loop.
not sure what exactly you mean here, could you please elaborate.

> > + kfree(mem->bitmap);
> > + kfree(epc->mem[i]);
> > + }
> > + kfree(epc->mem);
> >
> > -err:
> > -return ret;
> > + return ret;
> > }
> > EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
> >
> > @@ -101,48 +121,127 @@ EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
> > */
> > void pci_epc_mem_exit(struct pci_epc *epc)
> > {
> > - struct pci_epc_mem *mem = epc->mem;
> > + struct pci_epc_mem *mem;
> > + int i;
> > +
> > + if (!epc->mem_windows)
> > + return;
> > +
> > + for (i = 0; i <= epc->mem_windows; i++) {
> > + mem = epc->mem[i];
> > + kfree(mem->bitmap);
> > + kfree(epc->mem[i]);
> > + }
> > + kfree(epc->mem);
> >
> > epc->mem = NULL;
> > - kfree(mem->bitmap);
> > - kfree(mem);
> > + epc->mem_windows = 0;
> > }
> > EXPORT_SYMBOL_GPL(pci_epc_mem_exit);
> >
> > +static int pci_epc_find_best_fit_window(struct pci_epc *epc, size_t size)
> > +{
> > + size_t window_least_size = 0;
> > + int best_fit_window = -1;
> > + struct pci_epc_mem *mem;
> > + size_t actual_size;
> > + size_t avail_size;
> > + int i;
> > +
> > + for (i = 0; i < epc->mem_windows; i++) {
> > + mem = epc->mem[i];
> > +
> > + actual_size = ALIGN(size, mem->page_size);
> > + avail_size = mem->window.size - mem->window.map_size;
> > +
> > + if (best_fit_window == -1) {
> > + if (actual_size <= avail_size) {
> > + best_fit_window = i;
> > + window_least_size = mem->window.size;
> > + }
> > + } else {
> > + if (actual_size <= avail_size &&
> > + mem->window.size < window_least_size) {
> > + best_fit_window = i;
> > + window_least_size = mem->window.size;
> > + }
> > + }
> > + }
> > +
> > + return best_fit_window;
> > +}
>
> This function shouldn't be required at all. Just loop over all the
> windows invoking bitmap_find_free_region(), breaking the loop if it
> succeeds and continuing if there is no free region.
sure will do.
> > +
> > /**
> > * pci_epc_mem_alloc_addr() - allocate memory address from EPC addr space
> > * @epc: the EPC device on which memory has to be allocated
> > * @phys_addr: populate the allocated physical address here
> > + * @window: populate the window here which will be used to map PCI address
> > * @size: the size of the address space that has to be allocated
> > *
> > * Invoke to allocate memory address from the EPC address space. This
> > * is usually done to map the remote RC address into the local system.
> > */
> > void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
> > - phys_addr_t *phys_addr, size_t size)
> > + phys_addr_t *phys_addr,
> > + int *window, size_t size)
> > {
> > + int best_fit = PCI_EPC_DEFAULT_WINDOW;
> > + void __iomem *virt_addr = NULL;
> > + struct pci_epc_mem *mem;
> > + unsigned int page_shift;
> > int pageno;
> > - void __iomem *virt_addr;
> > - struct pci_epc_mem *mem = epc->mem;
> > - unsigned int page_shift = ilog2(mem->page_size);
> > int order;
> >
> > + if (epc->mem_windows <= 0)
> > + return NULL;
> > +
> > + if (epc->mem_windows > 1) {
> > + best_fit = pci_epc_find_best_fit_window(epc, size);
> > + if (best_fit < 0)
> > + return NULL;
> > + }
> > +
> > + mem = epc->mem[best_fit];
> > size = ALIGN(size, mem->page_size);
> > + if (size > (mem->window.size - mem->window.map_size))
> > + return NULL;
> > + page_shift = ilog2(mem->page_size);
> > order = pci_epc_mem_get_order(mem, size);
> >
> > pageno = bitmap_find_free_region(mem->bitmap, mem->pages, order);
> > if (pageno < 0)
> > return NULL;
>
> This has to be invoked now in a loop for the number of windows. If
> pageno < 0, continue the loop or else break.
> >
will fix that.

> > - *phys_addr = mem->phys_base + ((phys_addr_t)pageno << page_shift);
> > + *phys_addr = mem->window.phys_base +
> > + ((phys_addr_t)pageno << page_shift);
> > virt_addr = ioremap(*phys_addr, size);
> > - if (!virt_addr)
> > + if (!virt_addr) {
> > bitmap_release_region(mem->bitmap, pageno, order);
> > + } else {
> > + mem->window.map_size += size;
>
> The map_size shouldn't be required.
> > + *window = best_fit;
>
> Can't the platform driver get the window based on the address? Let's try
> to avoid modifying API's for platform specific requirements.
should be possible, will do that.

> > + }
> >
> > return virt_addr;
> > }
> > EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
> >
> > +static int pci_epc_get_matching_window(struct pci_epc *epc,
> > + phys_addr_t phys_addr)
> > +{
> > + struct pci_epc_mem *mem;
> > + int i;
> > +
> > + for (i = 0; i < epc->mem_windows; i++) {
> > + mem = epc->mem[i];
> > +
> > + if (mem->window.phys_base == phys_addr)
> > + return i;
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > /**
> > * pci_epc_mem_free_addr() - free the allocated memory address
> > * @epc: the EPC device on which memory was allocated
> > @@ -155,16 +254,26 @@ EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr);
> > void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr,
> > void __iomem *virt_addr, size_t size)
> > {
> > + struct pci_epc_mem *mem;
> > + unsigned int page_shift;
> > + int window = 0;
> > int pageno;
> > - struct pci_epc_mem *mem = epc->mem;
> > - unsigned int page_shift = ilog2(mem->page_size);
> > int order;
> >
> > + if (epc->mem_windows > 1) {
> > + window = pci_epc_get_matching_window(epc, phys_addr);
> > + if (window < 0)
> > + return;
> > + }
> > +
> > + mem = epc->mem[window];
> > + page_shift = ilog2(mem->page_size);
> > iounmap(virt_addr);
> > - pageno = (phys_addr - mem->phys_base) >> page_shift;
> > + pageno = (phys_addr - mem->window.phys_base) >> page_shift;
> > size = ALIGN(size, mem->page_size);
> > order = pci_epc_mem_get_order(mem, size);
> > bitmap_release_region(mem->bitmap, pageno, order);
> > + mem->window.map_size -= size;
> > }
> > EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr);
> >
> > diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
> > index 56f1846b9d39..89daafa0d19f 100644
> > --- a/include/linux/pci-epc.h
> > +++ b/include/linux/pci-epc.h
> > @@ -48,7 +48,8 @@ struct pci_epc_ops {
> > void (*clear_bar)(struct pci_epc *epc, u8 func_no,
> > struct pci_epf_bar *epf_bar);
> > int (*map_addr)(struct pci_epc *epc, u8 func_no,
> > - phys_addr_t addr, u64 pci_addr, size_t size);
> > + phys_addr_t addr, int window,
> > + u64 pci_addr, size_t size);
> > void (*unmap_addr)(struct pci_epc *epc, u8 func_no,
> > phys_addr_t addr);
> > int (*set_msi)(struct pci_epc *epc, u8 func_no, u8 interrupts);
> > @@ -64,17 +65,31 @@ struct pci_epc_ops {
> > struct module *owner;
> > };
> >
> > +#define PCI_EPC_DEFAULT_WINDOW 0
> > +
> > +/**
> > + * struct pci_epc_mem_window - address window of the endpoint controller
> > + * @phys_base: physical base address of the PCI address window
> > + * @size: the size of the PCI address window
> > + * @map_size: size of allocated chunk in window
> > + * @page_size: size of each page
> > + */
> > +struct pci_epc_mem_window {
> > + phys_addr_t phys_base;
> > + size_t size;
> > + size_t map_size;
>
> mem->bitmap already holds the map_size information. This structure can
> be used only for passing info about the mem windows from platform to the
> core. So map_size shouldn't be required.
>
agreed will drop it.

Cheers,
--Prabhakar

2020-01-13 08:58:21

by Kishon Vijay Abraham I

[permalink] [raw]
Subject: Re: [v3 3/6] PCI: endpoint: Add support to handle multiple base for mapping outbound memory

Hi Prabhakar,

On 10/01/20 11:38 PM, Lad, Prabhakar wrote:
> Hi Kishon,
>
> Thank you for the review.
>
> On Thu, Jan 9, 2020 at 6:25 AM Kishon Vijay Abraham I <[email protected]> wrote:
>>
>> Hi Prabhakar,
>>
>> On 08/01/20 9:52 PM, Lad Prabhakar wrote:
>>> R-Car PCIe controller has support to map multiple memory regions for
>>> mapping the outbound memory in local system also the controller limits
>>> single allocation for each region (that is, once a chunk is used from the
>>> region it cannot be used to allocate a new one). This features inspires to
>>> add support for handling multiple memory bases in endpoint framework.
>>>
>>> With this patch pci_epc_mem_init() now accepts multiple regions, also
>>> page_size for each memory region is passed during initialization so as
>>> to handle single allocation for each region by setting the page_size to
>>> window_size.
>>>
>>> Signed-off-by: Lad Prabhakar <[email protected]>
>>> ---
>>> .../pci/controller/cadence/pcie-cadence-ep.c | 12 +-
>>> .../pci/controller/dwc/pcie-designware-ep.c | 31 ++-
>>> drivers/pci/controller/pcie-rockchip-ep.c | 14 +-
>>> drivers/pci/endpoint/functions/pci-epf-test.c | 29 +--
>>> drivers/pci/endpoint/pci-epc-core.c | 7 +-
>>> drivers/pci/endpoint/pci-epc-mem.c | 199 ++++++++++++++----
>>> include/linux/pci-epc.h | 46 ++--
>>> 7 files changed, 245 insertions(+), 93 deletions(-)
>>>
>> .
>> .
>> <snip>
>> .
>> .
>>> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
>>> index 2091508c1620..289c266c2d90 100644
>>> --- a/drivers/pci/endpoint/pci-epc-core.c
>>> +++ b/drivers/pci/endpoint/pci-epc-core.c
>>> @@ -358,13 +358,15 @@ EXPORT_SYMBOL_GPL(pci_epc_unmap_addr);
>>> * @epc: the EPC device on which address is allocated
>>> * @func_no: the endpoint function number in the EPC device
>>> * @phys_addr: physical address of the local system
>>> + * @window: index to the window region where PCI address will be mapped
>>> * @pci_addr: PCI address to which the physical address should be mapped
>>> * @size: the size of the allocation
>>> *
>>> * Invoke to map CPU address with PCI address.
>>> */
>>> int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
>>> - phys_addr_t phys_addr, u64 pci_addr, size_t size)
>>> + phys_addr_t phys_addr, int window,
>>> + u64 pci_addr, size_t size)
>>> {
>>> int ret;
>>> unsigned long flags;
>>> @@ -376,7 +378,8 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
>>> return 0;
>>>
>>> spin_lock_irqsave(&epc->lock, flags);
>>> - ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size);
>>> + ret = epc->ops->map_addr(epc, func_no, phys_addr,
>>> + window, pci_addr, size);
>>> spin_unlock_irqrestore(&epc->lock, flags);
>>>
>>> return ret;
>>> diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
>>> index d2b174ce15de..f205f7819292 100644
>>> --- a/drivers/pci/endpoint/pci-epc-mem.c
>>> +++ b/drivers/pci/endpoint/pci-epc-mem.c
>>> @@ -38,57 +38,77 @@ static int pci_epc_mem_get_order(struct pci_epc_mem *mem, size_t size)
>>> /**
>>> * __pci_epc_mem_init() - initialize the pci_epc_mem structure
>>> * @epc: the EPC device that invoked pci_epc_mem_init
>>> - * @phys_base: the physical address of the base
>>> - * @size: the size of the address space
>>> - * @page_size: size of each page
>>> + * @windows: pointer to windows supported by the device
>>> + * @num_windows: number of windows device supports
>>> *
>>> * Invoke to initialize the pci_epc_mem structure used by the
>>> * endpoint functions to allocate mapped PCI address.
>>> */
>>> -int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size,
>>> - size_t page_size)
>>> +int __pci_epc_mem_init(struct pci_epc *epc, struct pci_epc_mem_window *windows,
>>> + int num_windows)
>>> {
>>> - int ret;
>>> - struct pci_epc_mem *mem;
>>> - unsigned long *bitmap;
>>> + struct pci_epc_mem *mem = NULL;
>>> + unsigned long *bitmap = NULL;
>>> unsigned int page_shift;
>>> - int pages;
>>> + size_t page_size;
>>> int bitmap_size;
>>> + int pages;
>>> + int ret;
>>> + int i;
>>>
>>> - if (page_size < PAGE_SIZE)
>>> - page_size = PAGE_SIZE;
>>> + epc->mem_windows = 0;
>>>
>>> - page_shift = ilog2(page_size);
>>> - pages = size >> page_shift;
>>> - bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
>>> + if (!windows)
>>> + return -EINVAL;
>>>
>>> - mem = kzalloc(sizeof(*mem), GFP_KERNEL);
>>> - if (!mem) {
>>> - ret = -ENOMEM;
>>> - goto err;
>>> - }
>>> + if (num_windows <= 0)
>>> + return -EINVAL;
>>>
>>> - bitmap = kzalloc(bitmap_size, GFP_KERNEL);
>>> - if (!bitmap) {
>>> - ret = -ENOMEM;
>>> - goto err_mem;
>>> - }
>>> + epc->mem = kcalloc(num_windows, sizeof(*mem), GFP_KERNEL);
>>> + if (!epc->mem)
>>> + return -EINVAL;
>>> +
>>> + for (i = 0; i < num_windows; i++) {
>>> + page_size = windows[i].page_size;
>>> + if (page_size < PAGE_SIZE)
>>> + page_size = PAGE_SIZE;
>>> + page_shift = ilog2(page_size);
>>> + pages = windows[i].size >> page_shift;
>>> + bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
>>> +
>>> + mem = kzalloc(sizeof(*mem), GFP_KERNEL);
>>> + if (!mem) {
>>> + ret = -ENOMEM;
>>> + goto err_mem;
>>> + }
>>>
>>> - mem->bitmap = bitmap;
>>> - mem->phys_base = phys_base;
>>> - mem->page_size = page_size;
>>> - mem->pages = pages;
>>> - mem->size = size;
>>> + bitmap = kzalloc(bitmap_size, GFP_KERNEL);
>>> + if (!bitmap) {
>>> + ret = -ENOMEM;
>>> + goto err_mem;
>>> + }
>>>
>>> - epc->mem = mem;
>>> + mem->bitmap = bitmap;
>>> + mem->window.phys_base = windows[i].phys_base;
>>> + mem->page_size = page_size;
>>> + mem->pages = pages;
>>> + mem->window.size = windows[i].size;
>>> + mem->window.map_size = 0;
>>> +
>>> + epc->mem[i] = mem;
>>> + }
>>> + epc->mem_windows = num_windows;
>>>
>>> return 0;
>>>
>>> err_mem:
>>> - kfree(mem);
>>> + for (; i >= 0; i--) {
>>
>> mem has to be reinitialized for every iteration of the loop.
> not sure what exactly you mean here, could you please elaborate.

You are invoking "kfree(mem->bitmap);" in a loop without re-initializing
mem. Refer pci_epc_mem_exit() where you are doing the free properly.

>
>>> + kfree(mem->bitmap);
>>> + kfree(epc->mem[i]);
>>> + }
>>> + kfree(epc->mem);
>>>
>>> -err:
>>> -return ret;
>>> + return ret;
>>> }
>>> EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
>>>
>>> @@ -101,48 +121,127 @@ EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
>>> */
>>> void pci_epc_mem_exit(struct pci_epc *epc)
>>> {
>>> - struct pci_epc_mem *mem = epc->mem;
>>> + struct pci_epc_mem *mem;
>>> + int i;
>>> +
>>> + if (!epc->mem_windows)
>>> + return;
>>> +
>>> + for (i = 0; i <= epc->mem_windows; i++) {
>>> + mem = epc->mem[i];

Missing the above line in the error handling above.


>>> + kfree(mem->bitmap);
>>> + kfree(epc->mem[i]);
>>> + }

Thanks
Kishon

2020-01-14 08:12:22

by Lad, Prabhakar

[permalink] [raw]
Subject: Re: [v3 3/6] PCI: endpoint: Add support to handle multiple base for mapping outbound memory

Hi Kishon,

On Mon, Jan 13, 2020 at 8:56 AM Kishon Vijay Abraham I <[email protected]> wrote:
>
> Hi Prabhakar,
>
> On 10/01/20 11:38 PM, Lad, Prabhakar wrote:
> > Hi Kishon,
> >
> > Thank you for the review.
> >
> > On Thu, Jan 9, 2020 at 6:25 AM Kishon Vijay Abraham I <[email protected]> wrote:
> >>
> >> Hi Prabhakar,
> >>
> >> On 08/01/20 9:52 PM, Lad Prabhakar wrote:
> >>> R-Car PCIe controller has support to map multiple memory regions for
> >>> mapping the outbound memory in local system also the controller limits
> >>> single allocation for each region (that is, once a chunk is used from the
> >>> region it cannot be used to allocate a new one). This features inspires to
> >>> add support for handling multiple memory bases in endpoint framework.
> >>>
> >>> With this patch pci_epc_mem_init() now accepts multiple regions, also
> >>> page_size for each memory region is passed during initialization so as
> >>> to handle single allocation for each region by setting the page_size to
> >>> window_size.
> >>>
> >>> Signed-off-by: Lad Prabhakar <[email protected]>
> >>> ---
> >>> .../pci/controller/cadence/pcie-cadence-ep.c | 12 +-
> >>> .../pci/controller/dwc/pcie-designware-ep.c | 31 ++-
> >>> drivers/pci/controller/pcie-rockchip-ep.c | 14 +-
> >>> drivers/pci/endpoint/functions/pci-epf-test.c | 29 +--
> >>> drivers/pci/endpoint/pci-epc-core.c | 7 +-
> >>> drivers/pci/endpoint/pci-epc-mem.c | 199 ++++++++++++++----
> >>> include/linux/pci-epc.h | 46 ++--
> >>> 7 files changed, 245 insertions(+), 93 deletions(-)
> >>>
> >> .
> >> .
> >> <snip>
> >> .
> >> .
> >>> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> >>> index 2091508c1620..289c266c2d90 100644
> >>> --- a/drivers/pci/endpoint/pci-epc-core.c
> >>> +++ b/drivers/pci/endpoint/pci-epc-core.c
> >>> @@ -358,13 +358,15 @@ EXPORT_SYMBOL_GPL(pci_epc_unmap_addr);
> >>> * @epc: the EPC device on which address is allocated
> >>> * @func_no: the endpoint function number in the EPC device
> >>> * @phys_addr: physical address of the local system
> >>> + * @window: index to the window region where PCI address will be mapped
> >>> * @pci_addr: PCI address to which the physical address should be mapped
> >>> * @size: the size of the allocation
> >>> *
> >>> * Invoke to map CPU address with PCI address.
> >>> */
> >>> int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> >>> - phys_addr_t phys_addr, u64 pci_addr, size_t size)
> >>> + phys_addr_t phys_addr, int window,
> >>> + u64 pci_addr, size_t size)
> >>> {
> >>> int ret;
> >>> unsigned long flags;
> >>> @@ -376,7 +378,8 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no,
> >>> return 0;
> >>>
> >>> spin_lock_irqsave(&epc->lock, flags);
> >>> - ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size);
> >>> + ret = epc->ops->map_addr(epc, func_no, phys_addr,
> >>> + window, pci_addr, size);
> >>> spin_unlock_irqrestore(&epc->lock, flags);
> >>>
> >>> return ret;
> >>> diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
> >>> index d2b174ce15de..f205f7819292 100644
> >>> --- a/drivers/pci/endpoint/pci-epc-mem.c
> >>> +++ b/drivers/pci/endpoint/pci-epc-mem.c
> >>> @@ -38,57 +38,77 @@ static int pci_epc_mem_get_order(struct pci_epc_mem *mem, size_t size)
> >>> /**
> >>> * __pci_epc_mem_init() - initialize the pci_epc_mem structure
> >>> * @epc: the EPC device that invoked pci_epc_mem_init
> >>> - * @phys_base: the physical address of the base
> >>> - * @size: the size of the address space
> >>> - * @page_size: size of each page
> >>> + * @windows: pointer to windows supported by the device
> >>> + * @num_windows: number of windows device supports
> >>> *
> >>> * Invoke to initialize the pci_epc_mem structure used by the
> >>> * endpoint functions to allocate mapped PCI address.
> >>> */
> >>> -int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size,
> >>> - size_t page_size)
> >>> +int __pci_epc_mem_init(struct pci_epc *epc, struct pci_epc_mem_window *windows,
> >>> + int num_windows)
> >>> {
> >>> - int ret;
> >>> - struct pci_epc_mem *mem;
> >>> - unsigned long *bitmap;
> >>> + struct pci_epc_mem *mem = NULL;
> >>> + unsigned long *bitmap = NULL;
> >>> unsigned int page_shift;
> >>> - int pages;
> >>> + size_t page_size;
> >>> int bitmap_size;
> >>> + int pages;
> >>> + int ret;
> >>> + int i;
> >>>
> >>> - if (page_size < PAGE_SIZE)
> >>> - page_size = PAGE_SIZE;
> >>> + epc->mem_windows = 0;
> >>>
> >>> - page_shift = ilog2(page_size);
> >>> - pages = size >> page_shift;
> >>> - bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> >>> + if (!windows)
> >>> + return -EINVAL;
> >>>
> >>> - mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> >>> - if (!mem) {
> >>> - ret = -ENOMEM;
> >>> - goto err;
> >>> - }
> >>> + if (num_windows <= 0)
> >>> + return -EINVAL;
> >>>
> >>> - bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> >>> - if (!bitmap) {
> >>> - ret = -ENOMEM;
> >>> - goto err_mem;
> >>> - }
> >>> + epc->mem = kcalloc(num_windows, sizeof(*mem), GFP_KERNEL);
> >>> + if (!epc->mem)
> >>> + return -EINVAL;
> >>> +
> >>> + for (i = 0; i < num_windows; i++) {
> >>> + page_size = windows[i].page_size;
> >>> + if (page_size < PAGE_SIZE)
> >>> + page_size = PAGE_SIZE;
> >>> + page_shift = ilog2(page_size);
> >>> + pages = windows[i].size >> page_shift;
> >>> + bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
> >>> +
> >>> + mem = kzalloc(sizeof(*mem), GFP_KERNEL);
> >>> + if (!mem) {
> >>> + ret = -ENOMEM;
> >>> + goto err_mem;
> >>> + }
> >>>
> >>> - mem->bitmap = bitmap;
> >>> - mem->phys_base = phys_base;
> >>> - mem->page_size = page_size;
> >>> - mem->pages = pages;
> >>> - mem->size = size;
> >>> + bitmap = kzalloc(bitmap_size, GFP_KERNEL);
> >>> + if (!bitmap) {
> >>> + ret = -ENOMEM;
> >>> + goto err_mem;
> >>> + }
> >>>
> >>> - epc->mem = mem;
> >>> + mem->bitmap = bitmap;
> >>> + mem->window.phys_base = windows[i].phys_base;
> >>> + mem->page_size = page_size;
> >>> + mem->pages = pages;
> >>> + mem->window.size = windows[i].size;
> >>> + mem->window.map_size = 0;
> >>> +
> >>> + epc->mem[i] = mem;
> >>> + }
> >>> + epc->mem_windows = num_windows;
> >>>
> >>> return 0;
> >>>
> >>> err_mem:
> >>> - kfree(mem);
> >>> + for (; i >= 0; i--) {
> >>
> >> mem has to be reinitialized for every iteration of the loop.
> > not sure what exactly you mean here, could you please elaborate.
>
> You are invoking "kfree(mem->bitmap);" in a loop without re-initializing
> mem. Refer pci_epc_mem_exit() where you are doing the free properly.
>
good catch will fix that.

Cheers,
--Prabhakar

> >
> >>> + kfree(mem->bitmap);
> >>> + kfree(epc->mem[i]);
> >>> + }
> >>> + kfree(epc->mem);
> >>>
> >>> -err:
> >>> -return ret;
> >>> + return ret;
> >>> }
> >>> EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
> >>>
> >>> @@ -101,48 +121,127 @@ EXPORT_SYMBOL_GPL(__pci_epc_mem_init);
> >>> */
> >>> void pci_epc_mem_exit(struct pci_epc *epc)
> >>> {
> >>> - struct pci_epc_mem *mem = epc->mem;
> >>> + struct pci_epc_mem *mem;
> >>> + int i;
> >>> +
> >>> + if (!epc->mem_windows)
> >>> + return;
> >>> +
> >>> + for (i = 0; i <= epc->mem_windows; i++) {
> >>> + mem = epc->mem[i];
>
> Missing the above line in the error handling above.
>
>
> >>> + kfree(mem->bitmap);
> >>> + kfree(epc->mem[i]);
> >>> + }
>
> Thanks
> Kishon